1. Energy – In physics, energy is the property that must be transferred to an object in order to perform work on – or to heat – the object, and can be converted in form, but not created or destroyed. The SI unit of energy is the joule, which is the transferred to an object by the mechanical work of moving it a distance of 1 metre against a force of 1 newton. Mass and energy are closely related, for example, with a sensitive enough scale, one could measure an increase in mass after heating an object. Living organisms require available energy to stay alive, such as the humans get from food. Civilisation gets the energy it needs from energy resources such as fuels, nuclear fuel. The processes of Earths climate and ecosystem are driven by the radiant energy Earth receives from the sun, the total energy of a system can be subdivided and classified in various ways. It may also be convenient to distinguish gravitational energy, thermal energy, several types of energy, electric energy. Many of these overlap, for instance, thermal energy usually consists partly of kinetic. Some types of energy are a mix of both potential and kinetic energy. An example is energy which is the sum of kinetic. Whenever physical scientists discover that a phenomenon appears to violate the law of energy conservation. Heat and work are special cases in that they are not properties of systems, in general we cannot measure how much heat or work are present in an object, but rather only how much energy is transferred among objects in certain ways during the occurrence of a given process. Heat and work are measured as positive or negative depending on which side of the transfer we view them from, the distinctions between different kinds of energy is not always clear-cut. In contrast to the definition, energeia was a qualitative philosophical concept, broad enough to include ideas such as happiness. The modern analog of this property, kinetic energy, differs from vis viva only by a factor of two, in 1807, Thomas Young was possibly the first to use the term energy instead of vis viva, in its modern sense. Gustave-Gaspard Coriolis described kinetic energy in 1829 in its modern sense, the law of conservation of energy was also first postulated in the early 19th century, and applies to any isolated system. It was argued for years whether heat was a physical substance, dubbed the caloric, or merely a physical quantity. In 1845 James Prescott Joule discovered the link between mechanical work and the generation of heat and these developments led to the theory of conservation of energy, formalized largely by William Thomson as the field of thermodynamicsEnergy – In a typical lightning strike, 500 megajoules of electric potential energy is converted into the same amount of energy in other forms, mostly light energy, sound energy and thermal energy.
2. Physics – Physics is the natural science that involves the study of matter and its motion and behavior through space and time, along with related concepts such as energy and force. One of the most fundamental disciplines, the main goal of physics is to understand how the universe behaves. Physics is one of the oldest academic disciplines, perhaps the oldest through its inclusion of astronomy, Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the mechanisms of other sciences while opening new avenues of research in areas such as mathematics. Physics also makes significant contributions through advances in new technologies that arise from theoretical breakthroughs, the United Nations named 2005 the World Year of Physics. Astronomy is the oldest of the natural sciences, the stars and planets were often a target of worship, believed to represent their gods. While the explanations for these phenomena were often unscientific and lacking in evidence, according to Asger Aaboe, the origins of Western astronomy can be found in Mesopotamia, and all Western efforts in the exact sciences are descended from late Babylonian astronomy. The most notable innovations were in the field of optics and vision, which came from the works of many scientists like Ibn Sahl, Al-Kindi, Ibn al-Haytham, Al-Farisi and Avicenna. The most notable work was The Book of Optics, written by Ibn Al-Haitham, in which he was not only the first to disprove the ancient Greek idea about vision, but also came up with a new theory. In the book, he was also the first to study the phenomenon of the pinhole camera, many later European scholars and fellow polymaths, from Robert Grosseteste and Leonardo da Vinci to René Descartes, Johannes Kepler and Isaac Newton, were in his debt. Indeed, the influence of Ibn al-Haythams Optics ranks alongside that of Newtons work of the same title, the translation of The Book of Optics had a huge impact on Europe. From it, later European scholars were able to build the devices as what Ibn al-Haytham did. From this, such important things as eyeglasses, magnifying glasses, telescopes, Physics became a separate science when early modern Europeans used experimental and quantitative methods to discover what are now considered to be the laws of physics. Newton also developed calculus, the study of change, which provided new mathematical methods for solving physical problems. The discovery of new laws in thermodynamics, chemistry, and electromagnetics resulted from greater research efforts during the Industrial Revolution as energy needs increased, however, inaccuracies in classical mechanics for very small objects and very high velocities led to the development of modern physics in the 20th century. Modern physics began in the early 20th century with the work of Max Planck in quantum theory, both of these theories came about due to inaccuracies in classical mechanics in certain situations. Quantum mechanics would come to be pioneered by Werner Heisenberg, Erwin Schrödinger, from this early work, and work in related fields, the Standard Model of particle physics was derived. Areas of mathematics in general are important to this field, such as the study of probabilities, in many ways, physics stems from ancient Greek philosophyPhysics – Further information: Outline of physics
