Windward and leeward
Windward is the direction upwind from the point of reference. Leeward is the direction downwind from the point of reference, the side of a ship that is towards the leeward is its lee side. If the vessel is heeling under the pressure of the wind, during the age of sail, the term weather was used as a synonym for windward in some contexts, as in the weather gage. Windward and leeward directions are important factors to consider when sailing a sailing ship, other terms with broadly the same meaning are widely used, particularly upwind and downwind. The windward vessel is normally the more maneuverable vessel, for this reason, rule 12 of the International Regulations for Preventing Collisions at Sea stipulates that the windward vessel gives way to the leeward vessel. The opposing warship to leeward could often do little but comply without exposing itself unduly and this was particularly important once artillery was introduced to naval warfare. The ships heeled away from the wind so that the vessel was exposing part of her bottom to shot.
Leeward and windward refer respectively to what a game stalker would call downwind and upwind, the terms are used by seamen in relation to their ships but in reference to islands in an archipelago and to the different sides of a single island. In the latter case, the side is that side of an island subject to the prevailing wind. The leeward side is the side protected by the elevation of the island from the prevailing wind, leeward or windward siting is an important weather and climate factor on oceanic islands. In the case of an archipelago, windward islands are upwind and leeward islands are the downwind ones
A tributary or affluent is a stream or river that flows into a larger stream or main stem river or a lake. A tributary does not flow directly into a sea or ocean and the main stem river drain the surrounding drainage basin of its surface water and groundwater, leading the water out into an ocean. A confluence, where two or more bodies of water together, usually refers to the joining of tributaries. The opposite to a tributary is a distributary, a river or stream that branches off from, distributaries are most often found in river deltas. Right tributary and left tributary are terms stating the orientation of the relative to the flow of the main stem river. These terms are defined from the perspective of looking downstream, where tributaries have the same name as the river into which they feed, they are called forks. These are typically designated by compass direction, for example, the American River receives flow from its North and South forks. The Chicago Rivers North Branch has the East and Middle Fork, the South Branch has its South Fork, forks are sometimes designated as right or left.
Here, the handedness is from the point of view of an observer facing upstream, for instance, Steer Creek has a left tributary which is called Right Fork Steer Creek. Tributaries are sometimes listed starting with those nearest to the source of the river, the Strahler Stream Order examines the arrangement of tributaries in a hierarchy of first, second and higher orders, with the first-order tributary being typically the least in size. For example, a second-order tributary would be the result of two or more first-order tributaries combining to form the second-order tributary, another method is to list tributaries from mouth to source, in the form of a tree structure, stored as a tree data structure
Mount Waiʻaleʻale, often spelled Waialeale in English without the ʻokina, is a shield volcano and the second highest point on the island of Kauaʻi in the Hawaiian Islands. Recent reports though mention that over the period 1978–2007 the wettest spot in Hawaii is Big Bog on Maui, the summit of Waiʻaleʻale features a tropical rainforest climate, with substantial rainfall throughout the course of the year. Similarly, The Weather Network and the Guinness Book of Weather Records quote 335 days with rain here while suggests that rain falls on 360 days per year. The local tourist industry of Waialeale has promoted it as the wettest spot, although the 38-year average at Mawsynram, both Mawsynram and Cherrapunji in Meghalaya are recognized by the Guinness Book of World Records as having higher average rainfall. Mawsynrams rainfall is concentrated in the season, while the rain at Waiʻaleʻale is more evenly distributed through the year. It has a round and regular conical shape, exposing all sides of its peak to winds.
