1.
Standing wave
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In physics, a standing wave – also known as a stationary wave – is a wave in a medium in which each point on the axis of the wave has an associated constant amplitude. The locations at which the amplitude is minimum are called nodes, standing waves were first noticed by Michael Faraday in 1831. Faraday observed standing waves on the surface of a liquid in a vibrating container, franz Melde coined the term standing wave around 1860 and demonstrated the phenomenon in his classic experiment with vibrating strings. For waves of equal amplitude traveling in opposing directions, there is on average no net propagation of energy, as an example of the first type, under certain meteorological conditions standing waves form in the atmosphere in the lee of mountain ranges. Such waves are often exploited by glider pilots, standing waves and hydraulic jumps also form on fast flowing river rapids and tidal currents such as the Saltstraumen maelstrom. Many standing river waves are popular river surfing breaks, the effect is a series of nodes and anti-nodes at fixed points along the transmission line. The failure of the line to power at the standing wave frequency will usually result in attenuation distortion. In practice, losses in the line and other components mean that a perfect reflection. The result is a standing wave, which is a superposition of a standing wave. The degree to which the wave resembles either a standing wave or a pure traveling wave is measured by the standing wave ratio. Another example is standing waves in the ocean formed by waves with the same wave period moving in opposite directions. These may form near storm centres, or from reflection of a swell at the shore, in one dimension, two waves with the same frequency, wavelength and amplitude traveling in opposite directions will interfere and produce a standing wave or stationary wave. The reflected wave has to have the amplitude and frequency as the incoming wave. At locations which are multiples of a quarter wavelength x =. −3 λ2, − λ, − λ2,0, λ2, λ,3 λ2, called the nodes, the amplitude is always zero, whereas at locations which are odd multiples of a quarter wavelength x =. −5 λ4, −3 λ4, − λ4, λ4,3 λ4,5 λ4, called the anti-nodes, the amplitude is maximum, with a value of twice the amplitude of the original waves. The distance between two nodes or anti-nodes is λ/2. Standing waves can occur in two- or three-dimensional resonators
2.
Reservoir
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A reservoir is a storage space for fluids. These fluids may be water, hydrocarbons or gas, a reservoir usually means an enlarged natural or artificial lake, storage pond or impoundment created using a dam or lock to store water. Reservoirs can be created by controlling a stream that drains a body of water. They can also be constructed in river valleys using a dam, alternately, a reservoir can be built by excavating flat ground or constructing retaining walls and levees. Tank reservoirs store liquids or gases in storage tanks that may be elevated, at grade level, tank reservoirs for water are also called cisterns. Underground reservoirs are used to store liquids, principally either water or petroleum, a dam constructed in a valley relies on the natural topography to provide most of the basin of the reservoir. Dams are typically located at a part of a valley downstream of a natural basin. The valley sides act as walls, with the dam located at the narrowest practical point to provide strength. In many reservoir construction projects, people have to be moved and re-housed, construction of a reservoir in a valley will usually need the river to be diverted during part of the build, often through a temporary tunnel or by-pass channel. In hilly regions, reservoirs are constructed by enlarging existing lakes. Sometimes in such reservoirs the new top water level exceeds the height on one or more of the feeder streams such as at Llyn Clywedog in Mid Wales. In such cases additional side dams are required to contain the reservoir, where water is pumped or siphoned from a river of variable quality or quantity, bank-side reservoirs may be built to store the water. Such reservoirs are usually formed partly by excavation and partly by building a complete encircling bund or embankment, the water stored in such reservoirs may stay there for several months, during which time normal biological processes may substantially reduce many contaminants and almost eliminate any turbidity. The use of reservoirs also allows water abstraction to be stopped for some time. Service reservoirs store fully treated potable water close to the point of distribution, many service reservoirs are constructed as water towers, often as elevated structures on concrete pillars where the landscape is relatively flat. Other service reservoirs can be almost entirely underground, especially in hilly or mountainous country. In the United Kingdom, Thames Water has many underground reservoirs, sometimes called cisterns, built in the 1800s. A good example is the Honor Oak Reservoir in London, constructed between 1901 and 1909, when it was completed it was said to be the largest brick built underground reservoir in the world and it is still one of the largest in Europe
3.
Hydrology
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Hydrology is the scientific study of the movement, distribution, and quality of water on Earth and other planets, including the water cycle, water resources and environmental watershed sustainability. A practitioner of hydrology is a hydrologist, working within the fields of earth or environmental science, physical geography, geology or civil, Hydrology subdivides into surface water hydrology, groundwater hydrology, and marine hydrology. Domains of hydrology include hydrometeorology, surface hydrology, hydrogeology, drainage-basin management and water quality, oceanography and meteorology are not included because water is only one of many important aspects within those fields. Hydrological research can inform environmental engineering, policy and planning, the term hydrology comes from Greek, ὕδωρ, hýdōr, water, and λόγος, lógos, study. Chemical hydrology is the study of the characteristics of water. Ecohydrology is the study of interactions between organisms and the hydrologic cycle, hydrogeology is the study of the presence and movement of groundwater. Hydroinformatics is the adaptation of technology to hydrology and water resources applications. Hydrometeorology is the study of the transfer of water and energy between land and water surfaces and the lower atmosphere. Isotope hydrology is the study of the signatures of water. Surface hydrology is the study of processes that operate at or near Earths surface. Drainage basin management covers water-storage, in the form of reservoirs, water quality includes the chemistry of water in rivers and lakes, both of pollutants and natural solutes. Determining the water balance of a region, mitigating and predicting flood, landslide and drought risk. Real-time flood forecasting and flood warning, designing irrigation schemes and managing agricultural productivity. Part of the module in catastrophe modeling. Designing dams for water supply or hydroelectric power generation, designing sewers and urban drainage system. Analyzing the impacts of antecedent moisture on sanitary sewer systems, predicting geomorphologic changes, such as erosion or sedimentation. Assessing the impacts of natural and anthropogenic environmental change on water resources, assessing contaminant transport risk and establishing environmental policy guidelines. Hydrology has been a subject of investigation and engineering for millennia, for example, about 4000 BC the Nile was dammed to improve agricultural productivity of previously barren lands
4.
Lake Geneva
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Lake Geneva is a lake on the north side of the Alps, shared between Switzerland and France. It is one of the largest lakes in Western Europe and the largest on the course of the Rhône,59. 53% of it comes under the jurisdiction of Switzerland, and 40. 47% under France. Lake Geneva has been explored by four submarines, the Auguste Piccard, forel, both built by Jacques Piccard, and the two Mir submersibles. Following the rise of Geneva it became Lac de Genève, in the 18th century, Lac Léman was revived in French and is the customary name in that language. In contemporary English, the name Lake Geneva is predominant, a note on pronunciation, English, Lake Geneva /ˌleɪk dʒᵻˈniːvə/ French, le lac Léman, le Léman or le lac de Genève German, Genfersee or Genfer See Italian, Lago Lemano, Lago di Ginevra. The Chablais Alps border is its southern shore, the western Bernese Alps lie over its eastern side, the high summits of Grand Combin and Mont Blanc are visible from some places. Compagnie Générale de Navigation sur le lac Léman operates boats on the lake, the lake lies on the course of the Rhône. Other tributaries are La Dranse, LAubonne, La Morges, La Venoge, La Vuachère, Lake Geneva is the largest body of water in Switzerland, and greatly exceeds in size all others that are connected with the main valleys of the Alps. It is in the shape of a crescent, with the horns pointing south, the northern shore being 95 km, the crescent form was more regular in a recent geological period, when the lake extended to Bex, about 18 km south of Villeneuve. The lakes surface is the lowest point of the cantons of Valais, the culminating point of the lakes drainage basin is Monte Rosa at 4,634 metres above sea level. The beauty of the shores of the lake and of the sites of many of the places near its banks has long been celebrated, however, it is only from the eastern end of the lake, between Vevey and Villeneuve, that the scenery assumes an Alpine character. The shore between Nyon and Lausanne is called La Côte because it is flatter, between Lausanne and Vevey it is called Lavaux and is famous for its hilly vineyards. The average surface elevation of 372 m above sea level is controlled by the Seujet Dam in Geneva, simulations indicate that the Tauredunum event was most likely caused by a massive landslide near the Rhône delta, which caused a wave eight meters high to reach Geneva within 70 minutes. In 888 the town was part of the new Kingdom of Burgundy, in the late 1960s, pollution made it dangerous to swim at some beaches of the lake, indeed, visibility under water was near zero. By the 1980s, intense environmental pollution had almost wiped out all the fish, today, pollution levels have been dramatically cut back, and it is again considered safe to swim in the lake. Major leisure activities practiced include sailing, wind surfing, boating, rowing, on a scientific footnote, in 1827, Lake Geneva was the site for the first measurement of the speed of sound in water. The loud airborne sound coupled into the lake, establishing an underwater sound that could be measured at a distance. The flash of the exploding gunpowder provided the starting cue for the timepiece
5.
Switzerland
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Switzerland, officially the Swiss Confederation, is a federal republic in Europe. It consists of 26 cantons, and the city of Bern is the seat of the federal authorities. The country is situated in western-Central Europe, and is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland is a country geographically divided between the Alps, the Swiss Plateau and the Jura, spanning an area of 41,285 km2. The establishment of the Old Swiss Confederacy dates to the medieval period, resulting from a series of military successes against Austria. Swiss independence from the Holy Roman Empire was formally recognized in the Peace of Westphalia in 1648. The country has a history of armed neutrality going back to the Reformation, it has not been in a state of war internationally since 1815, nevertheless, it pursues an active foreign policy and is frequently involved in peace-building processes around the world. In addition to being the birthplace of the Red Cross, Switzerland is home to international organisations. On the European level, it is a member of the European Free Trade Association. However, it participates in the Schengen Area and the European Single Market through bilateral treaties, spanning the intersection of Germanic and Romance Europe, Switzerland comprises four main linguistic and cultural regions, German, French, Italian and Romansh. Due to its diversity, Switzerland is known by a variety of native names, Schweiz, Suisse, Svizzera. On coins and stamps, Latin is used instead of the four living languages, Switzerland is one of the most developed countries in the world, with the highest nominal wealth per adult and the eighth-highest per capita gross domestic product according to the IMF. Zürich and Geneva have each been ranked among the top cities in the world in terms of quality of life, with the former ranked second globally, according to Mercer. The English name Switzerland is a compound containing Switzer, a term for the Swiss. The English adjective Swiss is a loan from French Suisse, also in use since the 16th century. The name Switzer is from the Alemannic Schwiizer, in origin an inhabitant of Schwyz and its associated territory, the Swiss began to adopt the name for themselves after the Swabian War of 1499, used alongside the term for Confederates, Eidgenossen, used since the 14th century. The data code for Switzerland, CH, is derived from Latin Confoederatio Helvetica. The toponym Schwyz itself was first attested in 972, as Old High German Suittes, ultimately related to swedan ‘to burn’
6.
Swiss French
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Swiss French is the variety of French spoken in the French-speaking area of Switzerland known as Romandy. French is one of the four languages of Switzerland, the others being German, Italian. As of 2012, around 1.8 million people in the country spoke French as their primary language, the French language spoken in Switzerland differs very little from that of France or Belgium, with minor and mostly lexical differences. While Standard French is taught in schools and used in government, media and this is exemplified by the usage of borrowed terms from German in regions bordering German-speaking communities to their complete absence by the French border area around Geneva. Many differences between Swiss French and French are due to the different administrative and political systems between Switzerland and France, in France, a post office box is called a boite postale, whereas in Switzerland, it is called a case postale. Swiss German Swiss Italian Linguistic geography of Switzerland
7.
Infragravity wave
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Infragravity waves are ocean surface gravity waves generated by ocean waves of shorter periods. The amplitude of infragravity waves is most relevant in shallow water, in particular along coastlines hit by high amplitude and long period wind waves, wind waves and ocean swells are shorter, with typical dominant periods of 1 to 25 s. This distinguishes infragravity waves from normal oceanic gravity waves, which are created by wind acting on the surface of the sea, whatever the details of their generation mechanism, discussed below, infragravity waves are these subharmonics of the impinging gravity waves. Technically infragravity waves are simply a subcategory of gravity waves and refer to all gravity waves with greater than 30 s. This could include such as tides and oceanic Rossby waves. The term infragravity wave appears to have coined by Walter Munk in 1950. Two main processes can explain the transfer of energy from the wind waves to the long infragravity waves. The most common process is the interaction of trains of wind waves which was first observed by Munk and Tucker and explained by Longuet-Higgins. Because wind waves are not monochromatic they form groups, the Stokes drift induced by these groupy waves transports more water where the waves are highest. The waves also push the water around in a way that can be interpreted as a force, combining mass and momentum conservation, Longuet-Higgins and Stewart give, with three different methods, the now well-known result. Namely, the sea level oscillates with a wavelength that is equal to the length of the group, with a low level where the wind waves are highest. This oscillation of the sea surface is proportional to the square of the wave amplitude. Another process was proposed later by Graham Symonds and his collaborators and it appears that this is probably a good explanation for infragravity wave generation on a reef. In the case of coral reefs, the infragravity periods are established by resonances with the reef itself, infragravity waves generated along the Pacific coast of North America have been observed to propagate transoceanically to Antarctica and there to impinge on the Ross Ice Shelf. Their frequencies more closely couple with the ice shelf natural frequencies, further, they are not damped by sea ice as normal ocean swell is. As a result, they flex floating ice shelves such as the Ross Ice Shelf, media related to Gravity waves at Wikimedia Commons
8.