3. Thermodynamics – Thermodynamics is a branch of physics concerned with heat and temperature and their relation to energy and work. The behavior of these quantities is governed by the four laws of thermodynamics, the laws of thermodynamics are explained in terms of microscopic constituents by statistical mechanics. Thermodynamics applies to a variety of topics in science and engineering, especially physical chemistry, chemical engineering. The initial application of thermodynamics to mechanical heat engines was extended early on to the study of chemical compounds, Chemical thermodynamics studies the nature of the role of entropy in the process of chemical reactions and has provided the bulk of expansion and knowledge of the field. Other formulations of thermodynamics emerged in the following decades, statistical thermodynamics, or statistical mechanics, concerned itself with statistical predictions of the collective motion of particles from their microscopic behavior. In 1909, Constantin Carathéodory presented a mathematical approach to the field in his axiomatic formulation of thermodynamics. A description of any thermodynamic system employs the four laws of thermodynamics that form an axiomatic basis, the first law specifies that energy can be exchanged between physical systems as heat and work. In thermodynamics, interactions between large ensembles of objects are studied and categorized, central to this are the concepts of the thermodynamic system and its surroundings. A system is composed of particles, whose average motions define its properties, properties can be combined to express internal energy and thermodynamic potentials, which are useful for determining conditions for equilibrium and spontaneous processes. With these tools, thermodynamics can be used to describe how systems respond to changes in their environment and this can be applied to a wide variety of topics in science and engineering, such as engines, phase transitions, chemical reactions, transport phenomena, and even black holes. This article is focused mainly on classical thermodynamics which primarily studies systems in thermodynamic equilibrium, non-equilibrium thermodynamics is often treated as an extension of the classical treatment, but statistical mechanics has brought many advances to that field. Guericke was driven to make a vacuum in order to disprove Aristotles long-held supposition that nature abhors a vacuum. Shortly after Guericke, the English physicist and chemist Robert Boyle had learned of Guerickes designs and, in 1656, in coordination with English scientist Robert Hooke, using this pump, Boyle and Hooke noticed a correlation between pressure, temperature, and volume. In time, Boyles Law was formulated, which states that pressure, later designs implemented a steam release valve that kept the machine from exploding. By watching the valve rhythmically move up and down, Papin conceived of the idea of a piston and he did not, however, follow through with his design. Nevertheless, in 1697, based on Papins designs, engineer Thomas Savery built the first engine, although these early engines were crude and inefficient, they attracted the attention of the leading scientists of the time. Black and Watt performed experiments together, but it was Watt who conceived the idea of the condenser which resulted in a large increase in steam engine efficiency. Drawing on all the work led Sadi Carnot, the father of thermodynamics, to publish Reflections on the Motive Power of FireThermodynamics – Annotated color version of the original 1824 Carnot heat engine showing the hot body (boiler), working body (system, steam), and cold body (water), the letters labeled according to the stopping points in Carnot cycle
4. Energy development – Energy development is a field of endeavor focused on making available sufficient primary energy sources and secondary energy forms to meet the needs of society. These endeavors encompass those which provide for the production of conventional, alternative and renewable sources of energy, Energy conservation and efficiency measures reduce the effect of energy development, and can have benefits to society with changes in economic cost and with changes in the environmental issues. Contemporary industrial societies use primary and secondary sources for transportation. Also, large populations have various generation and delivery services for energy distribution. This energy is used by people who can afford the cost to live under various climatic conditions through the use of heating, ventilation, and/or air conditioning. Level of use of energy sources differs across societies, along with the convenience, levels of traffic congestion, pollution sources. Thousands of people in society are employed in the energy industry, the conventional industry comprises the petroleum industry the gas industry, the electrical power industry the coal industry, and the nuclear power industry. New energy industries include the energy industry, comprising alternative and sustainable manufacture, distribution. Illustrative of this can be the emanations from the sun, which with its nuclear fusion is the most important energy source for the Earth and which provides its energy in the form of radiation. The natural elements of the world exist in forms that can be converted into usable energy and are resources from which society can obtain energy to produce heat, light. According to their nature, the plants can be classified into, Primary, They are found in nature, wind, water, solar, wood, coal, oil. Secondary, Are those obtained from primary sources, electricity. The principle stated by Antoine Lavoisier on the conservation of matter applies to energy development, thus any energy production is actually a recovery transformation of the forms of energy whose origin is that of the universe. This material itself constitutes a form of energy, called mass energy, fossil fuel sources burn coal or hydrocarbon fuels, which are the remains of the decomposition of plants and animals. There are three types of fossil fuels, coal, petroleum, and natural gas. Another fossil fuel, liquefied gas, is principally derived from the production of natural gas. Heat from burning fuel is used either directly for space heating and process heating, or converted to mechanical energy for vehicles, industrial processes. Fossil energy is from recovered fossils and are originated in degradated products of dead plants and these fossil fuels are based on the carbon cycle and thus allow stored energy to be recycled todayEnergy development – The Moss Landing Power Plant in California is a fossil-fuel power station that burns natural gas in a turbine to produce electricity.