Its peak lies just below the so-called trade wind inversion layer of 6,000 feet, the great rainfall in the area produces the Alakaʻi Wilderness Preserve, a large boggy area that is home to many rare plants. The ground is so wet that although trails exist, access by foot to the Waiʻaleʻale area is extremely difficult, a number of rare local plant species are named for this mountain, including Astelia waialealae, Melicope waialealae, and the endemic Dubautia waialealae. Honolulu Star-Bulletin article on Waiʻaleʻale Site with hiking info on routes to Waialeale and Kawaikini, real-time rainfall data from the USGS Waiʻaleʻale Raingauge
Computer simulations reproduce the behavior of a system using a model. Simulation of a system is represented as the running of the systems model and it can be used to explore and gain new insights into new technology and to estimate the performance of systems too complex for analytical solutions. The scale of events being simulated by computer simulations has far exceeded anything possible using traditional paper-and-pencil mathematical modeling, other examples include a 1-billion-atom model of material deformation, a 2. Because of the computational cost of simulation, computer experiments are used to perform such as uncertainty quantification. A computer model is the algorithms and equations used to capture the behavior of the system being modeled, by contrast, computer simulation is the actual running of the program that contains these equations or algorithms. Simulation, therefore, is the process of running a model, thus one would not build a simulation, one would build a model, and either run the model or equivalently run a simulation.
It was a simulation of 12 hard spheres using a Monte Carlo algorithm, Computer simulation is often used as an adjunct to, or substitute for, modeling systems for which simple closed form analytic solutions are not possible. The external data requirements of simulations and models vary widely, for some, the input might be just a few numbers, while others might require terabytes of information. Because of this variety, and because diverse simulation systems have common elements. Systems that accept data from external sources must be careful in knowing what they are receiving. While it is easy for computers to read in values from text or binary files, often they are expressed as error bars, a minimum and maximum deviation from the value range within which the true value lie. Even small errors in the data can accumulate into substantial error in the simulation. While all computer analysis is subject to the GIGO restriction, this is true of digital simulation. Indeed, observation of this inherent, cumulative error in digital systems was the main catalyst for the development of chaos theory, another way of categorizing models is to look at the underlying data structures.
For time-stepped simulations, there are two classes, Simulations which store their data in regular grids and require only next-neighbor access are called stencil codes. Many CFD applications belong to this category, if the underlying graph is not a regular grid, the model may belong to the meshfree method class. Equations define the relationships between elements of the system and attempt to find a state in which the system is in equilibrium. Such models are used in simulating physical systems, as a simpler modeling case before dynamic simulation is attempted
A mountain is a large landform that stretches above the surrounding land in a limited area, usually in the form of a peak. A mountain is steeper than a hill. Mountains are formed through tectonic forces or volcanism and these forces can locally raise the surface of the earth. Mountains erode slowly through the action of rivers, weather conditions, a few mountains are isolated summits, but most occur in huge mountain ranges. High elevations on mountains produce colder climates than at sea level and these colder climates strongly affect the ecosystems of mountains, different elevations have different plants and animals. Because of the less hospitable terrain and climate, mountains tend to be used less for agriculture and more for resource extraction and recreation, the highest mountain on Earth is Mount Everest in the Himalayas of Asia, whose summit is 8,850 m above mean sea level. The highest known mountain on any planet in the Solar System is Olympus Mons on Mars at 21,171 m, there is no universally accepted definition of a mountain.
Elevation, relief, steepness and continuity have been used as criteria for defining a mountain, whether a landform is called a mountain may depend on local usage. The highest point in San Francisco, California, is called Mount Davidson, notwithstanding its height of 300 m, Mount Scott outside Lawton, Oklahoma is only 251 m from its base to its highest point. Whittows Dictionary of Physical Geography states Some authorities regard eminences above 600 metres as mountains, in addition, some definitions include a topographical prominence requirement, typically 100 or 500 feet. For a while, the US defined a mountain as being 1,000 feet or taller, any similar landform lower than this height was considered a hill. However, the United States Geological Survey concludes that these terms do not have technical definitions in the US, using these definitions, mountains cover 33% of Eurasia, 19% of South America, 24% of North America, and 14% of Africa. As a whole, 24% of the Earths land mass is mountainous, there are three main types of mountains, volcanic and block.