Undertone series
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In music, the undertone series or subharmonic series is a sequence of notes that results from inverting the intervals of the overtone series. While overtones naturally occur with the production of music on instruments. The overtone series being a series, the undertone series is based on arithmetic division. The hybrid term subharmonic is used in music and dynamics in a few different ways, in its pure sense, the term subharmonic refers strictly to any member of the subharmonic series. When the subharmonic series is used to refer to frequency relationships, the complex tones of acoustic instruments do not produce partials that resemble the subharmonic series. However, such tones can be produced artificially with audio software, subharmonics can be contrasted with harmonics. While harmonics can. occur in any system, there are. only fairly restricted conditions that will lead to the nonlinear phenomenon known as subharmonic generation. One way to define subharmonics is that they are. integral submultiples of the fundamental frequency, the human voice can also be forced into a similar driven resonance, also called “undertone singing”, to extend the range of the voice below what is normally available. The overtone series can be produced physically in two ways—either by overblowing a wind instrument, or by dividing a monochord string. If a monochord string is lightly damped at the point, then at 1/3, then 1/4, 1/5, etc. then the string will produce the overtone series. If instead, the length of the string is doubled in the opposite ratios, similarly, on a wind instrument, if the holes are equally spaced, each successive hole covered will produce the next note in the undertone series. In addition, José Sotorrio showed that undertones could be made through the use of an oscillator such as a tuning fork. If that oscillator is gently forced to vibrate against a sheet of paper it will make contact at various audible modes of vibration. The tritare, a guitar with Y shaped strings, cause subharmonics too and this can also be achieved by the extended technique of crossing two strings as some experimental jazz guitarists have developed. Also third bridge preparations on guitars cause timbres consisting of sets of high pitched overtones combined with a resonant tone of the unplugged part of the string. Subharmonics can be produced by signal amplification through loudspeakers, Subharmonic frequencies are frequencies below the fundamental frequency of an oscillator in a ratio of 1/n, with n a positive integer number. For example, if the frequency of an oscillator is 440 Hz, sub-harmonics include 220 Hz. Thus, they are an image of the harmonic series
9.
Nonlinear system
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In mathematics and physical sciences, a nonlinear system is a system in which the change of the output is not proportional to the change of the input. Nonlinear problems are of interest to engineers, physicists and mathematicians, nonlinear systems may appear chaotic, unpredictable or counterintuitive, contrasting with the much simpler linear systems. In other words, in a system of equations, the equation to be solved cannot be written as a linear combination of the unknown variables or functions that appear in them. Systems can be defined as non-linear, regardless of whether or not known linear functions appear in the equations. In particular, an equation is linear if it is linear in terms of the unknown function and its derivatives. As nonlinear equations are difficult to solve, nonlinear systems are approximated by linear equations. This works well up to some accuracy and some range for the input values and it follows that some aspects of the behavior of a nonlinear system appear commonly to be counterintuitive, unpredictable or even chaotic. Although such chaotic behavior may resemble random behavior, it is not random. For example, some aspects of the weather are seen to be chaotic and this nonlinearity is one of the reasons why accurate long-term forecasts are impossible with current technology. Some authors use the term nonlinear science for the study of nonlinear systems and this is disputed by others, Using a term like nonlinear science is like referring to the bulk of zoology as the study of non-elephant animals. In mathematics, a function f is one which satisfies both of the following properties, Additivity or superposition, f = f + f, Homogeneity. Additivity implies homogeneity for any rational α, and, for continuous functions, for a complex α, homogeneity does not follow from additivity. For example, a map is additive but not homogeneous. The equation is called homogeneous if C =0, if f contains differentiation with respect to x, the result will be a differential equation. Nonlinear algebraic equations, which are also called polynomial equations, are defined by equating polynomials to zero, for example, x 2 + x −1 =0. For a single equation, root-finding algorithms can be used to find solutions to the equation. However, systems of equations are more complicated, their study is one motivation for the field of algebraic geometry. It is even difficult to decide whether a given system has complex solutions
10.
Wind wave
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In fluid dynamics, wind waves, or wind-generated waves, are surface waves that occur on the free surface of bodies of water. They result from the wind blowing over an area of fluid surface, Waves in the oceans can travel thousands of miles before reaching land. Wind waves on Earth range in size from small ripples, to waves over 100 ft high, when directly generated and affected by local winds, a wind wave system is called a wind sea. After the wind ceases to blow, wind waves are called swells, more generally, a swell consists of wind-generated waves that are not significantly affected by the local wind at that time. They have been generated elsewhere or some time ago, wind waves in the ocean are called ocean surface waves. Wind waves have an amount of randomness, subsequent waves differ in height, duration. The key statistics of wind waves in evolving sea states can be predicted with wind wave models, although waves are usually considered in the water seas of Earth, the hydrocarbon seas of Titan may also have wind-driven waves. The great majority of large breakers seen at a result from distant winds. Water depth All of these work together to determine the size of wind waves. Further exposure to that wind could only cause a dissipation of energy due to the breaking of wave tops. Waves in an area typically have a range of heights. For weather reporting and for analysis of wind wave statistics. This figure represents an average height of the highest one-third of the waves in a time period. The significant wave height is also the value a trained observer would estimate from visual observation of a sea state, given the variability of wave height, the largest individual waves are likely to be somewhat less than twice the reported significant wave height for a particular day or storm. Wave formation on a flat water surface by wind is started by a random distribution of normal pressure of turbulent wind flow over the water. This pressure fluctuation produces normal and tangential stresses in the surface water and it is assumed that, The water is originally at rest. There is a distribution of normal pressure to the water surface from the turbulent wind. Correlations between air and water motions are neglected, the second mechanism involves wind shear forces on the water surface
11.
Tsunami
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A tsunami or tidal wave, also known as a seismic sea wave, is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Unlike normal ocean waves which are generated by wind, or tides which are generated by the pull of the Moon and Sun. Tsunami waves do not resemble normal undersea currents or sea waves, Tsunamis generally consist of a series of waves with periods ranging from minutes to hours, arriving in a so-called internal wave train. Wave heights of tens of metres can be generated by large events, numerous terms are used in the English language to describe waves created in a body of water by the displacement of water, however, none of the terms in frequent use are entirely accurate. The term tsunami, meaning harbour wave in literal translation, comes from the Japanese 津波, while not entirely accurate, as tsunami are not restricted to harbours, tsunami is currently the term most widely accepted by geologists and oceanographers. Tsunami are sometimes referred to as tidal waves and this once-popular term derives from the most common appearance of tsunami, which is that of an extraordinarily high tidal bore. Although the meanings of tidal include resembling or having the form or character of the tides, use of the tidal wave is discouraged by geologists. The term seismic sea wave also is used to refer to the phenomenon, prior to the rise of the use of the term tsunami in English-speaking countries, scientists generally encouraged the use of the term seismic sea wave rather than tidal wave. The Sumatran region is not unused to tsunamis either, with earthquakes of varying magnitudes regularly occurring off the coast of the island, Tsunamis are an often underestimated hazard in the Mediterranean Sea and parts of Europe. The tsunami claimed more than 123,000 lives in Sicily, the Storegga Slide in the Norwegian sea and some examples of tsunamis affecting the British Isles refer to landslide and meteotsunamis predominantly and less to earthquake-induced waves. The cause, in my opinion, of this phenomenon must be sought in the earthquake, at the point where its shock has been the most violent the sea is driven back, and suddenly recoiling with redoubled force, causes the inundation. Without an earthquake I do not see how such an accident could happen, the principal generation mechanism of a tsunami is the displacement of a substantial volume of water or perturbation of the sea. This displacement of water is attributed to either earthquakes, landslides, volcanic eruptions, glacier calvings or more rarely by meteorites. The waves formed in this way are then sustained by gravity, tides do not play any part in the generation of tsunamis. Tsunami can be generated when the sea floor abruptly deforms and vertically displaces the overlying water and they grow in height when they reach shallower water, in a wave shoaling process described below. A tsunami can occur in any state and even at low tide can still inundate coastal areas. On April 1,1946, the 8.6 Mw Aleutian Islands earthquake occurred with a maximum Mercalli intensity of VI and it generated a tsunami which inundated Hilo on the island of Hawaii with a 14-metre high surge. Between 165 and 173 were killed, the area where the earthquake occurred is where the Pacific Ocean floor is subducting under Alaska
12.
Gravity
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Gravity, or gravitation, is a natural phenomenon by which all things with mass are brought toward one another, including planets, stars and galaxies. Since energy and mass are equivalent, all forms of energy, including light, on Earth, gravity gives weight to physical objects and causes the ocean tides. Gravity has a range, although its effects become increasingly weaker on farther objects. The most extreme example of this curvature of spacetime is a hole, from which nothing can escape once past its event horizon. More gravity results in time dilation, where time lapses more slowly at a lower gravitational potential. Gravity is the weakest of the four fundamental interactions of nature, the gravitational attraction is approximately 1038 times weaker than the strong force,1036 times weaker than the electromagnetic force and 1029 times weaker than the weak force. As a consequence, gravity has an influence on the behavior of subatomic particles. On the other hand, gravity is the dominant interaction at the macroscopic scale, for this reason, in part, pursuit of a theory of everything, the merging of the general theory of relativity and quantum mechanics into quantum gravity, has become an area of research. While the modern European thinkers are credited with development of gravitational theory, some of the earliest descriptions came from early mathematician-astronomers, such as Aryabhata, who had identified the force of gravity to explain why objects do not fall out when the Earth rotates. Later, the works of Brahmagupta referred to the presence of force, described it as an attractive force. Modern work on gravitational theory began with the work of Galileo Galilei in the late 16th and this was a major departure from Aristotles belief that heavier objects have a higher gravitational acceleration. Galileo postulated air resistance as the reason that objects with less mass may fall slower in an atmosphere, galileos work set the stage for the formulation of Newtons theory of gravity. In 1687, English mathematician Sir Isaac Newton published Principia, which hypothesizes the inverse-square law of universal gravitation. Newtons theory enjoyed its greatest success when it was used to predict the existence of Neptune based on motions of Uranus that could not be accounted for by the actions of the other planets. Calculations by both John Couch Adams and Urbain Le Verrier predicted the position of the planet. A discrepancy in Mercurys orbit pointed out flaws in Newtons theory, the issue was resolved in 1915 by Albert Einsteins new theory of general relativity, which accounted for the small discrepancy in Mercurys orbit. The simplest way to test the equivalence principle is to drop two objects of different masses or compositions in a vacuum and see whether they hit the ground at the same time. Such experiments demonstrate that all objects fall at the rate when other forces are negligible
13.
Hydrostatic equilibrium
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In fluid mechanics, a fluid is said to be in hydrostatic equilibrium or hydrostatic balance when it is at rest, or when the flow velocity at each point is constant over time. This occurs when external forces such as gravity are balanced by a pressure gradient force, hydrostatic equilibrium is the current distinguishing criterion between dwarf planets and small Solar System bodies, and has other roles in astrophysics and planetary geology. This qualification typically means that the object is symmetrically rounded into a spheroid or ellipsoid shape, there are 31 observationally confirmed such objects, sometimes called planemos, in the Solar System, seven more that are virtually certain, and a hundred or so more that are likely. Newtons laws of state that a volume of a fluid that is not in motion or that is in a state of constant velocity must have zero net force on it. This means the sum of the forces in a given direction must be opposed by a sum of forces in the opposite direction. This force balance is called a hydrostatic equilibrium, the fluid can be split into a large number of cuboid volume elements, by considering a single element, the action of the fluid can be derived. If the density is ρ, the volume is V and g the standard gravity, then, the volume of this cuboid is equal to the area of the top or bottom, times the height — the formula for finding the volume of a cube. This sum equals zero if the velocity is constant. Dividing by A,0 = P b o t t o m − P t o p − ρ ⋅ g ⋅ h, or, P t o p − P b o t t o m = − ρ ⋅ g ⋅ h. Ptop − Pbottom is a change in pressure, and h is the height of the volume change in the distance above the ground. By saying these changes are small, the equation can be written in differential form. Density changes with pressure, and gravity changes with height, so the equation would be, d P = − ρ ⋅ g ⋅ d h. Note finally that this last equation can be derived by solving the three-dimensional Navier–Stokes equations for the situation where u = v = ∂ p ∂ x = ∂ p ∂ y =0. Then the only equation is the z -equation, which now reads ∂ p ∂ z + ρ g =0. Thus, hydrostatic balance can be regarded as a simple equilibrium solution of the Navier–Stokes equations. M is a foliation of spheres weighted by the mass density ρ, the hydrostatic equilibrium pertains to hydrostatics and the principles of equilibrium of fluids. A hydrostatic balance is a balance for weighing substances in water. Hydrostatic balance allows the discovery of their specific gravities, in any given layer of a star, there is a hydrostatic equilibrium between the outward thermal pressure from below and the weight of the material above pressing inward
14.