5. Peak oil – Peak oil, an event based on M. King Hubberts theory, is the point in time when the maximum rate of extraction of petroleum is reached, after which it is expected to enter terminal decline. Peak oil theory is based on the rise, peak, fall. It is often confused with oil depletion, however, peak oil is the point of extraction, while depletion refers to a period of falling reserves. Some observers, such as petroleum industry experts Kenneth S. Predictions vary greatly as to exactly these negative effects would be. Oil extraction forecasts on which predictions of peak oil are based are made within a range which includes optimistic and pessimistic scenarios. Pessimistic predictions of future oil extraction made after 2007 stated either that the peak had already occurred, that oil extraction was on the cusp of the peak, or that it would occur shortly. Hubberts original prediction that US peak oil would be in about 1970 seemed accurate for a time, in addition, Hubberts original predictions for world peak oil extraction proved premature. The idea that the rate of oil extraction would peak and irreversibly decline is an old one, in 1919, David White, chief geologist of the United States Geological Survey, wrote of US petroleum. The peak of extraction will soon be passed, possibly within 3 years, in 1953, Eugene Ayers, a researcher for Gulf Oil, projected that if US ultimate recoverable oil reserves were 100 billion barrels, then extraction in the US would peak no later than 1960. If ultimate recoverable were to be as high as 200 billion barrels, likewise for the world, he projected a peak somewhere between 1985 and 2000. Ayers made his projections without a mathematical model, King Hubbert used statistical modelling in 1956 to accurately predict that United States oil extraction would peak between 1965 and 1971. Hubbert used a semi-logistical curved model and he assumed the extraction rate of a limited resource would follow a roughly symmetrical distribution. Depending on the limits of exploitability and market pressures, the rise or decline of resource extraction over time might be sharper or more stable, appear more linear or curved. That model and its variants are now called Hubbert peak theory, they have used to describe and predict the peak and decline of extraction from regions, countries. The same theory has also applied to other limited-resource extraction. In a 2006 analysis of Hubbert theory, it was noted that uncertainty in real world oil extraction amounts, by comparing the fit of various other models, it was found that Hubberts methods yielded the closest fit over all, but that none of the models were very accurate. In 1956 Hubbert himself recommended using a family of possible extraction curves when predicting a extraction peak, more recently, the term peak oil was popularized by Colin Campbell and Kjell Aleklett in 2002 when they helped form the Association for the Study of Peak Oil and Gas. In his publications, Hubbert used the term peak extraction rate, Global demand for crude oil grew an average of 1. 76% per year from 1994 to 2006, with a high growth of 3. 4% in 2003–2004Peak oil – Global oil discoveries peaked in the 1960s.
6. Energy conservation – Energy conservation refers to the reducing of energy consumption through using less of an energy service. Energy conservation differs from efficient energy use, which refers to using less energy for a constant service, driving less is an example of energy conservation. Driving the same amount with a higher mileage vehicle is an example of energy efficiency, Energy conservation and efficiency are both energy reduction techniques. Energy conservation is a part of the concept of sufficiency, even though energy conservation reduces energy services, it can result in increased environmental quality, national security, personal financial security and higher savings. It is at the top of the energy hierarchy. It also lowers energy costs by preventing future resource depletion, some countries employ energy or carbon taxes to motivate energy users to reduce their consumption. Carbon taxes can allow consumption to shift to power and other alternatives that carry a different set of environmental side effects. Meanwhile, taxes on all energy consumption stand to reduce energy use across the board, the State of California employs a tiered energy tax whereby every consumer receives a baseline energy allowance that carries a low tax. As usage increases above that baseline, the tax is increasing drastically, such programs aim to protect poorer households while creating a larger tax burden for high energy consumers. One of the ways to improve energy conservation in buildings is to use an energy audit. This is normally accomplished by trained professionals and can be part of some of the programs discussed above. In addition, recent development of smartphone apps enable homeowners to complete relatively sophisticated energy audits themselves, building technologies and smart meters can allow energy users, business and residential, to see graphically the impact their energy use can have in their workplace or homes. Advanced real-time energy metering is able to help save energy by their actions. In passive solar building design, windows, walls, and floors are made to collect, store and this is called passive solar design or climatic design because, unlike active solar heating systems, it doesnt involve the use of mechanical and electrical devices. The key to designing a passive building is to best take advantage of the local climate. Elements to be considered include window placement and glazing type, thermal insulation, thermal mass, passive solar design techniques can be applied most easily to new buildings, but existing buildings can be retrofitted. In the United States, suburban infrastructure evolved during an age of easy access to fossil fuels. Zoning reforms that allow greater urban density as well as designs for walking and bicycling can greatly reduce energy consumed for transportation, consumers are often poorly informed of the savings of energy efficient productsEnergy conservation – An assortment of energy-efficient semiconductor (LED) lamps for commercial and residential lighting use. LED lamps use at least 75% less energy, and last 25 times longer, than traditional incandescent light bulbs.