All three types are formed from plate tectonics, when portions of the Earths crust move, compressional forces, isostatic uplift and intrusion of igneous matter forces surface rock upward, creating a landform higher than the surrounding features. The height of the feature makes it either a hill or, if higher and steeper, major mountains tend to occur in long linear arcs, indicating tectonic plate boundaries and activity. Volcanoes are formed when a plate is pushed below another plate, at a depth of around 100 km, melting occurs in rock above the slab, and forms magma that reaches the surface. When the magma reaches the surface, it builds a volcanic mountain. Examples of volcanoes include Mount Fuji in Japan and Mount Pinatubo in the Philippines, the magma does not have to reach the surface in order to create a mountain, magma that solidifies below ground can still form dome mountains, such as Navajo Mountain in the US
Prince Pyotr Alexeyevich Kropotkin was a Russian activist and philosopher, who advocated anarchism. Born into an aristocratic land-owning family, he attended a school and served as an officer in Siberia. He was imprisoned for his activism in 1874 and managed to escape two years and he spent the next 41 years in exile in Switzerland, France and in England. He returned to Russia after the Russian Revolution in 1917 but was disappointed by the Bolshevik form of state socialism, Kropotkin was a proponent of a decentralised communist society free from central government and based on voluntary associations of self-governing communities and worker-run enterprises. He contributed the article on anarchism to the Encyclopædia Britannica Eleventh Edition, Kropotkin was born in Moscow, into the second-highest level of the Russian aristocracy. His mother was the daughter of a Cossack general and his father, Alexei Petrovich Kropotkin, was a prince in Smolensk, of the Rurik dynasty which had ruled Russia before the rise of the Romanovs.
Kropotkins father owned large tracts of land and nearly 1,200 male serfs in three provinces, nder the influence of republican teachings, Kropotkin dropped his princely title at age 12, and even rebuked his friends, when they so referred to him. In 1857, at age 14, Kropotkin enrolled in the Corps of Pages at St. Petersburg, Kropotkins memoirs detail the hazing and other abuse of pages for which the Corps had become notorious. In Moscow, Kropotkin developed an interest in the condition of the peasantry, although his work as a page for Tsar Alexander II made Kropotkin skeptical about the tsars liberal reputation, Kropotkin was greatly pleased by the tsars decision to emancipate the serfs in 1861. In St. Petersburg, he read widely on his own account, in 1862, Kropotkin was promoted from the Corps of Pages to the army. The members of the corps had the right to choose the regiment to which they would be attached. For some time, he was aide de camp to the governor of Transbaikalia at Chita, he was appointed attaché for Cossack affairs to the governor-general of East Siberia at Irkutsk.
The expeditions yielded valuable geographical results, in 1866, Kropotkin began reading the works of the French anarchist Pierre-Joseph Proudhon, and other political thinkers such as John Stuart Mill and Alexander Herzen. These readings, along with his experiences among peasants in Siberia and his departure from a family tradition of military service prompted his father to disinherit him, leaving him a prince with no visible means of support. In 1871, he explored the glacial deposits of Finland and Sweden for the Society, accordingly, he refused the offer and returned to St. Petersburg, where he joined the revolutionary party. Kropotkin visited Switzerland in 1872 and became a member of the International Workingmens Association at Geneva, however, he found that he did not like IWAs style of socialism. Instead, he studied the programme of the more radical Jura federation at Neuchâtel and spent time in the company of the leading members, on returning to Russia, Kropotkins friend Dmitri Klements introduced him to the Circle of Tchaikovsky, a socialist/populist group created in 1872.
Kropotkin worked to spread propaganda among peasants and workers
The Pennines /ˈpɛnaɪnz/, known as the Pennine Chain or Pennine Hills, are a range of mountains and hills in Northern England separating North West England from Yorkshire and North East England. The Pennines are an important water catchment area with numerous reservoirs in the streams of the river valleys. The region is considered to be one of the most scenic areas of the United Kingdom. The North Pennines and Nidderdale are designated Areas of Outstanding Natural Beauty, as are Bowland, parts of the Pennines are incorporated into the Peak District National Park, the Yorkshire Dales National Park and the Northumberland National Park. Britains oldest long-distance footpath, the Pennine Way, runs along most of the Pennine Chain and is 268 miles long, various etymologies have been proposed treating Pennine as though it were a native Brittonic/Modern Welsh name related to pen-. He found that the derivation from Bertram was widely believed and considered uncomfortable, in fact, he found repeated comparisons going back at least as early as Camden, many of whose placenames and ideas Bertram incorporated into his work.