Period (physics)
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In physics, the wavelength of a sinusoidal wave is the spatial period of the wave—the distance over which the waves shape repeats, and thus the inverse of the spatial frequency. Wavelength is commonly designated by the Greek letter lambda, the concept can also be applied to periodic waves of non-sinusoidal shape. The term wavelength is also applied to modulated waves. Wavelength depends on the medium that a wave travels through, examples of wave-like phenomena are sound waves, light, water waves and periodic electrical signals in a conductor. A sound wave is a variation in air pressure, while in light and other electromagnetic radiation the strength of the electric, water waves are variations in the height of a body of water. In a crystal lattice vibration, atomic positions vary, wavelength is a measure of the distance between repetitions of a shape feature such as peaks, valleys, or zero-crossings, not a measure of how far any given particle moves. For example, in waves over deep water a particle near the waters surface moves in a circle of the same diameter as the wave height. The range of wavelengths or frequencies for wave phenomena is called a spectrum, the name originated with the visible light spectrum but now can be applied to the entire electromagnetic spectrum as well as to a sound spectrum or vibration spectrum. In linear media, any pattern can be described in terms of the independent propagation of sinusoidal components. The wavelength λ of a sinusoidal waveform traveling at constant speed v is given by λ = v f, in a dispersive medium, the phase speed itself depends upon the frequency of the wave, making the relationship between wavelength and frequency nonlinear. In the case of electromagnetic radiation—such as light—in free space, the speed is the speed of light. Thus the wavelength of a 100 MHz electromagnetic wave is about, the wavelength of visible light ranges from deep red, roughly 700 nm, to violet, roughly 400 nm. For sound waves in air, the speed of sound is 343 m/s, the wavelengths of sound frequencies audible to the human ear are thus between approximately 17 m and 17 mm, respectively. Note that the wavelengths in audible sound are much longer than those in visible light, a standing wave is an undulatory motion that stays in one place. A sinusoidal standing wave includes stationary points of no motion, called nodes, the upper figure shows three standing waves in a box. The walls of the box are considered to require the wave to have nodes at the walls of the box determining which wavelengths are allowed, the stationary wave can be viewed as the sum of two traveling sinusoidal waves of oppositely directed velocities. Consequently, wavelength, period, and wave velocity are related just as for a traveling wave, for example, the speed of light can be determined from observation of standing waves in a metal box containing an ideal vacuum. In that case, the k, the magnitude of k, is still in the same relationship with wavelength as shown above
15.
Gravity of Earth
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The gravity of Earth, which is denoted by g, refers to the acceleration that is imparted to objects due to the distribution of mass within the Earth. In SI units this acceleration is measured in metres per second squared or equivalently in newtons per kilogram and this quantity is sometimes referred to informally as little g. The precise strength of Earths gravity varies depending on location, the nominal average value at the Earths surface, known as standard gravity is, by definition,9.80665 m/s2. This quantity is denoted variously as gn, ge, g0, gee, the weight of an object on the Earths surface is the downwards force on that object, given by Newtons second law of motion, or F = ma. Gravitational acceleration contributes to the acceleration, but other factors, such as the rotation of the Earth, also contribute. The Earth is not spherically symmetric, but is slightly flatter at the poles while bulging at the Equator, there are consequently slight deviations in both the magnitude and direction of gravity across its surface. The net force as measured by a scale and plumb bob is called effective gravity or apparent gravity, effective gravity includes other factors that affect the net force. These factors vary and include such as centrifugal force at the surface from the Earths rotation. Effective gravity on the Earths surface varies by around 0. 7%, in large cities, it ranges from 9.766 in Kuala Lumpur, Mexico City, and Singapore to 9.825 in Oslo and Helsinki. The surface of the Earth is rotating, so it is not a frame of reference. At latitudes nearer the Equator, the centrifugal force produced by Earths rotation is larger than at polar latitudes. This counteracts the Earths gravity to a small degree – up to a maximum of 0. 3% at the Equator –, the same two factors influence the direction of the effective gravity. Gravity decreases with altitude as one rises above the Earths surface because greater altitude means greater distance from the Earths centre, all other things being equal, an increase in altitude from sea level to 9,000 metres causes a weight decrease of about 0. 29%. It is a misconception that astronauts in orbit are weightless because they have flown high enough to escape the Earths gravity. In fact, at an altitude of 400 kilometres, equivalent to an orbit of the Space Shuttle. Weightlessness actually occurs because orbiting objects are in free-fall, the effect of ground elevation depends on the density of the ground. A person flying at 30000 ft above sea level over mountains will feel more gravity than someone at the same elevation, however, a person standing on the earths surface feels less gravity when the elevation is higher. The following formula approximates the Earths gravity variation with altitude, g h = g 02 Where gh is the acceleration at height h above sea level
16.
Harbor
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A harbor or harbour, or haven, is a body of water where ships, boats and barges seek shelter from stormy weather, or are stored for future use. Ports are often located in harbors, harbors can be natural or artificial. An artificial harbor can have deliberately constructed breakwaters, sea walls, or jettys, or they can be constructed by dredging, in contrast, a natural harbor is surrounded on several sides by prominences of land. Examples of natural harbors include Sydney Harbour, Australia and Trincomalee Harbour in Sri Lanka, artificial harbors are frequently built for use as ports. The oldest artificial harbor known is the Ancient Egyptian site at Wadi al-Jarf, on the Red Sea coast, the largest artificially created harbor is Jebel Ali in Dubai. The Ancient Carthaginians constructed fortified, artificial harbors called cothons, a natural harbor is a landform where a part of a body of water is protected and deep enough to furnish anchorage. Natural harbors have long been of great strategic naval and economic importance, having a protected harbor reduces or eliminates the need for breakwaters as it will result in calmer waves inside the harbor. For harbors near the North and South Poles, being ice-free is an important advantage, the worlds southmost harbor, located at Antarcticas Winter Quarters Bay, is potentially ice-free, depending on the summertime pack ice conditions. Although the worlds busiest port is a hotly contested title, in 2006 the worlds busiest harbor by cargo tonnage was the Port of Shanghai
17.
Headlands and bays
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Headlands and bays are two related coastal features. Headlands and bays are found on the same coastline. A bay is a body of water, either seawater or fresh water, headlands are characterized by high, breaking waves, rocky shores, intense erosion, and steep sea cliffs. Bays generally have less activity, and often less wind activity than the areas of water outside the bay. Headlands and bays form on discordant coastlines, where the land consists of bands of rock of alternating resistance run perpendicular to the coast. Refraction of waves occurs on headlands concentrating wave energy on them, so many other landforms, such as caves, natural arches, and stacks, form on headlands. Wave energy is directed at angles to the wave crest. Orthogonals converge on headlands and diverge in bays, which concentrates wave energy on the headlands, in the formation of sea cliffs, wave erosion undercuts the slopes at the shoreline, which retreat landward. This increases the stress in the cliff-forming material and accelerates mass movement. The debris from these landslides collects at the base of the cliff and is removed by the waves, usually during storms. This debris provides sediment, which is transported through longshore current for the nearby bay, joints in the headlands are eroded back to form caves, which erode further to form arches. These gaps eventually collapse and leave tall stacks at the ends of the headlands, eventually these too are eroded by the waves. Wave refraction disperses wave energy through the bay, and along with the effect of the headlands this protects bays from storms. This effect means that the waves reaching the shore in a bay are weaker than the waves reaching the headland, through the deposition of sediment within the bay and the erosion of the headlands, coastlines eventually straighten out. But then the process starts all over again. Beaches are dynamic geologic features that can fluctuate between advancement and retreat of sediment, the natural agents of fluctuation include waves, tides, currents, and winds. Man-made elements such as the interruption of sediment supply, such as a dam, a headland bay beach can be classified as being in three different states of sedimentation. Static equilibrium refers to a beach that is stable and does not experience littoral drift or sediment deposition or erosion, waves generally diffract around the headland and near the beach when the beach is in a state of static equilibrium
18.
Estuary
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An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a zone between river environments and maritime environments. They are subject both to marine influences—such as tides, waves, and the influx of saline water—and to riverine influences—such as flows of fresh water and sediment. The inflows of sea water and fresh water provide high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world. Most existing estuaries formed during the Holocene epoch with the flooding of river-eroded or glacially scoured valleys when the sea began to rise about 10. Estuaries are typically classified according to their geomorphological features or to water-circulation patterns, the banks of many estuaries are amongst the most heavily populated areas of the world, with about 60% of the worlds population living along estuaries and the coast. The word estuary is derived from the Latin word aestuarium meaning tidal inlet of the sea, there have been many definitions proposed to describe an estuary. However, this definition excludes a number of water bodies such as coastal lagoons. This broad definition also includes fjords, lagoons, river mouths, an estuary is a dynamic ecosystem having a connection to the open sea through which the sea water enters with the rhythm of the tides. The sea water entering the estuary is diluted by the water flowing from rivers. The pattern of dilution varies between different estuaries and depends on the volume of water, the tidal range. Drowned river valleys are known as coastal plain estuaries. In places where the sea level is rising relative to the land, sea water progressively penetrates into river valleys and this is the most common type of estuary in temperate climates. Well-studied estuaries include the Severn Estuary in the United Kingdom and the Ems Dollard along the Dutch-German border, the width-to-depth ratio of these estuaries is typically large, appearing wedge-shaped in the inner part and broadening and deepening seaward. Water depths rarely exceed 30 m, examples of this type of estuary in the U. S. are the Hudson River, Chesapeake Bay, and Delaware Bay along the Mid-Atlantic coast, and Galveston Bay and Tampa Bay along the Gulf Coast. They are relatively common in tropical and subtropical locations and these estuaries are semi-isolated from ocean waters by barrier beaches. Formation of barrier beaches partially encloses the estuary, with only narrow inlets allowing contact with the ocean waters, bar-built estuaries typically develop on gently sloping plains located along tectonically stable edges of continents and marginal sea coasts. They are extensive along the Atlantic and Gulf coasts of the U. S. in areas with active coastal deposition of sediments, barrier beaches form in shallow water and are generally parallel to the shoreline, resulting in long, narrow estuaries
19.
Lake Wakatipu
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Lake Wakatipu is an inland lake in the South Island of New Zealand. It is in the southwest corner of the Otago region, near its boundary with Southland, Lake Wakatipu comes from the original Māori word Whakatipu wai-māori. With a length of 80 kilometres, it is New Zealands longest lake, the lake is also very deep, its floor being below sea level, with a maximum depth of 380 metres. It is at an altitude of 310 metres, towards the end of the Southern Alps. The general topography is a reversed N shape or dog leg, the Dart River flows into the northern end, the lake then runs south for 30 kilometres before turning abruptly to the east. Twenty kilometres further along, it sharply to the south, reaching its southern end 30 kilometres further south. The lake is drained by the Kawarau River, which flows out from the lakes Frankton Arm,8 km east of Queenstown, until about 18,000 years ago the Mataura River drained Lake Wakatipu. The Kingston Flyer follows part of the river bed now blocked by glacial moraine. Queenstown is on the shore of the lake close to eastern end of its middle section. It has a seiche of period 26.7 minutes which, in Queenstown Bay, causes the level to rise. Lake Wakatipu is renowned for its beauty, being surrounded by mountains. The Remarkables mountain range lies along its southeastern edge and it is a popular venue for adventure tourism, with skifields, paragliding, bungy jumping and tramping tracks within easy reach. A vintage steamboat, the TSS Earnslaw regularly plies its waters, several vineyards are nearby in the Gibbston Valley. The original form and meaning of the name are not known for certain, the name is believed to originate from the Waitaha people, who were later displaced by Kāti Mamoe. Taken literally, Wakatipu would mean growing canoe or possibly growing bay if the original was Whakatipu, the dialect is also known for dropping final vowels, and Wakatipua or Whakatipua have also been recorded historically, as has Wakatapu. A legend says that the bed was formed when a giant ogre. Lake Wakatipu is a habitat for the eel, brown trout, salmon. These and other fish predators such as the pied shag
20.
Queenstown, New Zealand
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Queenstown is a resort town in Otago in the south-west of New Zealands South Island. It has an population of 14,300, making it the 27th largest urban area in New Zealand. In 2016, Queenstown overtook Oamaru to become the second largest urban area in Otago, the Queenstown-Lakes District has a land area of 8,704.97 square kilometres not counting its inland lakes. The region has a resident population of 34,700. Its neighbouring towns include Arrowtown, Glenorchy, Kingston, Wanaka, Alexandra, the nearest cities are Dunedin and Invercargill. Queenstown is known for its tourism, especially adventure and ski tourism. The area was discovered and first settled by Māori before non-Māori arrived, the first non-Māori to see Lake Wakatipu was European Nathanael Chalmers who was guided by Reko, the chief of the Tuturau, over the Waimea Plains and up the Mataura River in September 1853. Evidence of stake nets, baskets for catching eels, spears and it is likely Ngāi Tahu Māori visited Queenstown en route to collect Pounamu. European explorers William Gilbert Rees and Nicholas von Tunzelmann were the first non-Maoris to settle the area, many Queenstown streets bear names from the gold mining era and some historic buildings remain. Williams Cottage, the Lake Lodge of Ophir, Queenstown Police Station, the miners and especially the Irish had taken an interest in the ceremony held for a small town called The Cove in Ireland which was renamed to Queenstown in honour of Queen Victoria in 1850. They may have had their own ceremony at the intersection of Rees, by 9 and 10 January 1863 the town was being reported with the name of Queenstown from several reports written by a correspondent in the Otago Witness on Monday the 5th and Tuesday the 6th. It was during the meeting there may have been a reference by a miner of the town being fit for a Queen, the Māori name for Queenstown of Tāhuna means shallow bay. A resort town, Queenstown boasted 220 adventure tourism activities in 2012, skiing and snowboarding, jet boating, whitewater rafting, bungy jumping, mountain biking, skateboarding, tramping, paragliding, sky diving and fly fishing are all popular. Queenstown is a centre for snow sports in New Zealand, with people from all over the country. Cross country skiing is available at the Waiorau Snowfarm, near Cardrona village. The 100-year-old twin screw coal fired steamer TSS Earnslaw traverses Lake Wakatipu, Queenstown lies close to the centre of a small wine producing region, reputed to be the worlds southernmost. The Two Paddocks vineyard is owned by local actor Sam Neill, neighbouring, historic Arrowtown features restaurants and bars. In 2013, examples include Bike Festival, Winter Festival, jane Campions six-part drama mystery Top of the Lake was shot during 2012 for pay TV release in 2013
21.