7. Energy (technology) – For people, energy is an overwhelming need and as a scarce resource it has been an underlying cause of political conflicts and wars. The gathering and use of resources can be harmful to local ecosystems. As an interdisciplinary science Energy technology is linked with many fields in sundry. Physics, for thermodynamics and nuclear physics Chemistry for fuel, combustion, air pollution, flue gas, battery technology, electrical engineering Engineering, often for fluid energy machines such as combustion engines, turbines, pumps and compressors. Geography, for energy and exploration for resources. Mining, for petrochemical and fossil fuels, agriculture and forestry, for sources of renewable energy. Meteorology for wind and solar energy, environmental studies, for studying the effect of energy use and production on the environment, nature and climate change. Infrastructure involves substations and transformer stations, power lines and electrical cable, load management and power management over networks have meaningful sway on overall energy efficiency. Electric heating is widely used and researched. Thermodynamics deals with the laws of energy conversion and is drawn from theoretical Physics. Thermal and chemical energy are intertwined with chemistry and environmental studies, combustion has to do with burners and chemical engines of all kinds, grates and incinerators along with their energy efficiency, pollution and operational safety. Exhaust gas purification technology aims to air pollution through sundry mechanical, thermal and chemical cleaning methods. Emission control technology is a field of process and chemical engineering, boiler technology deals with the design, construction and operation of steam boilers and turbines, drawn from applied mechanics and materials engineering. Energy conversion has to do with internal combustion engines, turbines, pumps, fans and so on, high thermal and mechanical loads bring about operational safety worries which are dealt with through many branches of applied engineering science. Nuclear power generation has been controversial in many countries for several decades. There are high hopes that fusion technologies will one day replace most fission reactors, photovoltaic power draws electricity from solar radiation through solar cells, either locally or in large photovoltaic power plants and uses semiconductor technology. Solar heating uses solar panels which gather heat from sunlight to heat buildings, Solar thermal power produces electricity by converting solar heat. Wind turbines draw energy from atmospheric currents and are designed using aerodynamics along with knowledge taken from mechanical and electrical engineering, where it can be had, geothermal energy is used for heating and electricityEnergy (technology) – The Sun provides solar energy for the Earth
8. Efficient energy use – Efficient energy use, sometimes simply called energy efficiency, is the goal to reduce the amount of energy required to provide products and services. For example, insulating a home allows a building to use less heating and cooling energy to achieve, installing fluorescent lights, LED lights or natural skylights reduces the amount of energy required to attain the same level of illumination compared with using traditional incandescent light bulbs. Improvements in energy efficiency are generally achieved by adopting an efficient technology or production process or by application of commonly accepted methods to reduce energy losses. There are many motivations to improve energy efficiency, reducing energy use reduces energy costs and may result in a financial cost saving to consumers if the energy savings offset any additional costs of implementing an energy efficient technology. Reducing energy use is seen as a solution to the problem of reducing greenhouse gas emissions. Energy efficiency and renewable energy are said to be the pillars of sustainable energy policy and are high priorities in the sustainable energy hierarchy. Energy efficiency has proved to be a strategy for building economies without necessarily increasing energy consumption. For example, the state of California began implementing energy-efficiency measures in the mid-1970s, including building code, during the following years, Californias energy consumption has remained approximately flat on a per capita basis while national US consumption doubled. In general, up to 75% of the electricity used in the US today could be saved with efficiency measures that cost less than the electricity itself. The same holds true for this is home and there is 78% of electricity uses D in your home-owners, in fact, researchers at the US Department of Energy and their consortium, Residential Energy Efficient Distribution Systems have found that duct efficiency may be as low as 50–70%. The US Department of Energy has stated there is potential for energy saving in the magnitude of 90 Billion kWh by increasing home energy efficiency. Other studies have emphasized this.2 percent average growth anticipated through 2020 in a business-as-usual scenario, international standards ISO17743 and ISO17742 provide a documented methodology for calculating and reporting on energy savings and energy efficiency for countries and cities. Modern appliances, such as, freezers, ovens, stoves, dishwashers, installing a clothesline will significantly reduce ones energy consumption as their dryer will be used less. Current energy efficient refrigerators, for example, use 40 percent less energy than conventional models did in 2001, in the US, the corresponding figures would be 17 billion kWh of electricity and 27,000,000,000 lb CO2. According to a 2009 study from McKinsey & Company the replacement of old appliances is one of the most efficient global measures to reduce emissions of greenhouse gases. Modern power management systems also reduce energy usage by idle appliances by turning them off or putting them into a low-energy mode after a certain time, many countries identify energy-efficient appliances using energy input labeling. The impact of energy efficiency on peak demand depends on when the appliance is used, for example, an air conditioner uses more energy during the afternoon when it is hot. Therefore, an efficient air conditioner will have a larger impact on peak demand than off-peak demandEfficient energy use – A spiral-type integrated compact fluorescent lamp, which has been in popular use among North American consumers since its introduction in the mid-1990s.