Bertram was responsible with popularizing the name against other such as Daniel Defoes English Andes. His own form of the name was the Pennine Alps, which today is used for a section of the continental Alps. Those mountains derive their name from the Latin Alpes Pœninæ, the St Bernard Pass whose name has been derived from the Carthaginians, a local god. This was the used in the invasions of Italy by the Gallic Boii. Various towns and geographical features within the Pennines retain Celtic names, including Penrith, the fell Pen-y-ghent, the River Eden, more commonly, local names result from Anglo-Saxon and Norse settlements. In Yorkshire and Cumbria, many words of Norse origin, not commonly used in standard English, are part of speech, for example, gill/ghyll, fell. This is located within parts of Cumbria, southern parts of Northumberland. This is within parts of Yorkshire and eastern parts of Derbyshire with foothills continuing into western parts of Nottinghamshire. This is within the Stoke-on-Trent conurbation of northern Staffordshire and the parts of Derbyshire above the city of Derby.
Apart from the uplands in the Lake District fringes, other Cumbrian Fells, the Pennines have been carved from a series of geological structures whose overall form is a broad anticline whose axis extends in a north–south direction. The North Pennines are coincident with the Alston Block, whilst the Yorkshire Dales are coincident with the Askrigg Block, in the south the Peak District is essentially a flat-topped dome. Each of these consists of Carboniferous limestone overlain with Millstone Grit
Leeds /liːdz/ is a city in West Yorkshire, England. Historically in Yorkshires West Riding, the history of Leeds can be traced to the 5th century when the name referred to an area of the Kingdom of Elmet. The name has applied to many administrative entities over the centuries. It changed from being the appellation of a small borough in the 13th century, through several incarnations. In the 17th and 18th centuries Leeds became a centre for the production. During the Industrial Revolution, Leeds developed into a mill town, wool was the dominant industry but flax, iron foundries, printing. From being a market town in the valley of the River Aire in the 16th century Leeds expanded and absorbed the surrounding villages to become a populous urban centre by the mid-20th century. The city has the third largest jobs total by local authority area with 480,000 in employment and self-employment at the beginning of 2015. Leeds is ranked as a world city by the Globalization and World Cities Research Network.
Leeds is served by four universities, and has the fourth largest student population in the country and has the fourth largest urban economy. After London, Leeds is the largest legal and financial centre in the UK, with over 30 national and international banks located in the city. Leeds is the UKs third largest manufacturing centre with around 1,800 firms and 39,000 employees, the largest sub-sectors are engineering and publishing, food and drink and medical technology. Outside of London, Leeds has the third busiest railway station, Public transport and road communications networks in the region are focused on Leeds and there are a number of twinning arrangements with towns and cities in other countries. The name Leeds derives from the old Brythonic word Ladenses meaning people of the fast-flowing river and this name originally referred to the forested area covering most of the Brythonic kingdom of Elmet, which existed during the 5th century into the early 7th century. An inhabitant of Leeds is locally known as a Loiner, a word of uncertain origin, the term Leodensian is used, from the citys Latin name.
Leeds developed as a town in the Middle Ages as part of the local agricultural economy. Before the Industrial Revolution it became a centre for the manufacture of woollen cloth. Leeds handled one sixth of Englands export trade in 1770, initially in textiles, was accelerated by the building of the Aire and Calder Navigation in 1699 and the Leeds and Liverpool Canal in 1816
General circulation model
A general circulation model is a type of climate model. It employs a model of the general circulation of a planetary atmosphere or ocean. It uses the Navier–Stokes equations on a sphere with thermodynamic terms for various energy sources. These equations are the basis for computer programs used to simulate the Earths atmosphere or oceans and oceanic GCMs are key components along with sea ice and land-surface components. GCMs and global models are used for weather forecasting, understanding the climate. Versions designed for decade to century time scale climate applications were created by Syukuro Manabe and Kirk Bryan at the Geophysical Fluid Dynamics Laboratory in Princeton. These models are based on the integration of a variety of fluid dynamical, the acronym GCM originally stood for General Circulation Model. Recently, a second meaning came into use, namely Global Climate Model, while these do not refer to the same thing, General Circulation Models are typically the tools used for modelling climate, and hence the two terms are sometimes used interchangeably.