North Sea
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The North Sea is a marginal sea of the Atlantic Ocean located between Great Britain, Scandinavia, Germany, the Netherlands, Belgium, and France. An epeiric sea on the European continental shelf, it connects to the ocean through the English Channel in the south and it is more than 970 kilometres long and 580 kilometres wide, with an area of around 570,000 square kilometres. The North Sea has long been the site of important European shipping lanes as well as a major fishery, the North Sea was the centre of the Vikings rise. Subsequently, the Hanseatic League, the Netherlands, and the British each sought to dominate the North Sea and thus the access to the markets, as Germanys only outlet to the ocean, the North Sea continued to be strategically important through both World Wars. The coast of the North Sea presents a diversity of geological and geographical features, in the north, deep fjords and sheer cliffs mark the Norwegian and Scottish coastlines, whereas in the south it consists primarily of sandy beaches and wide mudflats. Due to the population, heavy industrialization, and intense use of the sea and area surrounding it. In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean, in the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively. In the north it is bordered by the Shetland Islands, and connects with the Norwegian Sea, the North Sea is more than 970 kilometres long and 580 kilometres wide, with an area of 570,000 square kilometres and a volume of 54,000 cubic kilometres. Around the edges of the North Sea are sizeable islands and archipelagos, including Shetland, Orkney, the North Sea receives freshwater from a number of European continental watersheds, as well as the British Isles. A large part of the European drainage basin empties into the North Sea including water from the Baltic Sea, the largest and most important rivers flowing into the North Sea are the Elbe and the Rhine – Meuse watershed. Around 185 million people live in the catchment area of the rivers discharging into the North Sea encompassing some highly industrialized areas, for the most part, the sea lies on the European continental shelf with a mean depth of 90 metres. The only exception is the Norwegian trench, which extends parallel to the Norwegian shoreline from Oslo to a north of Bergen. It is between 20 and 30 kilometres wide and has a depth of 725 metres. The Dogger Bank, a vast moraine, or accumulation of unconsolidated glacial debris and this feature has produced the finest fishing location of the North Sea. The Long Forties and the Broad Fourteens are large areas with uniform depth in fathoms. These great banks and others make the North Sea particularly hazardous to navigate, the Devils Hole lies 200 miles east of Dundee, Scotland. The feature is a series of trenches between 20 and 30 kilometres long,1 and 2 kilometres wide and up to 230 metres deep. Other areas which are less deep are Cleaver Bank, Fisher Bank, the International Hydrographic Organization defines the limits of the North Sea as follows, On the Southwest
22.
Lake Erie
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Lake Erie is the fourth-largest lake of the five Great Lakes in North America, and the thirteenth-largest globally if measured in terms of surface area. It is the southernmost, shallowest, and smallest by volume of the Great Lakes, at its deepest point Lake Erie is 210 feet deep. Lake Eries northern shore is bounded by the Canadian province of Ontario, with the U. S. states of Ohio, Pennsylvania and these jurisdictions divide the surface area of the lake by water boundaries. The lake was named by the Erie people, a Native Americans people who lived along its southern shore and that Iroquoian tribe called it Erige because of its unpredictable and sometimes violently dangerous nature. It is a matter of whether the lake was named after the tribe. Situated below Lake Huron, Eries primary inlet is the Detroit River, Lake Erie has a mean elevation of 571 feet above sea level. It has an area of 9,990 square miles with a length of 241 statute miles. The warm summer of 1999 caused lake temperatures to come close to the 85 °F limit necessary to keep the plants cool, also because of its shallowness, and in spite of being the warmest lake in the summer, it is also the first to freeze in the winter. The waves build very quickly, according to other accounts, after being trapped for an hour-and-a-half, Baker was back on dry land, exhausted and battered but alive. This area is known as the thunderstorm capital of Canada with breathtaking lightning displays. Lake Erie is primarily fed by the Detroit River and drains via the Niagara River, navigation downstream is provided by the Welland Canal, part of the Saint Lawrence Seaway. Other major contributors to Lake Erie include the Grand River, the Huron River, the Maumee River, the Sandusky River, the Buffalo River, the drainage basin covers 30,140 square miles. Point Pelee National Park, the southernmost point of the Canadian mainland, is located on a peninsula extending into the lake. Several islands are found in the end of the lake, these belong to Ohio except for Pelee Island and eight neighboring islands. Major cities along Lake Erie include Buffalo, Erie, Pennsylvania, Toledo, Ohio, Islands tend to be located in the western side of the lake and total 31 in number. The island-village of Put-in-Bay on South Bass Island attracts young crowds who sometimes wear red hats and are prone to break off cartwheels in the park. Pelee Island is the largest of Eries islands, accessible by ferry from Leamington, Ontario and Sandusky, songbirds migrate to Pelee in spring, and monarch butterflies stop over during the fall. Lake Erie has a retention time of 2.6 years
23.
Buffalo, New York
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Buffalo is a city in western New York state and the county seat of Erie County, on the eastern shores of Lake Erie at the head of the Niagara River. As of 2014, Buffalo is New York states 2nd-most populous city after New York City, the metropolitan area has a population of 1.13 million. After an economic downturn in the half of the 20th century, Buffalos economy has transitioned to sectors that include financial services, technology, biomedical engineering. Residents of Buffalo are called Buffalonians, the citys nicknames include The Queen City, The Nickel City and The City of Good Neighbors. The city of Buffalo received its name from a creek called Buffalo Creek. British military engineer Captain John Montresor made reference to Buffalo Creek in his journal of 1764, there are several theories regarding how Buffalo Creek received its name. In 1804, as principal agent opening the area for the Holland Land Company, Joseph Ellicott, designed a radial street and grid system that branches out from downtown like bicycle spokes similar to the street system he used in the nations capital. Although Ellicott named the settlement New Amsterdam, the name did not catch on, during the War of 1812, on December 30,1813, Buffalo was burned by British forces. The George Coit House 1818 and Samuel Schenck House 1823 are currently the oldest houses within the limits of the City of Buffalo, on October 26,1825, the Erie Canal was completed with Buffalo a port-of-call for settlers heading westward. At the time, the population was about 2,400, the Erie Canal brought about a surge in population and commerce, which led Buffalo to incorporate as a city in 1832. In 1845, construction began on the Macedonia Baptist Church, an important meeting place for the abolitionist movement, Buffalo was a terminus point of the Underground Railroad with many fugitive slaves crossing the Niagara River to Fort Erie, Ontario in search of freedom. During the 1840s, Buffalos port continued to develop, both passenger and commercial traffic expanded with some 93,000 passengers heading west from the port of Buffalo. Grain and commercial goods shipments led to repeated expansion of the harbor, in 1843, the worlds first steam-powered grain elevator was constructed by local merchant Joseph Dart and engineer Robert Dunbar. Darts Elevator enabled faster unloading of lake freighters along with the transshipment of grain in bulk from barges, canal boats, by 1850, the citys population was 81,000. At the dawn of the 20th century, local mills were among the first to benefit from hydroelectric power generated by the Niagara River, the city got the nickname City of Light at this time due to the widespread electric lighting. It was also part of the revolution, hosting the brass era car builders Pierce Arrow. President William McKinley was shot and mortally wounded by an anarchist at the Pan-American Exposition in Buffalo on September 6,1901, McKinley died in the city eight days later and Theodore Roosevelt was sworn in at the Wilcox Mansion as the 26th President of the United States. The Great Depression of 1929–39 saw severe unemployment, especially working class men
24.
Toledo, Ohio
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Toledo is a city in and the county seat of Lucas County, Ohio, United States. Toledo is in northwest Ohio, at the end of Lake Erie bordering the state of Michigan. The city was founded by United States citizens in 1833 on the west bank of the Maumee River and it was re-founded in 1837, after conclusion of the Toledo War, when it was incorporated in Ohio. After construction of the Miami and Erie Canal, Toledo grew quickly and it has since become a city with an art community, auto assembly businesses, education, healthcare, and local sports teams. The citys glass industry has earned it the nickname, The Glass City, the population of Toledo as of the 2010 Census was 287,208, making it the 71st-largest city in the United States. It is the fourth most populous city in the U. S. state of Ohio after Columbus, Cleveland, and Cincinnati. The Toledo metropolitan area had a 2010 population of 651,429, and was the sixth-largest metropolitan area in the state of Ohio, behind Cleveland, Columbus, Cincinnati, Dayton, and Akron. Varying cultures of indigenous peoples lived along the rivers and lakefront of what is now northwestern Ohio for thousands of years, when the city of Toledo was preparing to pave its streets, it surveyed two prehistoric semicircular earthworks, presumably for stockades. One was at the intersection of Clayton and Oliver streets on the bank of Swan Creek. Such earthworks were typical of mound-building peoples and this region was part of a larger area controlled by the historic tribes of the Wyandot and the people of the Council of Three Fires. The first European to visit the area was Étienne Brûlé, a French-Canadian guide and explorer, the French established trading posts in the area by 1680 to take advantage of the lucrative fur trade. The Odawa moved from Manitoulin Island and the Bruce Peninsula at the invitation of the French and they settled an area extending into northwest Ohio. By the early 18th century, the Odawa occupied areas along most of the Maumee River to its mouth and they served as middlemen between the French and tribes further to the west and north. The Wyandot occupied central Ohio, and the Shawnee and Lenape occupied the southern areas, the area was not settled by European-Americans until 1795 and after. They were finally defeated in 1794 at the Battle of Fallen Timbers and this loose affiliation of tribes included the Wyandot and Council of Three Fires. By a treaty in 1795, they ceded large areas of territory in Ohio to the United States, according to Charles E. Slocum, the American military built Fort Industry at the mouth of the Maumee about 1805, but as a temporary stockade. No official reports support the 19th-century tradition of its history there. The United States continued to work to extinguish land claims of Native Americans, in the Treaty of Detroit, the above four tribes ceded a large land area to the United States of what became southeastern Michigan and northwestern Ohio, to the mouth of the Maumee River
25.
National Weather Service
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It is a part of the National Oceanic and Atmospheric Administration branch of the Department of Commerce, and is headquartered in Silver Spring, Maryland. The agency was known as the United States Weather Bureau from 1890 until it adopted its current name in 1970, the NWS performs its primary task through a collection of national and regional centers, and 122 local weather forecast offices. As the NWS is a government agency, most of its products are in the public domain, the agency was placed under the Secretary of War as Congress felt military discipline would probably secure the greatest promptness, regularity, and accuracy in the required observations. Within the Department of War, it was assigned to the U. S. Army Signal Service under Brigadier General Albert J. Myer, General Myer gave the National Weather Service its first name, The Division of Telegrams and Reports for the Benefit of Commerce. The agency first became an enterprise in 1890, when it became part of the Department of Agriculture. The first Weather Bureau radiosonde was launched in Massachusetts in 1937, the Bureau would later be moved to the Department of Commerce in 1940. On July 12,1950, bureau chief Francis W, the Weather Bureau became part of the Environmental Science Services Administration when that agency was formed in August 1966. The Environmental Science Services Administration was renamed the National Oceanic and Atmospheric Administration on October 1,1970, at this time, the Weather Bureau became the National Weather Service. NEXRAD, a system of Doppler radars deployed to improve the detection and warning time of local storms, replaced the WSR-57. Bob Glahn has written a history of the first hundred years of the National Weather Service. The NWS, through a variety of sub-organizations, issues different forecast products to users, although, throughout history, text forecasts have been the means of product dissemination, the NWS has been using more forecast products of a digital, gridded, image or other modern format. Each of the 122 Weather Forecast Offices send their graphical forecasts to a server to be compiled in the National Digital Forecast Database. The NDFD is a collection of weather observations used by organizations and the public, including precipitation amount, temperature. Specific points in the database can be accessed using an XML SOAP service. The National Weather Service issues many products relating to wildfires daily, for example, a Fire Weather Forecast, which have a forecast period covering up to seven days, is issued by local Weather Forecast Offices daily, with updates as needed. The forecasts contain weather information relevant to fire control and smoke management for the next 12 to 48 hours, such as direction and speed. The appropriate crews use this information to plan for staffing and equipment levels, the ability to conduct scheduled controlled burns, and assess the daily fire danger. Once per day, NWS meteorologists issue a coded fire weather forecast for specific United States Forest Service observation sites that are input into the National Fire Danger Rating System
26.