9. Energy security – Energy security is the association between national security and the availability of natural resources for energy consumption. Access to cheap energy has become essential to the functioning of modern economies, however, the uneven distribution of energy supplies among countries has led to significant vulnerabilities. Rapid deployment of energy and energy efficiency, and technological diversification of energy sources, would result in significant energy security. The modern world relies on a vast energy supply to fuel everything from transportation to communication, to security, Energy plays an important role in the national security of any given country as a fuel to power the economic engine. Some sectors rely on more heavily than others, for example. Foreign oil supplies are vulnerable to disruptions from in-state conflict, exporters interests. The political and economic instability caused by war or other such as strike action can also prevent the proper functioning of the energy industry in a supplier country. For example, the nationalization of oil in Venezuela has triggered strikes, exporters may have political or economic incentive to limit their foreign sales or cause disruptions in the supply chain. Since Venezuelas nationalization of oil, anti-American Hugo Chávez threatened to cut off supplies to the United States more than once. The 1973 oil embargo against the United States is an example in which oil supplies were cut off to the United States due to U. S. support of Israel during the Yom Kippur War. This has been done to apply pressure during economic negotiations—such as during the 2007 Russia–Belarus energy dispute, terrorist attacks targeting oil facilities, pipelines, tankers, refineries, and oil fields are so common they are referred to as industry risks. Infrastructure for producing the resource is extremely vulnerable to sabotage, one of the worst risks to oil transportation is the exposure of the five ocean chokepoints, like the Iranian-controlled Strait of Hormuz. Although still a minority concern, the possibility of price rises resulting from the peaking of oil production is also starting to attract the attention of at least the French government. Increased competition over resources may also lead to the formation of security compacts to enable an equitable distribution of oil. However, this may happen at the expense of less developed economies. The Group of Five, precursors to the G8, first met in 1975 to coordinate economic and energy policies in the wake of the 1973 Arab oil embargo, a rise in inflation and a global economic slowdown. NATO leaders meeting in Bucharest Romania, in April 2008, may discuss the possibility of using the alliance as an instrument of energy security. One of the possibilities include placing troops in the Caucasus region to police oil and it can also involve entering into international agreements to underpin international energy trading relationships, such as the Energy Charter Treaty in EuropeEnergy security – A U.S. Navy F/A-18 Super Hornet displaying an "Energy Security" logo.
10. Effects of global warming – The effects of global warming are the environmental and social changes caused by human emissions of greenhouse gases. There is a consensus that climate change is occurring. Many impacts of change have already been observed, including glacier retreat, changes in the timing of seasonal events. Future effects of change will vary depending on climate change policies. The two main policies to address climate change are reducing human greenhouse gas emissions and adapting to the impacts of climate change, near-term climate change policies could significantly affect long-term climate change impacts. Stringent mitigation policies might be able to limit warming to around 2 °C or below. Without mitigation, increased demand and extensive use of fossil fuels might lead to global warming of around 4 °C. Higher magnitudes of warming would be more difficult to adapt to. In this article, climate change means a change in climate that persists over a period of time. The World Meteorological Organization defines this time period as 30 years, examples of climate change include increases in global surface temperature, changes in rainfall patterns, and changes in the frequency of extreme weather events. Changes in climate may be due to causes, e. g. changes in the suns output, or due to human activities. Also, the term anthropogenic forcing refers to the influence exerted on a habitat or chemical environment by humans and this article breaks down some of the impacts of climate change according to different levels of future global warming. This way of describing impacts has, for instance, been used in the IPCC Assessment Reports on climate change, the instrumental temperature record shows global warming of around 0.6 °C during the 20th century. The future level of warming is uncertain, but a wide range of estimates have been made. The IPCCs SRES scenarios have been used to make projections of future climate change. The SRES scenarios are baseline scenarios, which means that they do not take into account any current or future measures to limit GHG emissions, emissions projections of the SRES scenarios are broadly comparable in range to the baseline emissions scenarios that have been developed by the scientific community. In the IPCC Fourth Assessment Report, changes in global mean temperature were projected using the six SRES marker emissions scenarios. Emissions projections for the six SRES marker scenarios are representative of the set of forty SRES scenariosEffects of global warming – A map that shows ice concentration on 16 September 2012, along with the extent of the previous record low (yellow line) and the mid-September median extent (black line) setting a new record low that was 18 percent smaller than the previous record and nearly 50 percent smaller than the long-term (1979-2000) average.