In 1956, Norman Phillips developed a model that could realistically depict monthly. It became the first successful climate model, following Phillipss work, several groups began working to create GCMs. The first to combine both oceanic and atmospheric processes was developed in the late 1960s at the NOAA Geophysical Fluid Dynamics Laboratory, by the early 1980s, the United States National Center for Atmospheric Research had developed the Community Atmosphere Model, this model has been continuously refined. In 1996, efforts began to model soil and vegetation types, the Hadley Centre for Climate Prediction and Researchs HadCM3 model coupled ocean-atmosphere elements. The role of gravity waves was added in the mid-1980s, gravity waves are required to simulate regional and global scale circulations accurately. Atmospheric and oceanic GCMs can be coupled to form a coupled general circulation model. With the addition of such as a sea ice model or a model for evapotranspiration over land. Thus a carbon CTM may allow a GCM to better predict anthropogenic changes in carbon dioxide concentrations, in addition, this approach allows accounting for inter-system feedback, e. g. chemistry-climate models allow the possible effects of climate change on ozone hole to be studied.
Climate prediction uncertainties depend on uncertainties in chemical and social models, significant uncertainties and unknowns remain, especially regarding the future course of human population and technology. Three-dimensional GCMs apply discrete equations for fluid motion and integrate these forward in time and they contain parameterisations for processes such as convection that occur on scales too small to be resolved directly
Siberia is an extensive geographical region, and by the broadest definition is known as North Asia. Siberia has historically been a part of Russia since the 17th century, the territory of Siberia extends eastwards from the Ural Mountains to the watershed between the Pacific and Arctic drainage basins. It stretches southwards from the Arctic Ocean to the hills of north-central Kazakhstan and to the borders of Mongolia. With an area of 13.1 million square kilometres, Siberia accounts for 77% of Russias land area and this is equivalent to an average population density of about 3 inhabitants per square kilometre, making Siberia one of the most sparsely populated regions on Earth. If it were a country by itself, it would still be the largest country in area, the origin of the name is unknown. Some sources say that Siberia originates from the Siberian Tatar word for sleeping land, another account sees the name as the ancient tribal ethnonym of the Sirtya, a folk, which spoke a language that evolved into the Ugric languages.
This ethnic group was assimilated to the Siberian Tatar people. The modern usage of the name was recorded in the Russian language after the Empires conquest of the Siberian Khanate, a further variant claims that the region was named after the Xibe people. The Polish historian Chycliczkowski has proposed that the name derives from the word for north. He said that the neighbouring Chinese and Mongolians would not have known Russian and he suggests that the name is a combination of two words, su and bir. The region is of significance, as it contains bodies of prehistoric animals from the Pleistocene Epoch. Specimens of Goldfuss cave lion cubs and another woolly mammoth from Oymyakon, a rhinoceros from the Kolyma River. The Siberian Traps were formed by one of the largest known volcanic events of the last 500 million years of Earths geological history. They continued for a million years and are considered a cause of the Great Dying about 250 million years ago. At least three species of human lived in Southern Siberia around 40,000 years ago, H. sapiens, H. neanderthalensis, the last was determined in 2010, by DNA evidence, to be a new species.
Siberia was inhabited by different groups of such as the Enets, the Nenets, the Huns, the Scythians. The Khan of Sibir in the vicinity of modern Tobolsk was known as a prominent figure who endorsed Kubrat as Khagan of Old Great Bulgaria in 630, the Mongols conquered a large part of this area early in the 13th century. With the breakup of the Golden Horde, the autonomous Khanate of Sibir was established in the late 15th century, turkic-speaking Yakut migrated north from the Lake Baikal region under pressure from the Mongol tribes during the 13th to 15th century
Meteorology is a branch of the atmospheric sciences which includes atmospheric chemistry and atmospheric physics, with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did not occur until the 18th century, the 19th century saw modest progress in the field after weather observation networks were formed across broad regions. Prior attempts at prediction of weather depended on historical data, Meteorological phenomena are observable weather events that are explained by the science of meteorology. Different spatial scales are used to describe and predict weather on local, Meteorology, atmospheric physics, and atmospheric chemistry are sub-disciplines of the atmospheric sciences. Meteorology and hydrology compose the interdisciplinary field of hydrometeorology, the interactions between Earths atmosphere and its oceans are part of a coupled ocean-atmosphere system. Meteorology has application in diverse fields such as the military, energy production, agriculture.