Fetch (geography)
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The fetch, also called the fetch length, is the length of water over which a given wind has blown. It also plays a part in longshore drift as well. Fetch length, along with the speed, determines the size of waves produced. The wind direction is considered constant, the longer the fetch and the faster the wind speed, the more wind energy is imparted to the water surface and the larger the resulting sea state will be. Sea state Ocean surface wave Storm surge
27.
Storm surge
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Most casualties during tropical cyclones occur as the result of storm surges. The deadliest storm surge on record was the 1970 Bhola cyclone, the low-lying coast of the Bay of Bengal is particularly vulnerable to surges caused by tropical cyclones. The deadliest storm surge in the twenty-first century was caused by the Cyclone Nargis, the next deadliest in this century was caused by the Typhoon Haiyan, which killed more than 6,000 people in the central Philippines in 2013 and resulted in economic losses estimated at $14 billion. Louis, Diamondhead and Pass Christian in Mississippi, a high storm surge occurred in New York City from Hurricane Sandy in October 2012, with a high tide of 14 ft. The pressure effects of a tropical cyclone will cause the level in the open ocean to rise in regions of low atmospheric pressure. The rising water level will counteract the low pressure such that the total pressure at some plane beneath the water surface remains constant. This effect is estimated at a 10 mm increase in sea level for every millibar drop in atmospheric pressure, strong surface winds cause surface currents at a 45° angle to the wind direction, by an effect known as the Ekman Spiral. Wind stresses cause a phenomenon referred to as wind set-up, which is the tendency for water levels to increase at the downwind shore, intuitively, this is caused by the storm simply blowing the water towards one side of the basin in the direction of its winds. Because the Ekman Spiral effects spread vertically through the water, the effect is proportional to depth. The pressure effect and the wind set-up on an open coast will be driven into bays in the way as the astronomical tide. The Earths rotation causes the Coriolis effect, which bends currents to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. When this bend brings the currents into more contact with the shore it can amplify the surge. The effect of waves, while powered by the wind, is distinct from a storms wind-powered currents. Powerful wind whips up large, strong waves in the direction of its movement, although these surface waves are responsible for very little water transport in open water, they may be responsible for significant transport near the shore. When waves are breaking on a more or less parallel to the beach. The rainfall effect is experienced predominantly in estuaries, Hurricanes may dump as much as 12 in of rainfall in 24 hours over large areas, and higher rainfall densities in localized areas. As a result, watersheds can quickly surge water into the rivers that drain them and this can increase the water level near the head of tidal estuaries as storm-driven waters surging in from the ocean meet rainfall flowing from the estuary. This situation well exemplified by the southeast coast of Florida
28.
Hurricane Hazel
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Hurricane Hazel was the deadliest and costliest hurricane of the 1954 Atlantic hurricane season. The storm killed at least 400 people in Haiti before striking the United States near the border between North and South Carolina, as a Category 4 hurricane. After causing 95 fatalities in the US, Hazel struck Canada as a storm, raising the death toll by 81 people. As a result of the death toll and the damage caused by Hazel. In Haiti, Hazel destroyed 40% of the trees and 50% of the cacao crop. The hurricane made landfall in the Carolinas, and destroyed most waterfront dwellings near its point of impact, from North Carolina, it traveled north along the Atlantic coast. Hazel affected Virginia, West Virginia, Maryland, Delaware, New Jersey, Pennsylvania, when it was over Pennsylvania, Hazel consolidated with a cold front, and turned northwest towards Canada. When it hit Ontario as a storm, rivers and streams in and around Toronto overflowed their banks. As a result, many areas located in the local floodplains. In Canada alone, over C$135 million of damage was incurred, Hazel had traveled 1,100 km over land, but while approaching Canada, it had merged with an existing powerful cold front. The storm stalled over the Greater Toronto Area, and although it was now extratropical, to help with the cleanup,800 members of the military were summoned, and a Hurricane Relief Fund was established that distributed $5.1 million in aid. On October 5, a wave with tropical-storm force winds was approaching the Lesser Antilles. Due to the potential for storm formation, a Hurricane Hunters plane flew from San Juan. When the plane reached the system, they observed a tropical cyclone about 30 mi east of the island of Grenada with winds estimated at 100 mph, the United States Weather Bureau promptly classified the system as Hurricane Hazel. The Atlantic hurricane reanalysis later assessed that Hazel developed at 06,00 UTC on October 5 about 220 mi east of Grenada. Although the Hurricane Hunters observed hurricane-force winds, the storm had a small eye 5 mi in diameter and a central barometric pressure of 1,002 mbar. The 100 mph winds were therefore revised downward to 65 mph late on October 5, at the same time, Hazel made landfall on Grenada with winds of 75 mph. After entering the Caribbean Sea, Hazel continued to present a small eye, the winds gradually increased as the storm moved westward, parallel to the northern Venezuela coast
29.
Lake Ontario
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Lake Ontario is one of the five Great Lakes of North America. Ontario, Canadas most populous province, was named for the lake, in the Wyandot language, ontarío means “Lake of Shining Waters”. Its primary inlet is the Niagara River from Lake Erie, the last in the Great Lakes chain, Lake Ontario serves as the outlet to the Atlantic Ocean via the St. Lawrence River. Lake Ontario is the easternmost of the Great Lakes and the smallest in surface area and it is the 14th largest lake in the world. When its islands are included, the lake has a shoreline that is 712 miles long. As the last lake in the Great Lakes hydrologic chain, Lake Ontario has the lowest mean elevation of the lakes at 243 feet above sea level,326 feet lower than its neighbor upstream. Its maximum length is 193 statute miles and its width is 53 statute miles. The lakes average depth is 47 fathoms 1 foot, with a depth of 133 fathoms 4 feet. The lakes primary source is the Niagara River, draining Lake Erie, the drainage basin covers 24,720 square miles. As with all the Great Lakes, water levels both within the year and among years. These water level fluctuations are a part of lake ecology. The lake also has an important freshwater fishery, although it has negatively affected by factors including over-fishing, water pollution. Baymouth bars built by prevailing winds and currents have created a significant number of lagoons and sheltered harbors, mostly near Prince Edward County, Ontario, perhaps the best-known example is Toronto Bay, chosen as the site of the Upper Canada capital for its strategic harbour. Other prominent examples include Hamilton Harbour, Irondequoit Bay, Presquile Bay, the bars themselves are the sites of long beaches, such as Sandbanks Provincial Park and Sandy Island Beach State Park. These sand bars are associated with large wetlands, which support large numbers of plant and animal species. Presquile, on the shore of Lake Ontario, is particularly significant in this regard. The lake basin was carved out of soft, weak Silurian-age rocks by the Wisconsin ice sheet during the last ice age, the action of the ice occurred along the pre-glacial Ontarian River valley which had approximately the same orientation as todays basin. As the ice sheet retreated toward the north, it still dammed the St. Lawrence valley outlet and this stage is known as Lake Iroquois
30.
Toronto
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Toronto is the most populous city in Canada and the provincial capital of Ontario. With a population of 2,731,571, it is the fourth most populous city in North America after Mexico City, New York City, and Los Angeles. A global city, Toronto is a centre of business, finance, arts, and culture. Aboriginal peoples have inhabited the area now known as Toronto for thousands of years, the city itself is situated on the southern terminus of an ancient Aboriginal trail leading north to Lake Simcoe, used by the Wyandot, Iroquois, and the Mississauga. Permanent European settlement began in the 1790s, after the broadly disputed Toronto Purchase of 1787, the British established the town of York, and later designated it as the capital of Upper Canada. During the War of 1812, the town was the site of the Battle of York, York was renamed and incorporated as the city of Toronto in 1834, and became the capital of the province of Ontario during the Canadian Confederation in 1867. The city proper has since expanded past its original borders through amalgamation with surrounding municipalities at various times in its history to its current area of 630.2 km2. While the majority of Torontonians speak English as their primary language, Toronto is a prominent centre for music, theatre, motion picture production, and television production, and is home to the headquarters of Canadas major national broadcast networks and media outlets. Toronto is known for its skyscrapers and high-rise buildings, in particular the tallest free-standing structure in the Western Hemisphere. The name Toronto is likely derived from the Iroquois word tkaronto and this refers to the northern end of what is now Lake Simcoe, where the Huron had planted tree saplings to corral fish. A portage route from Lake Ontario to Lake Huron running through this point, in the 1660s, the Iroquois established two villages within what is today Toronto, Ganatsekwyagon on the banks of the Rouge River and Teiaiagonon the banks of the Humber River. By 1701, the Mississauga had displaced the Iroquois, who abandoned the Toronto area at the end of the Beaver Wars, French traders founded Fort Rouillé on the current Exhibition grounds in 1750, but abandoned it in 1759. During the American Revolutionary War, the region saw an influx of British settlers as United Empire Loyalists fled for the British-controlled lands north of Lake Ontario, the new province of Upper Canada was in the process of creation and needed a capital. Dorchester intended the location to be named Toronto, in 1793, Governor John Graves Simcoe established the town of York on the Toronto Purchase lands, instead naming it after Prince Frederick, Duke of York and Albany. Simcoe decided to move the Upper Canada capital from Newark to York, the York garrison was constructed at the entrance of the towns natural harbour, sheltered by a long sandbar peninsula. The towns settlement formed at the end of the harbour behind the peninsula, near the present-day intersection of Parliament Street. In 1813, as part of the War of 1812, the Battle of York ended in the towns capture, the surrender of the town was negotiated by John Strachan. US soldiers destroyed much of the garrison and set fire to the parliament buildings during their five-day occupation, the sacking of York was a primary motivation for the Burning of Washington by British troops later in the war
31.
Lake Superior
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Lake Superior is the largest of the Great Lakes of North America. The lake is shared by the Canadian province of Ontario to the north, the US state of Minnesota to the west and it is generally considered the largest freshwater lake in the world by surface area. It is the worlds third-largest freshwater lake by volume and the largest by volume in North America, the Ojibwe call the lake gichi-gami, meaning be a great sea. Henry Wadsworth Longfellow wrote the name as Gitche Gumee in The Song of Hiawatha, as did Gordon Lightfoot in his song, according to other sources the actual Ojibwe name is Ojibwe Gichigami or Anishinaabe Gichigami. The 1878 dictionary by Father Frederic Baraga, the first one written for the Ojibway language, the first French explorers approaching the great inland sea by way of the Ottawa River and Lake Huron during the 17th century referred to their discovery as le lac supérieur. Properly translated, the expression means Upper Lake, that is, the lake was also called Lac Tracy by 17th century Jesuit missionaries. Lake Superior empties into Lake Huron via the St. Marys River, Lake Superior is the largest freshwater lake in the world in area, and the third largest in volume, behind Lake Baikal in Siberia and Lake Tanganyika in East Africa. Lake Superior has an area of 31,700 square miles. It has a length of 350 statute miles and maximum breadth of 160 statute miles. Its average depth is 80.5 fathoms with a depth of 222.17 fathoms. Lake Superior contains 2,900 cubic miles of water, there is enough water in Lake Superior to cover the entire land mass of North and South America to a depth of 30 centimetres. The shoreline of the lake stretches 2,726 miles, while the temperature of the surface of Lake Superior varies seasonally, the temperature below 110 fathoms is an almost constant 39 °F. This variation in temperature makes the lake seasonally stratigraphic, twice per year, however, the water column reaches a uniform temperature of 39 °F from top to bottom, and the lake waters thoroughly mix. This feature makes the lake dimictic, because of its volume, Lake Superior has a retention time of 191 years. Annual storms on Lake Superior regularly feature wave heights of over 20 feet, waves well over 30 feet have been recorded. The lake is fed by over 200 rivers, the largest include the Nipigon River, the St. Louis River, the Pigeon River, the Pic River, the White River, the Michipicoten River, the Bois Brule River and the Kaministiquia River. Lake Superior drains into Lake Huron via the St. Marys River, there are rapids at the rivers upper end where the river bed has a relatively steep gradient. The Soo Locks were built to enable ships to bypass the rapids, the lakes average surface elevation is 600 feet above sea level
32.