11. Global warming – Global warming and climate change are terms for the observed century-scale rise in the average temperature of the Earths climate system and its related effects. Multiple lines of evidence show that the climate system is warming. The largest human influence has been emission of gases such as carbon dioxide, methane. These findings have been recognized by the science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing. Future climate change and associated impacts will differ from region to region around the globe, anticipated effects include warming global temperature, rising sea levels, changing precipitation, and expansion of deserts in the subtropics. Warming is expected to be greater over land than over the oceans and greatest in the Arctic, with the retreat of glaciers, permafrost. Effects significant to humans include the threat to security from decreasing crop yields. Possible societal responses to global warming include mitigation by emissions reduction, adaptation to its effects, building systems resilient to its effects, most countries are parties to the United Nations Framework Convention on Climate Change, whose ultimate objective is to prevent dangerous anthropogenic climate change. Public reactions to global warming and concern about its effects are also increasing, a global 2015 Pew Research Center report showed a median of 54% consider it a very serious problem. There are significant regional differences, with Americans and Chinese among the least concerned, the global average surface temperature shows a warming of 0.85 °C in the period 1880 to 2012, based on multiple independently produced datasets. Earths average surface temperature rose by 0. 74±0.18 °C over the period 1906–2005, the rate of warming almost doubled for the last half of that period. The rest has melted ice and warmed the continents and atmosphere, the average temperature of the lower troposphere has increased between 0.12 and 0.135 °C per decade since 1979, according to satellite temperature measurements. The warming that is evident in the temperature record is consistent with a wide range of observations. The probability that these changes could have occurred by chance is virtually zero, temperature changes vary over the globe. Since 1979, land temperatures have increased about twice as fast as ocean temperatures, ocean temperatures increase more slowly than land temperatures because of the larger effective heat capacity of the oceans and because the ocean loses more heat by evaporation. Since the beginning of industrialisation the temperature difference between the hemispheres has increased due to melting of sea ice and snow in the North. Average arctic temperatures have been increasing at almost twice the rate of the rest of the world in the past 100 years, the thermal inertia of the oceans and slow responses of other indirect effects mean that climate can take centuries or longer to adjust to changes in forcing. Some of this warming will be driven by past natural forcings which are still seeking equilibrium in the climate systemGlobal warming – Atmospheric CO 2 concentration from 650,000 years ago to near present, using ice core proxy data and direct measurements.
12. Greenhouse gases – A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the cause of the greenhouse effect. The primary greenhouse gases in Earths atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, without greenhouse gases, the average temperature of Earths surface would be about −18 °C, rather than the present average of 15 °C. In the Solar System, the atmospheres of Venus, Mars, human activities since the beginning of the Industrial Revolution have produced a 40% increase in the atmospheric concentration of carbon dioxide, from 280 ppm in 1750 to 400 ppm in 2015. This increase has occurred despite the uptake of a portion of the emissions by various natural sinks involved in the carbon cycle. Anthropogenic carbon dioxide emissions come from combustion of fuels, principally coal, oil. Greenhouse gases are those that absorb and emit infrared radiation in the range emitted by Earth. The proportion of an emission remaining in the atmosphere after a time is the airborne fraction. The annual airborne fraction is the ratio of the increase in a given year to that years total emissions. Over the last 50 years the annual airborne fraction for CO2 has been increasing at 0.25 ±0. 21%/year, therefore, they do not contribute significantly to the greenhouse effect and usually are omitted when discussing greenhouse gases. Some gases have indirect radiative effects and this happens in two main ways. One way is that when they break down in the atmosphere they produce another greenhouse gas, for example, methane and carbon monoxide are oxidized to give carbon dioxide. Oxidation of CO to CO2 directly produces an increase in radiative forcing although the reason is subtle. The peak of the thermal IR emission from Earths surface is close to a strong vibrational absorption band of CO2. On the other hand, the single CO vibrational band only absorbs IR at much higher frequencies, where the ~300 K thermal emission of the surface is at least a factor of ten lower. Oxidation of methane to CO2, which requires reactions with the OH radical, produces a reduction, since CO2 is a weaker greenhouse gas than methane. As described below this is not the story, since the oxidations of CO. In any case, the calculation of the radiative effect needs to include both the direct and indirect forcingGreenhouse gases – The false colors in this image represent concentrations of carbon monoxide in the lower atmosphere, ranging from about 390 parts per billion (dark brown pixels), to 220 parts per billion (red pixels), to 50 parts per billion (blue pixels).