The word meteorology is from Greek μετέωρος metéōros lofty, high and -λογία -logia -logy, varāhamihiras classical work Brihatsamhita, written about 500 AD, provides clear evidence that a deep knowledge of atmospheric processes existed even in those times. In 350 BC, Aristotle wrote Meteorology, Aristotle is considered the founder of meteorology. One of the most impressive achievements described in the Meteorology is the description of what is now known as the hydrologic cycle and they are all called swooping bolts because they swoop down upon the Earth. Lightning is sometimes smoky, and is called smoldering lightning, sometimes it darts quickly along, at other times, it travels in crooked lines, and is called forked lightning. When it swoops down upon some object it is called swooping lightning, the Greek scientist Theophrastus compiled a book on weather forecasting, called the Book of Signs. The work of Theophrastus remained a dominant influence in the study of weather, in 25 AD, Pomponius Mela, a geographer for the Roman Empire, formalized the climatic zone system.
According to Toufic Fahd, around the 9th century, Al-Dinawari wrote the Kitab al-Nabat, ptolemy wrote on the atmospheric refraction of light in the context of astronomical observations. St. Roger Bacon was the first to calculate the size of the rainbow. He stated that a rainbow summit can not appear higher than 42 degrees above the horizon, in the late 13th century and early 14th century, Kamāl al-Dīn al-Fārisī and Theodoric of Freiberg were the first to give the correct explanations for the primary rainbow phenomenon. Theoderic went further and explained the secondary rainbow, in 1716, Edmund Halley suggested that aurorae are caused by magnetic effluvia moving along the Earths magnetic field lines. In 1441, King Sejongs son, Prince Munjong, invented the first standardized rain gauge and these were sent throughout the Joseon Dynasty of Korea as an official tool to assess land taxes based upon a farmers potential harvest. In 1450, Leone Battista Alberti developed a swinging-plate anemometer, and was known as the first anemometer, in 1607, Galileo Galilei constructed a thermoscope
Trade winds transport African dust westward across the Atlantic Ocean into the Caribbean Sea, as well as portions of southeastern North America. Shallow cumulus clouds are seen within trade wind regimes, and are capped from becoming taller by a trade wind inversion, the weaker the trade winds become, the more rainfall can be expected in the neighboring landmasses. The term trade winds originally derives from the fourteenth century late Middle English word trade. The Portuguese recognized the importance of the winds in navigation in both the north and south Atlantic ocean as early as the 15th century. From West Africa, the Portuguese had to sail away from continental Portugal and they could turn northeast, to the area around the Azores islands, and finally east to mainland Europe. They learned that to reach South Africa, they needed to go far out in the ocean, head for Brazil, following the African coast southbound means upwind in the Southern hemisphere. In the Pacific ocean, the wind circulation, which included both the trade wind easterlies and higher-latitude Westerlies, was unknown to Europeans until Andres de Urdanetas voyage in 1565.
The captain of a sailing ship seeks a course along which the winds can be expected to blow in the direction of travel, for example, Manila galleons could not sail into the wind at all. Between 1847 and 1849, Matthew Fontaine Maury collected enough information to create wind, as part of the Hadley cell circulation, surface air flows toward the equator while the flow aloft is towards the poles. A low-pressure area of calm, light winds near the equator is known as the doldrums, near-equatorial trough, intertropical front. When located within a region, this zone of low pressure. Around 30° in both hemispheres, air begins to descend toward the surface in subtropical high-pressure belts known as subtropical ridges. The subsident air is dry because as it descends, the temperature increases, but the absolute humidity remains constant. This warm, dry air is known as an air mass. An increase of temperature with height is known as a temperature inversion, when it occurs within a trade wind regime, it is known as a trade wind inversion.
The surface air flows from these subtropical high-pressure belts toward the Equator is deflected toward the west in both hemispheres by the Coriolis effect. These winds blow predominantly from the northeast in the Northern Hemisphere, the trade winds of both hemispheres meet at the doldrums. As they blow across tropical regions, air masses heat up over lower latitudes due to direct sunlight