Lake Huron
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Lake Huron is one of the five Great Lakes of North America. It is shared on the north and east by the Canadian province of Ontario and on the south, the name of the lake is derived from early French explorers who named it for the Huron people inhabiting the region. The Huronian glaciation was named due to evidence collected from Lake Huron region, the northern parts of the lake include the North Channel and Georgian Bay. Across the lake to the southwest is Saginaw Bay, the main inlet is the St. Marys River and the main outlet is the St. Clair. By volume however, Lake Huron is only the third largest of the Great Lakes, being surpassed by Lake Michigan, when measured at the low water datum, the lake contains a volume of 850 cubic miles and a shoreline length of 3,827 mi. The surface of Lake Huron is 577 feet above sea level, the lakes average depth is 32 fathoms 3 feet, while the maximum depth is 125 fathoms. It has a length of 206 statute miles and a greatest breadth of 183 statute miles. Cities with over 10,000 people on Lake Huron include Sarnia, the largest city on Lake Huron, and Saugeen Shores in Canada and Bay City, Port Huron, a large bay that protrudes northeast from Lake Huron into Ontario, Canada, is called Georgian Bay. A notable feature of the lake is Manitoulin Island, which separates the North Channel and it is the worlds largest freshwater island. Major centres on Georgian Bay include Owen Sound, Wasaga Beach, Midland, Penetanguishene, Port Severn, a smaller bay that protrudes southwest from Lake Huron into Michigan is called Saginaw Bay. Historic High Water The lake fluctuates from month to month with the highest lake levels in October and November, the normal high-water mark is 2.00 feet above datum. In the summer of 1986, Lakes Michigan and Huron reached their highest level at 5.92 feet above datum, the high-water records began in February 1986 and lasted through the year, ending with January 1987. Water levels ranged from 3.67 to 5.92 feet above Chart Datum, historic Low Water Lake levels tend to be the lowest in winter. The normal low-water mark is 1.00 foot below datum, in the winter of 1964, Lakes Michigan and Huron reached their lowest level at 1.38 feet below datum. As with the records, monthly low-water records were set each month from February 1964 through January 1965. During this twelve-month period, water levels ranged from 1.38 to 0.71 feet below Chart Datum, the Great Lakes Circle Tour is a designated scenic road system connecting all the Great Lakes and the St. Lawrence River. Lake Huron has the largest shore line length of any of the Great Lakes, Lake Huron is separated from Lake Michigan, which lies at the same level, by the 5-mile-wide, 20-fathom-deep Straits of Mackinac, making them hydrologically the same body of water. Aggregated, Lake Huron-Michigan, at 45,300 square miles, is technically the worlds largest freshwater lake, when counted separately, Lake Superior is 8,700 square miles larger than Huron and higher
33.
Port Huron, Michigan
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Port Huron is a city in the U. S. state of Michigan and the county seat of St. Clair County. The population was 30,184 at the 2010 census, the city is adjacent to Port Huron Township but is administratively autonomous. Located along the St. Clair River, it is connected to Point Edward, the city lies at the southern end of Lake Huron and is the easternmost point on land in Michigan. Port Huron is home to two mills, Mueller Brass, and many businesses related to tourism and the automotive industry. The city features a downtown area, boardwalk, marina, museum, lighthouse. In 1814 following the War of 1812, the United States established Fort Gratiot at the base of Lake Huron, French colonists had a temporary trading post and fort at this site in the 17th century, but this developed as the first settled European-American population in the area. Until 1836, an Ojibwa reservation occupied land in part of the area of Port Huron. They were removed to west of the Mississippi in Wisconsin and Minnesota, in 1857, Port Huron became incorporated. Its population grew rapidly after the 1850s due a high rate of immigration attracted by the successful shipbuilding, in 1859 the city had a total of 4.031 residents,1855 were of foreign birth or their children. By 1870, Port Hurons population exceeded that of surrounding villages, in 1871, the State Supreme Court designated Port Huron as the county seat. On October 8,1871, the city, as well as places north in Sanilac and Huron counties, a series of other fires leveled Holland and Manistee, Michigan, as well as Peshtigo, Wisconsin and Chicago on the same day. The Thumb Fire that occurred a decade later, also engulfed Port Huron, in 1895 the village of Fort Gratiot, in the vicinity of the former Fort Gratiot, was annexed by the city of Port Huron. The following historic sites have been recognized by the State of Michigan through its historic marker program, the fort was built in 1686 by the French explorer Duluth. This fort was the second European settlement in lower Michigan and this post guarded the upper end of the St. Clair River, the vital waterway joining Lake Erie and Lake Huron. Intended by the French to bar English traders from the upper lakes, in 1688 the French abandoned this fort. The site was incorporated into Fort Gratiot in 1814, a park has been established at the former site of the fort. The Fort Gratiot Lighthouse was built in 1829 to replace a tower destroyed by a storm, in the 1860s workers extended the tower to its present height of 84 feet. The light, automated in 1933, continues to guide shipping on Lake Huron into the narrow and it was the first lighthouse established in the State of Michigan
34.
Lake Michigan
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Lake Michigan is one of the five Great Lakes of North America and the only one located entirely within the United States. The other four Great Lakes are shared by the U. S. and it is the second-largest of the Great Lakes by volume and the third-largest by surface area, after Lake Superior and Lake Huron. Lake Michigan is shared, from west to east, by the U. S. states of Wisconsin, Illinois, Indiana, ports along its shores include Chicago, Milwaukee, Green Bay, Wisconsin, Gary, Indiana, and Benton Harbor, Michigan. The word Michigan originally referred to the lake itself, and is believed to come from the Ojibwa word mishigami meaning great water, some of the earliest human inhabitants of the Lake Michigan region were the Hopewell Indians. Their culture declined after 800 AD, and for the few hundred years. The French explorer Jean Nicolet is believed to have been the first European to reach Lake Michigan, in the earliest European maps of the region, the name of Lake Illinois has been found in addition to that of Michigan, named for the Illinois Confederation of tribes. Lake Michigan is joined via the narrow, open-water Straits of Mackinac with Lake Huron, the Straits of Mackinac were an important Native American and fur trade route. The eastern end of the Straits was controlled by Fort Mackinac on Mackinac Island, French coureurs des bois and voyageurs established small ports and trading communities, such as Green Bay, on the lake during the late 17th and early 18th centuries. In the 19th century, Lake Michigan played a role in the development of Chicago. The first person to reach the bottom of Lake Michigan was J. Val Klump. Klump reached the bottom via submersible as part of a 1985 research expedition, in 2007, a row of stones paralleling an ancient shoreline was discovered by Mark Holley, professor of underwater archeology at Northwestern Michigan College. This formation lies 40 feet below the surface of the lake, One of the stones is said to have a carving resembling a mastodon. So far the formation has not been authenticated, Lake Michigan is the only one of the Great Lakes wholly within the borders of the United States, the others are shared with Canada. It lies in the known as the American Midwest. Lake Michigan has an area of 22,404 sq. mi, making it the largest lake entirely within one country by surface area. It is the half of Lake Michigan–Huron, which is the largest body of fresh water in the world. It is 307 miles long by 118 miles wide with a shoreline 1,640 miles long, the lakes average depth is 46 fathoms 3 feet, while its greatest depth is 153 fathoms 5 feet. It contains a volume of 1,180 cubic miles of water, Green Bay in the northwest is its largest bay
35.
Chicago
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Chicago, officially the City of Chicago, is the third-most populous city in the United States. With over 2.7 million residents, it is the most populous city in the state of Illinois, and it is the county seat of Cook County. In 2012, Chicago was listed as a global city by the Globalization and World Cities Research Network. Chicago has the third-largest gross metropolitan product in the United States—about $640 billion according to 2015 estimates, the city has one of the worlds largest and most diversified economies with no single industry employing more than 14% of the workforce. In 2016, Chicago hosted over 54 million domestic and international visitors, landmarks in the city include Millennium Park, Navy Pier, the Magnificent Mile, Art Institute of Chicago, Museum Campus, the Willis Tower, Museum of Science and Industry, and Lincoln Park Zoo. Chicagos culture includes the arts, novels, film, theater, especially improvisational comedy. Chicago also has sports teams in each of the major professional leagues. The city has many nicknames, the best-known being the Windy City, the name Chicago is derived from a French rendering of the Native American word shikaakwa, known to botanists as Allium tricoccum, from the Miami-Illinois language. The first known reference to the site of the current city of Chicago as Checagou was by Robert de LaSalle around 1679 in a memoir, henri Joutel, in his journal of 1688, noted that the wild garlic, called chicagoua, grew abundantly in the area. In the mid-18th century, the area was inhabited by a Native American tribe known as the Potawatomi, the first known non-indigenous permanent settler in Chicago was Jean Baptiste Point du Sable. Du Sable was of African and French descent and arrived in the 1780s and he is commonly known as the Founder of Chicago. In 1803, the United States Army built Fort Dearborn, which was destroyed in 1812 in the Battle of Fort Dearborn, the Ottawa, Ojibwe, and Potawatomi tribes had ceded additional land to the United States in the 1816 Treaty of St. Louis. The Potawatomi were forcibly removed from their land after the Treaty of Chicago in 1833, on August 12,1833, the Town of Chicago was organized with a population of about 200. Within seven years it grew to more than 4,000 people, on June 15,1835, the first public land sales began with Edmund Dick Taylor as U. S. The City of Chicago was incorporated on Saturday, March 4,1837, as the site of the Chicago Portage, the city became an important transportation hub between the eastern and western United States. Chicagos first railway, Galena and Chicago Union Railroad, and the Illinois, the canal allowed steamboats and sailing ships on the Great Lakes to connect to the Mississippi River. A flourishing economy brought residents from rural communities and immigrants from abroad, manufacturing and retail and finance sectors became dominant, influencing the American economy. The Chicago Board of Trade listed the first ever standardized exchange traded forward contracts and these issues also helped propel another Illinoisan, Abraham Lincoln, to the national stage
36.
Lake Tahoe
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Lake Tahoe is a large freshwater lake in the Sierra Nevada of the United States. Lying at 6,225 ft, it straddles the border between California and Nevada, west of Carson City. Lake Tahoe is the largest alpine lake in North America, and its depth is 1,645 ft, making it the second deepest in the United States after Crater Lake in Oregon. The lake was formed about 2 million years ago as part of the Lake Tahoe Basin and it is known for the clarity of its water and the panorama of surrounding mountains on all sides. The area surrounding the lake is referred to as Lake Tahoe. More than 75% of the watershed is national forest land. Lake Tahoe is a major tourist attraction in both Nevada and California and it is home to winter sports, summer outdoor recreation, and scenery enjoyed throughout the year. Snow and ski resorts are a significant part of the areas economy, the Nevada side also offers large casinos, with highways providing year-round access to the entire area. It is about 22 mi long and 12 mi wide and has 72 mi of shoreline, approximately two-thirds of the shoreline is in California. Although highways run within sight of the shore for much of Tahoes perimeter. The Lake Tahoe Watershed of 505 sq mi includes the area that drains to the lake. Lake Tahoe is fed by 63 tributaries and these drain an area about the same size as the lake and produce half its water, with the balance entering as rain or snow falling directly on it. The Truckee River is the only outlet, flowing northeast through Reno, Nevada. It accounts for one third of the water leaves the lake. The flow of the Truckee River and the height of the lake are controlled by the Lake Tahoe Dam at the outlet, the natural rim is at 6,223 ft above sea level, with a spillway at the dam controlling overflow. The maximum legal limit, to which the lake can be allowed to rise in order to water, is at 6,229.1 ft. Around New Year 1996/1997 a Pineapple Express atmospheric river melted snow and caused the lake and river to overflow, inundating Reno, the Lake Tahoe Basin was formed by vertical motion faulting. Uplifted blocks created the Carson Range on the east and the main Sierra Nevada crest on the west, down-dropped blocks created the Lake Tahoe Basin in between
37.
California
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California is the most populous state in the United States and the third most extensive by area. Located on the western coast of the U. S, California is bordered by the other U. S. states of Oregon, Nevada, and Arizona and shares an international border with the Mexican state of Baja California. Los Angeles is Californias most populous city, and the second largest after New York City. The Los Angeles Area and the San Francisco Bay Area are the nations second- and fifth-most populous urban regions, California also has the nations most populous county, Los Angeles County, and its largest county by area, San Bernardino County. The Central Valley, an agricultural area, dominates the states center. What is now California was first settled by various Native American tribes before being explored by a number of European expeditions during the 16th and 17th centuries, the Spanish Empire then claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its war for independence. The western portion of Alta California then was organized as the State of California, the California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom. If it were a country, California would be the 6th largest economy in the world, fifty-eight percent of the states economy is centered on finance, government, real estate services, technology, and professional, scientific and technical business services. Although it accounts for only 1.5 percent of the states economy, the story of Calafia is recorded in a 1510 work The Adventures of Esplandián, written as a sequel to Amadis de Gaula by Spanish adventure writer Garci Rodríguez de Montalvo. The kingdom of Queen Calafia, according to Montalvo, was said to be a land inhabited by griffins and other strange beasts. This conventional wisdom that California was an island, with maps drawn to reflect this belief, shortened forms of the states name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, various estimates of the native population range from 100,000 to 300,000. The Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups also were diverse in their organization with bands, tribes, villages. Trade, intermarriage and military alliances fostered many social and economic relationships among the diverse groups, the first European effort to explore the coast as far north as the Russian River was a Spanish sailing expedition, led by Portuguese captain Juan Rodríguez Cabrillo, in 1542. Some 37 years later English explorer Francis Drake also explored and claimed a portion of the California coast in 1579. Spanish traders made unintended visits with the Manila galleons on their trips from the Philippines beginning in 1565
38.