13. Natural science – Natural science is a branch of science concerned with the description, prediction, and understanding of natural phenomena, based on observational and empirical evidence. Mechanisms such as review and repeatability of findings are used to try to ensure the validity of scientific advances. Natural science can be divided into two branches, life science and physical science. Physical science is subdivided into branches, including physics, space science, chemistry and these branches of natural science may be further divided into more specialized branches. Modern natural science succeeded more classical approaches to natural philosophy, usually traced to ancient Greece, galileo, Descartes, Francis Bacon, and Newton debated the benefits of using approaches which were more mathematical and more experimental in a methodical way. Still, philosophical perspectives, conjectures, and presuppositions, often overlooked, systematic data collection, including discovery science, succeeded natural history, which emerged in the 16th century by describing and classifying plants, animals, minerals, and so on. Today, natural history suggests observational descriptions aimed at popular audiences, philosophers of science have suggested a number of criteria, including Karl Poppers controversial falsifiability criterion, to help them differentiate scientific endeavors from non-scientific ones. Validity, accuracy, and quality control, such as peer review and this field encompasses a set of disciplines that examines phenomena related to living organisms. The scale of study can range from sub-component biophysics up to complex ecologies, biology is concerned with the characteristics, classification and behaviors of organisms, as well as how species were formed and their interactions with each other and the environment. The biological fields of botany, zoology, and medicine date back to periods of civilization. However, it was not until the 19th century that became a unified science. Once scientists discovered commonalities between all living things, it was decided they were best studied as a whole, modern biology is divided into subdisciplines by the type of organism and by the scale being studied. Molecular biology is the study of the chemistry of life, while cellular biology is the examination of the cell. At a higher level, anatomy and physiology looks at the internal structures, constituting the scientific study of matter at the atomic and molecular scale, chemistry deals primarily with collections of atoms, such as gases, molecules, crystals, and metals. The composition, statistical properties, transformations and reactions of these materials are studied, chemistry also involves understanding the properties and interactions of individual atoms and molecules for use in larger-scale applications. Most chemical processes can be studied directly in a laboratory, using a series of techniques for manipulating materials, chemistry is often called the central science because of its role in connecting the other natural sciences. Early experiments in chemistry had their roots in the system of Alchemy, the science of chemistry began to develop with the work of Robert Boyle, the discoverer of gas, and Antoine Lavoisier, who developed the theory of the Conservation of mass. The success of science led to a complementary chemical industry that now plays a significant role in the world economyNatural science – The natural sciences seek to understand how the world and universe around us works. There are five major branches: Chemistry (center), astronomy, earth science, physics, and biology (clockwise from top-left).
14. Thermal energy – In thermodynamics, thermal energy refers to the internal energy present in a system due to its temperature. Heat is energy transferred spontaneously from a hotter to a system or body. Heat is energy in transfer, not a property of the system, on the other hand, internal energy is a property of a system. The internal energy of a gas can in this sense be regarded as thermal energy. In this case, however, thermal energy and internal energy are identical, systems that are more complex than ideal gases can undergo phase transitions. Phase transitions can change the energy of the system without changing its temperature. Therefore, the thermal energy cannot be defined solely by the temperature, for these reasons, the concept of the thermal energy of a system is ill-defined and is not used in thermodynamics. In an 1847 lecture entitled On Matter, Living Force, and Heat, James Prescott Joule characterized various terms that are related to thermal energy. He identified the terms latent heat and sensible heat as forms of heat each effecting distinct physical phenomena, namely the potential and kinetic energy of particles, Heat transfer Ocean thermal energy conversion Thermal science Example of incorrect use of heat and thermal energyThermal energy – Thermal radiation in visible light can be seen on this hot metalwork. Thermal energy would ideally be the amount of heat required to warm the metal to its temperature, but this quantity is not well-defined, as there are many ways to obtain a given body at a given temperature, and each of them may require a different amount of total heat input. Thermal energy, unlike internal energy, is therefore not a state function.