Nevada
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Nevada is a state in the Western, Mountain West, and Southwestern regions of the United States of America. Nevada is the 7th most extensive, the 34th most populous, nearly three-quarters of Nevadas people live in Clark County, which contains the Las Vegas–Paradise metropolitan area where three of the states four largest incorporated cities are located. Nevada is officially known as the Silver State because of the importance of silver to its history and economy. It is also known as the Battle Born State, because it achieved statehood during the Civil War, as the Sage-brush State, for the plant of the same name. Nevada borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, Nevada is largely desert and semi-arid, much of it located within the Great Basin. Areas south of the Great Basin are located within the Mojave Desert, while Lake Tahoe, about 86% of the states land is managed by various jurisdictions of the U. S. federal government, both civilian and military. Before European contact, Native Americans of the Paiute, Shoshone, the first Europeans to explore the region were Spanish. They called the region Nevada because of the snow covered the mountains in winter. The area formed part of the Viceroyalty of New Spain, the United States annexed the area in 1848 after its victory in the Mexican–American War, and it was incorporated as part of Utah Territory in 1850. The discovery of silver at the Comstock Lode in 1859 led to a boom that became an impetus to the creation of Nevada Territory out of western Utah Territory in 1861. Nevada became the 36th state on October 31,1864, as the second of two added to the Union during the Civil War. Nevada has a reputation for its libertarian laws, in 1940, with a population of just over 110,000 people, Nevada was by far the least-populated state, with less than half the population of the next least-populated state. However, legalized gambling and lenient marriage and divorce laws transformed Nevada into a major tourist destination in the 20th century, Nevada is the only U. S. state where prostitution is legal, though it is illegal in Clark County, Washoe County and Carson City. The tourism industry remains Nevadas largest employer, with mining continuing as a sector of the economy. The name Nevada comes from the Spanish nevada, meaning snow-covered, most Nevadans pronounce the second syllable of their state name using the vowel of trap. Many from outside the Western United States pronounce it with the vowel of father, although the latter pronunciation is closer to the Spanish pronunciation, it is not the pronunciation preferred by most Nevadans. State Assemblyman Harry Mortenson proposed a bill to recognize the alternate pronunciation of Nevada, though the bill was not supported by most legislators, the Nevadan pronunciation is the de facto official one, since it is the one used by the state legislature. Nevada is almost entirely within the Basin and Range Province, and is broken up by many mountain ranges
39.
Earthquake
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An earthquake is the shaking of the surface of the Earth, resulting from the sudden release of energy in the Earths lithosphere that creates seismic waves. Earthquakes can range in size from those that are so weak that they cannot be felt to those violent enough to people around. The seismicity or seismic activity of an area refers to the frequency, type, Earthquakes are measured using measurements from seismometers. The moment magnitude is the most common scale on which earthquakes larger than approximately 5 are reported for the entire globe and these two scales are numerically similar over their range of validity. Magnitude 3 or lower earthquakes are mostly imperceptible or weak and magnitude 7 and over potentially cause damage over larger areas. The largest earthquakes in historic times have been of magnitude slightly over 9, intensity of shaking is measured on the modified Mercalli scale. The shallower an earthquake, the damage to structures it causes. At the Earths surface, earthquakes manifest themselves by shaking and sometimes displacement of the ground, when the epicenter of a large earthquake is located offshore, the seabed may be displaced sufficiently to cause a tsunami. Earthquakes can also trigger landslides, and occasionally volcanic activity, in its most general sense, the word earthquake is used to describe any seismic event — whether natural or caused by humans — that generates seismic waves. Earthquakes are caused mostly by rupture of faults, but also by other events such as volcanic activity, landslides, mine blasts. An earthquakes point of rupture is called its focus or hypocenter. The epicenter is the point at ground level directly above the hypocenter, tectonic earthquakes occur anywhere in the earth where there is sufficient stored elastic strain energy to drive fracture propagation along a fault plane. The sides of a fault move past each other smoothly and aseismically only if there are no irregularities or asperities along the surface that increase the frictional resistance. Most fault surfaces do have such asperities and this leads to a form of stick-slip behavior, once the fault has locked, continued relative motion between the plates leads to increasing stress and therefore, stored strain energy in the volume around the fault surface. This continues until the stress has risen sufficiently to break through the asperity, suddenly allowing sliding over the portion of the fault. This energy is released as a combination of radiated elastic strain seismic waves, frictional heating of the fault surface and this process of gradual build-up of strain and stress punctuated by occasional sudden earthquake failure is referred to as the elastic-rebound theory. It is estimated that only 10 percent or less of a total energy is radiated as seismic energy. Most of the energy is used to power the earthquake fracture growth or is converted into heat generated by friction
40.
Swimming pool
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A swimming pool, swimming bath, wading pool, or paddling pool is a structure designed to hold water to enable swimming or other leisure activities. Pools can be built into the ground or built above ground, many health clubs, fitness centers and private clubs, such as the YMCA, have pools used mostly for exercise or recreation. Many towns and cities provide public pools, many hotels have pools available for their guests to use at their leisure. Educational facilities such as universities typically have pools for physical education classes, recreational activities, hot tubs and spas are pools filled with hot water, used for relaxation or hydrotherapy, and are common in homes, hotels, and health clubs. Special swimming pools are used for diving, specialized water sports, physical therapy as well as for the training of lifeguards. Swimming pools may be heated or unheated, the Great Bath at the site of Mohenjo-Daro in modern-day Pakistan was most likely the first swimming pool, dug during the 3rd millennium BC. This pool is 12 by 7 metres, is lined with bricks, ancient Greeks and Romans built artificial pools for athletic training in the palaestras, for nautical games and for military exercises. Roman emperors had private swimming pools in which fish were also kept, the first heated swimming pool was built by Gaius Maecenas of Rome in the 1st century BC. Gaius Maecenas was a rich Roman lord and considered one of the first patrons of arts, ancient Sinhalese built pairs of pools called Kuttam Pokuna in the kingdom of Anuradhapura, Sri Lanka in the 4th century BC. They were decorated with flights of steps, punkalas or pots of abundance, Swimming pools became popular in Britain in the mid-19th century. As early as 1837, six indoor pools with diving boards existed in London, the Maidstone Swimming Club in Maidstone, Kent is believed to be the oldest surviving swimming club in Britain. It was formed in 1844, in response to concerns over drownings in the River Medway, the club used to swim in the River Medway, and would hold races, diving competitions and water polo matches. The South East Gazette July 1844 reported an aquatic breakfast party, coffee, the coffee was kept hot over a fire, club members had to tread water and drink coffee at the same time. The last swimmers managed to overturn the raft, to the amusement of 150 spectators, the Amateur Swimming Association was founded in 1869 in England, and the Oxford Swimming Club in 1909. The presence of indoor baths in the area of Merton Street might have persuaded the less hardy of the aquatic brigade to join. So, bathers gradually became swimmers, and bathing pools became swimming pools, in 1939, Oxford created its first major public indoor pool at Temple Cowley. The modern Olympic Games started in 1896 and included swimming races, in the US, the Racquet Club of Philadelphia clubhouse boasts one of the worlds first modern above-ground swimming pools. The first swimming pool to go to sea on an ocean liner was installed on the White Star Lines Adriatic in 1907, the oldest known public swimming pool in America, Underwood Pool, is located in Belmont, Massachusetts
41.
1994 Northridge earthquake
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The 1994 Northridge earthquake occurred on January 17, at 4,30,55 a. m. PST and had its epicenter in Reseda, a neighborhood in the north-central San Fernando Valley region of Los Angeles and it had a duration of approximately 10–20 seconds. The peak ground velocity at the Rinaldi Receiving Station was 183 cm/s, in addition, two 6.0 Mw aftershocks occurred, the first about one minute after the initial event and the second approximately 11 hours later, the strongest of several thousand aftershocks in all. The death toll was 57, with more than 8,700 injured, in addition, property damage was estimated to be between $13 and $40 billion, making it one of the costliest natural disasters in U. S. history. The earthquake struck in the San Fernando Valley about 20 miles northwest of downtown Los Angeles, although given the name Northridge, the epicenter was located in the community of Reseda, it took several days to pinpoint the epicenter in detail. This was the first instance with a hypocenter directly beneath a U. S. city since the 1933 Long Beach earthquake, the National Geophysical Data Center placed the hypocenters geographical coordinates at 34°12′47″N 118°32′13″W and at a depth of 11.4 miles. It occurred on a previously undiscovered fault, now named the Northridge blind thrust fault, several other faults experienced minor rupture during the main shock and other ruptures occurred during large aftershocks, or triggered events. Damage occurred up to 85 miles away, with the most damage in the west San Fernando Valley, the exact number of fatalities is unknown, with sources estimating it at 60 or over 60, to 72, where most estimates fall around 60. The official death toll was placed at 57,33 people died immediately or within a few days from injuries sustained, some counts factor in related events such as a mans suicide possibly inspired by the loss of his business in the disaster. More than 8,700 were injured including 1,600 who required hospitalization, the Northridge Meadows apartment complex was one of the well-known affected areas in which sixteen people were killed as a result of the buildings collapse. The Northridge Fashion Center and California State University, Northridge also sustained very heavy damage—most notably, the earthquake also gained worldwide attention because of damage to the vast freeway network, which serves millions of commuters every day. Because of the morning darkness, he likely did not realize that the elevated roadway below him had collapsed. When the interchange was rebuilt one year later, it was renamed the Clarence Wayne Dean Memorial Interchange in his honor. Additional damage occurred about 50 miles southeast in Anaheim as the scoreboard at Anaheim Stadium collapsed onto several hundred seats, the stadium was vacant at the time. Although several commercial buildings also collapsed, loss of life was minimized because of the morning hour of the quake. Also, because of seismic activity in California, area building codes dictate that buildings incorporate structural design intended to withstand earthquakes. However, the damage caused revealed that some structural specifications did not perform as intended, because of these revelations, building codes were revised. Some structures were not red-tagged until months later, because damage was not immediately evident, the quake produced unusually strong ground accelerations in the range of 1.0 g
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1964 Alaska earthquake
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The 1964 Alaskan earthquake, also known as the Great Alaskan earthquake and Good Friday earthquake, occurred at 5,36 P. M. AST on Good Friday, March 27, across south-central Alaska, ground fissures, collapsing structures, and tsunamis resulting from the earthquake caused about 139 deaths. Lasting four minutes and thirty-eight seconds, the magnitude 9.2 megathrust earthquake was the most powerful recorded in North American history, soil liquefaction, fissures, landslides, and other ground failures caused major structural damage in several communities and much damage to property. Anchorage sustained great destruction or damage to many inadequately earthquake engineered houses, buildings, two hundred miles southwest, some areas near Kodiak were permanently raised by 30 feet. Nearby, a 27-foot tsunami destroyed the village of Chenega, killing 23 of the 68 people who lived there, survivors out-ran the wave, climbing to high ground. Post-quake tsunamis severely affected Whittier, Seward, Kodiak, and other Alaskan communities, as well as people and property in British Columbia, Washington, Oregon, tsunamis also caused damage in Hawaii and Japan. Evidence of motion directly related to the earthquake was reported from Florida. Alaska Standard Time, a fault between the Pacific and North American plates ruptured near College Fjord in Prince William Sound, the epicenter of the earthquake was 12.4 mi north of Prince William Sound,78 miles east of Anchorage and 40 miles west of Valdez. The focus occurred at a depth of approximately 15.5 mi, ocean floor shifts created large tsunamis, which resulted in many of the deaths and much of the property damage. Large rockslides were also caused, resulting in property damage. Vertical displacement of up to 38 feet occurred, affecting an area of 100,000 miles² within Alaska, studies of ground motion have led to a peak ground acceleration estimate of 0. 14–0.18 g. The Alaska earthquake was a subduction zone earthquake, caused by an oceanic plate sinking under a continental plate, the fault responsible was the Aleutian Megathrust, a reverse fault caused by a compressional force. This caused much of the ground which is the result of ground shifted to the opposite elevation. Two types of tsunamis were produced by subduction zone earthquake. There was a tectonic tsunami produced in addition to about 20 smaller and these smaller tsunami were produced by submarine and subaerial landslides and were responsible for the majority of the tsunami damage. Tsunami waves were noted in over 20 countries, including, Peru, New Zealand, Papua New Guinea, Japan, the largest tsunami wave was recorded in Shoup Bay, Alaska, with a height of about 220 ft. The quake was a reported XI on the modified Mercalli Intensity scale indicating major structural damage, property damage was estimated at about $311 million. Most damage occurred in Anchorage,75 mi northwest of the epicenter, the neighborhood lost 75 houses in the landslide, and the destroyed area has since been turned into Earthquake Park
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Alaska
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Alaska is a U. S. state located in the northwest extremity of North America. To the north are the Chukchi and Beaufort seas–the southern parts of the Arctic Ocean, the Pacific Ocean lies to the south and southwest. Alaska is the largest state in the United States by area, the 3rd least populous, approximately half of Alaskas residents live within the Anchorage metropolitan area. Alaskas economy is dominated by the fishing, natural gas, military bases and tourism are also a significant part of the economy. The United States purchased Alaska from the Russian Empire on March 30,1867, the area went through several administrative changes before becoming organized as a territory on May 11,1912. It was admitted as the 49th state of the U. S. on January 3,1959, the name Alaska was introduced in the Russian colonial period when it was used to refer to the peninsula. It was derived from an Aleut, or Unangam idiom, which refers to the mainland of Alaska. Literally, it means object to which the action of the sea is directed, Alaska is the northernmost and westernmost state in the United States and has the most easterly longitude in the United States because the Aleutian Islands extend into the Eastern Hemisphere. Alaska is the only non-contiguous U. S. state on continental North America and it is technically part of the continental U. S. but is sometimes not included in colloquial use, Alaska is not part of the contiguous U. S. often called the Lower 48. The capital city, Juneau, is situated on the mainland of the North American continent but is not connected by road to the rest of the North American highway system. Alaskas territorial waters touch Russias territorial waters in the Bering Strait, as the Russian Big Diomede Island, Alaska has a longer coastline than all the other U. S. states combined. Alaska is the largest state in the United States by total area at 663,268 square miles, over twice the size of Texas, Alaska is larger than all but 18 sovereign countries. Counting territorial waters, Alaska is larger than the area of the next three largest states, Texas, California, and Montana. It is also larger than the area of the 22 smallest U. S. states. Also referred to as the Panhandle or Inside Passage, this is the region of Alaska closest to the rest of the United States, as such, this was where most of the initial non-indigenous settlement occurred in the years following the Alaska Purchase. The region is dominated by the Alexander Archipelago as well as the Tongass National Forest and it contains the state capital Juneau, the former capital Sitka, and Ketchikan, at one time Alaskas largest city. The Alaska Marine Highway provides a vital transportation link throughout the area. The Interior is the largest region of Alaska, much of it is uninhabited wilderness, Fairbanks is the only large city in the region
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Puerto Rico
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Puerto Rico, officially the Commonwealth of Puerto Rico and briefly called Porto Rico, is an unincorporated territory of the United States located in the northeast Caribbean Sea. It is an archipelago that includes the island of Puerto Rico and a number of smaller ones such as Mona, Culebra. The capital and most populous city is San Juan and its official languages are Spanish and English, though Spanish predominates. The islands population is approximately 3.4 million, Puerto Ricos rich history, tropical climate, diverse natural scenery, renowned traditional cuisine, and attractive tax incentives make it a popular destination for travelers from around the world. Four centuries of Spanish colonial government transformed the ethnic, cultural and physical landscapes primarily with waves of African captives, and Canarian. In the Spanish imperial imagination, Puerto Rico played a secondary, in 1898, following the Spanish–American War, the United States appropriated Puerto Rico together with most former Spanish colonies under the terms of the Treaty of Paris. Puerto Ricans are natural-born citizens of the United States, however, Puerto Rico does not have a vote in the United States Congress, which governs the territory with full jurisdiction under the Puerto Rico Federal Relations Act of 1950. As a U. S. territory, American citizens residing on the island are disenfranchised at the level and may not vote for president. However, Congress approved a constitution, allowing U. S. citizens on the territory to elect a governor. A fifth referendum will be held in June 2017, with only Statehood, in early 2017, the Puerto Rican government-debt crisis posed serious problems for the government. The outstanding bond debt that had climbed to $70 billion or $12,000 per capita at a time with 12. 4% unemployment, the debt had been increasing during a decade long recession. Puerto Ricans often call the island Borinquen – a derivation of Borikén, its indigenous Taíno name, the terms boricua and borincano derive from Borikén and Borinquen respectively, and are commonly used to identify someone of Puerto Rican heritage. The island is also known in Spanish as la isla del encanto. Columbus named the island San Juan Bautista, in honor of Saint John the Baptist, eventually traders and other maritime visitors came to refer to the entire island as Puerto Rico, while San Juan became the name used for the main trading/shipping port and the capital city. The islands name was changed to Porto Rico by the United States after the Treaty of Paris of 1898, the anglicized name was used by the US government and private enterprises. The name was changed back to Puerto Rico by a joint resolution in Congress introduced by Félix Córdova Dávila in 1931, the ancient history of the archipelago known today as Puerto Rico is not well known. The scarce archaeological findings and early Spanish scholarly accounts from the colonial era constitute the basis of knowledge about them. The first comprehensive book on the history of Puerto Rico was written by Fray Íñigo Abbad y Lasierra in 1786, the first settlers were the Ortoiroid people, an Archaic Period culture of Amerindian hunters and fishermen who migrated from the South American mainland
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1755 Lisbon earthquake
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The 1755 Lisbon earthquake, also known as the Great Lisbon earthquake, occurred in the Kingdom of Portugal on Saturday,1 November, the holy day of All Saints Day, at around 09,40 local time. In combination with subsequent fires and a tsunami, the earthquake almost totally destroyed Lisbon, estimates place the death toll in Lisbon alone between 10,000 and 100,000 people, making it one of the deadliest earthquakes in history. The earthquake accentuated political tensions in the Kingdom of Portugal and profoundly disrupted the countrys colonial ambitions, the event was widely discussed and dwelt upon by European Enlightenment philosophers, and inspired major developments in theodicy. As the first earthquake studied scientifically for its effects over an area, it led to the birth of modern seismology. In 1755, the earthquake struck on the morning of 1 November, contemporary reports state that the earthquake lasted between three and a half and six minutes, causing fissures 5 metres wide to open in the city centre. Survivors rushed to the space of the docks for safety and watched as the water receded, revealing a sea floor littered with lost cargo. Approximately 40 minutes after the earthquake, a tsunami engulfed the harbour and downtown area, rushing up the Tagus river, were forced to gallop as fast as possible to the upper grounds for fear of being carried away. It was followed by two more waves, in the areas unaffected by the tsunami, fire quickly broke out, and flames raged for five days. Lisbon was not the only Portuguese city affected by the catastrophe, throughout the south of the country, in particular the Algarve, destruction was rampant. The tsunami destroyed some coastal fortresses in the Algarve and, in the lower levels, almost all the coastal towns and villages of the Algarve were heavily damaged, except Faro, which was protected by the sandy banks of Ria Formosa. In Lagos, the reached the top of the city walls. Other towns of different Portuguese regions, such as Peniche, Cascais, and even Covilhã, the shock waves of the earthquake destroyed part of Covilhãs castle walls and its large towers. On the island of Madeira, Funchal and many smaller settlements suffered significant damage, almost all of the ports in the Azores archipelago suffered most of their destruction from the tsunami, with the sea penetrating about 150 m inland. Shocks from the earthquake were felt throughout Europe as far as Finland and North Africa, and according to some even in Greenland. Tsunamis as tall as 20 metres swept the coast of North Africa, a three-metre tsunami hit Cornwall on the southern English coast. Galway, on the west coast of Ireland, was also hit, at Kinsale, several vessels were whirled round in the harbor, and water poured into the marketplace. In 2015, it was revealed that the waves may have reached the coast of Brazil. Such a hypothesis was raised by reviewing letters sent by Brazilian authorities at the time of the earthquake and these letters describe damage and destruction caused by gigantic waves
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Scotland
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Scotland is a country that is part of the United Kingdom and covers the northern third of the island of Great Britain. It shares a border with England to the south, and is surrounded by the Atlantic Ocean, with the North Sea to the east. In addition to the mainland, the country is made up of more than 790 islands, including the Northern Isles, the Kingdom of Scotland emerged as an independent sovereign state in the Early Middle Ages and continued to exist until 1707. By inheritance in 1603, James VI, King of Scots, became King of England and King of Ireland, Scotland subsequently entered into a political union with the Kingdom of England on 1 May 1707 to create the new Kingdom of Great Britain. The union also created a new Parliament of Great Britain, which succeeded both the Parliament of Scotland and the Parliament of England. Within Scotland, the monarchy of the United Kingdom has continued to use a variety of styles, titles, the legal system within Scotland has also remained separate from those of England and Wales and Northern Ireland, Scotland constitutes a distinct jurisdiction in both public and private law. Glasgow, Scotlands largest city, was one of the worlds leading industrial cities. Other major urban areas are Aberdeen and Dundee, Scottish waters consist of a large sector of the North Atlantic and the North Sea, containing the largest oil reserves in the European Union. This has given Aberdeen, the third-largest city in Scotland, the title of Europes oil capital, following a referendum in 1997, a Scottish Parliament was re-established, in the form of a devolved unicameral legislature comprising 129 members, having authority over many areas of domestic policy. Scotland is represented in the UK Parliament by 59 MPs and in the European Parliament by 6 MEPs, Scotland is also a member nation of the British–Irish Council, and the British–Irish Parliamentary Assembly. Scotland comes from Scoti, the Latin name for the Gaels, the Late Latin word Scotia was initially used to refer to Ireland. By the 11th century at the latest, Scotia was being used to refer to Scotland north of the River Forth, alongside Albania or Albany, the use of the words Scots and Scotland to encompass all of what is now Scotland became common in the Late Middle Ages. Repeated glaciations, which covered the land mass of modern Scotland. It is believed the first post-glacial groups of hunter-gatherers arrived in Scotland around 12,800 years ago, the groups of settlers began building the first known permanent houses on Scottish soil around 9,500 years ago, and the first villages around 6,000 years ago. The well-preserved village of Skara Brae on the mainland of Orkney dates from this period and it contains the remains of an early Bronze Age ruler laid out on white quartz pebbles and birch bark. It was also discovered for the first time that early Bronze Age people placed flowers in their graves, in the winter of 1850, a severe storm hit Scotland, causing widespread damage and over 200 deaths. In the Bay of Skaill, the storm stripped the earth from a large irregular knoll, when the storm cleared, local villagers found the outline of a village, consisting of a number of small houses without roofs. William Watt of Skaill, the laird, began an amateur excavation of the site, but after uncovering four houses
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Canal
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Canals and navigations are human-made channels for water conveyance, or to service water transport vehicles. In the vernacular, both are referred to as canals, and in most cases, the works will have a series of dams. These areas are referred to as water levels, often just called levels. In contrast, a canal cuts across a drainage divide atop a ridge, many canals have been built at elevations towering over valleys and others water ways crossing far below. Cities need a lot of water and many canals with sources of water at a higher level can deliver water to a destination where there is a lack of water. The Roman Empires Aqueducts were such water supply canals, a navigation is a series of channels that run roughly parallel to the valley and stream bed of an unimproved river. A navigation always shares the drainage basin of the river, a vessel uses the calm parts of the river itself as well as improvements, traversing the same changes in height. A true canal is a channel that cuts across a drainage divide, most commercially important canals of the first half of the 19th century were a little of each, using rivers in long stretches, and divide crossing canals in others. This is true for many canals still in use, there are two broad types of canal, Waterways, canals and navigations used for carrying vessels transporting goods and people. These can be subdivided into two kinds, Those connecting existing lakes, rivers, other canals or seas and oceans and those connected in a city network, such as the Canal Grande and others of Venice Italy, the gracht of Amsterdam, and the waterways of Bangkok. Aqueducts, water canals that are used for the conveyance and delivery of potable water for human consumption, municipal uses, hydro power canals. Historically canals were of importance to commerce and the development, growth. In 1855 the Lehigh Canal carried over 1.2 million tons of burning anthracite coal, by the 1930s the company which built. By the early 1880s, canals which had little ability to compete with rail transport, were off the map. In the next couple of decades, coal was diminished as the heating fuel of choice by oil. Later, after World War I when motor-trucks came into their own, Canals are built in one of three ways, or a combination of the three, depending on available water and available path, Human made streams A canal can be created where no stream presently exists. Either the body of the canal is dug or the sides of the canal are created by making dykes or levees by piling dirt, stone, the water for the canal must be provided from an external source, like streams or reservoirs. Where the new waterway must change elevation engineering works like locks, lifts or elevators are constructed to raise, examples include canals that connect valleys over a higher body of land, like Canal du Midi, Canal de Briare and the Panama Canal
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Sweden
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Sweden, officially the Kingdom of Sweden, is a Scandinavian country in Northern Europe. It borders Norway to the west and Finland to the east, at 450,295 square kilometres, Sweden is the third-largest country in the European Union by area, with a total population of 10.0 million. Sweden consequently has a low density of 22 inhabitants per square kilometre. Approximately 85% of the lives in urban areas. Germanic peoples have inhabited Sweden since prehistoric times, emerging into history as the Geats/Götar and Swedes/Svear, Southern Sweden is predominantly agricultural, while the north is heavily forested. Sweden is part of the area of Fennoscandia. The climate is in very mild for its northerly latitude due to significant maritime influence. Today, Sweden is a monarchy and parliamentary democracy, with a monarch as head of state. The capital city is Stockholm, which is also the most populous city in the country, legislative power is vested in the 349-member unicameral Riksdag. Executive power is exercised by the government chaired by the prime minister, Sweden is a unitary state, currently divided into 21 counties and 290 municipalities. Sweden emerged as an independent and unified country during the Middle Ages, in the 17th century, it expanded its territories to form the Swedish Empire, which became one of the great powers of Europe until the early 18th century. Swedish territories outside the Scandinavian Peninsula were gradually lost during the 18th and 19th centuries, the last war in which Sweden was directly involved was in 1814, when Norway was militarily forced into personal union. Since then, Sweden has been at peace, maintaining a policy of neutrality in foreign affairs. The union with Norway was peacefully dissolved in 1905, leading to Swedens current borders, though Sweden was formally neutral through both world wars, Sweden engaged in humanitarian efforts, such as taking in refugees from German-occupied Europe. After the end of the Cold War, Sweden joined the European Union on 1 January 1995 and it is also a member of the United Nations, the Nordic Council, Council of Europe, the World Trade Organization and the Organisation for Economic Co-operation and Development. Sweden maintains a Nordic social welfare system that provides health care. The modern name Sweden is derived through back-formation from Old English Swēoþēod and this word is derived from Sweon/Sweonas. The Swedish name Sverige literally means Realm of the Swedes, excluding the Geats in Götaland, the etymology of Swedes, and thus Sweden, is generally not agreed upon but may derive from Proto-Germanic Swihoniz meaning ones own, referring to ones own Germanic tribe
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. Science News. Society for Science and the Public.
"Seiche". Encyclopædia Britannica. 24 (11th ed.). 1911.
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