15. Electrical energy – Electrical energy is the energy newly derived from electric potential energy or kinetic energy. When loosely used to describe energy absorbed or delivered by an electrical circuit electrical energy talks about energy which has converted from electric potential energy. This energy is supplied by the combination of current and electric potential that is delivered by the circuit. At the point that this potential energy has been converted to another type of energy. Thus, all energy is potential energy before it is delivered to the end-use. Once converted from potential energy, electrical energy can always be called another type of energy, electric generation is The fundamental principle of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday. His basic method is used today, electricity is generated by the movement of a loop of wire. For electric utilities, it is the first step in the delivery of electricity to consumers, the other processes, electricity transmission, distribution, and electrical power storage and recovery using pumped-storage methods are normally carried out by the electric power industry. There are many technologies that can be and are used to generate electricity such as solar photovoltaicsElectrical energy – Turbo generators provide the majority of the world's electrical energy
16. Radiant energy – In physics, and in particular as measured by radiometry, radiant energy is the energy of electromagnetic and gravitational radiation. As energy, its SI unit is the joule, the quantity of radiant energy may be calculated by integrating radiant flux with respect to time. The symbol Qe is often used throughout literature to denote radiant energy, in branches of physics other than radiometry, electromagnetic energy is referred to using E or W. The term is used particularly when electromagnetic radiation is emitted by a source into the surrounding environment and this radiation may be visible or invisible to the human eye. The term radiant energy is most commonly used in the fields of radiometry, solar energy, heating and lighting, in modern applications involving transmission of power from one location to another, radiant energy is sometimes used to refer to the electromagnetic waves themselves, rather than their energy. In the past, the term electro-radiant energy has also been used, the term radiant energy also applies to gravitational radiation. For example, the first gravitational waves ever observed were produced by a black hole collision that emitted about 5. 3×1047 joules of gravitational-wave energy. Because electromagnetic radiation can be conceptualized as a stream of photons, alternatively, EM radiation can be viewed as an electromagnetic wave, which carries energy in its oscillating electric and magnetic fields. These two views are completely equivalent and are reconciled to one another in quantum field theory, EM radiation can have various frequencies. The bands of frequency present in a given EM signal may be defined, as is seen in atomic spectra, or may be broad. In the photon picture, the energy carried by each photon is proportional to its frequency, in the wave picture, the energy of a monochromatic wave is proportional to its intensity. This implies that if two EM waves have the intensity, but different frequencies, the one with the higher frequency contains fewer photons. When EM waves are absorbed by an object, the energy of the waves is converted to heat and this is a very familiar effect, since sunlight warms surfaces that it irradiates. Often this phenomenon is associated particularly with infrared radiation, but any kind of radiation will warm an object that absorbs it. EM waves can also be reflected or scattered, in case their energy is redirected or redistributed as well. Radiant energy is one of the mechanisms by which energy can enter or leave an open system, such a system can be man-made, such as a solar energy collector, or natural, such as the Earths atmosphere. In geophysics, most atmospheric gases, including the greenhouse gases, allow the Suns short-wavelength radiant energy to pass through to the Earths surface, heating the ground and oceans. The absorbed solar energy is partly re-emitted as longer wavelength radiation, radiant energy is produced in the sun as a result of nuclear fusionRadiant energy – Visible light, such as sunlight carries radiant energy, which is used in solar power generation.
17. Nuclear power – Nuclear power is the use of nuclear reactions that release nuclear energy to generate heat, which most frequently is then used in steam turbines to produce electricity in a nuclear power plant. The term includes nuclear fission, nuclear decay and nuclear fusion, since all electricity supplying technologies use cement, etc. during construction, emissions are yet to be brought to zero. Each result is contrasted with coal and fossil gas at 820 and 490 g CO2 eq/kWh, there is a social debate about nuclear power. Proponents, such as the World Nuclear Association and Environmentalists for Nuclear Energy, contend that nuclear power is a safe, opponents, such as Greenpeace International and NIRS, contend that nuclear power poses many threats to people and the environment. These include the Chernobyl disaster which occurred in 1986, the Fukushima Daiichi nuclear disaster, there have also been some nuclear submarine accidents. Energy production from coal, petroleum, natural gas and hydroelectricity has caused a number of fatalities per unit of energy generated due to air pollution. In 2015, Ten new reactors were connected to the grid, seven reactors were permanently shut down. 441 reactors had a net capacity of 382,855 megawatts of electricity. 67 new nuclear reactors were under construction, Most of the new activity is in China where there is an urgent need to control pollution from coal plants. In October 2016, Watts Bar 2 became the first new United States reactor to enter commercial operation since 1996. The same year, his doctoral student James Chadwick discovered the neutron, further work by Enrico Fermi in the 1930s focused on using slow neutrons to increase the effectiveness of induced radioactivity. Experiments bombarding uranium with neutrons led Fermi to believe he had created a new, transuranic element and they determined that the relatively tiny neutron split the nucleus of the massive uranium atoms into two roughly equal pieces, contradicting Fermi. Numerous scientists, including Leó Szilárd, who was one of the first, recognized that if fission reactions released additional neutrons, a self-sustaining nuclear chain reaction could result. In the United States, where Fermi and Szilárd had both emigrated, this led to the creation of the first man-made reactor, known as Chicago Pile-1, which achieved criticality on December 2,1942. In 1945, the pocketbook The Atomic Age heralded the untapped atomic power in everyday objects and depicted a future where fossil fuels would go unused. One science writer, David Dietz, wrote that instead of filling the gas tank of a car two or three times a week, people travel for a year on a pellet of atomic energy the size of a vitamin pill. The United Kingdom, Canada, and the USSR proceeded over the course of the late 1940s, electricity was generated for the first time by a nuclear reactor on December 20,1951, at the EBR-I experimental station near Arco, Idaho, which initially produced about 100 kW. Work was also researched in the US on nuclear marine propulsionNuclear power – The 1200 MWe, Leibstadt fission-electric power station in Switzerland. The boiling water reactor (BWR), located inside the dome capped cylindrical structure, is dwarfed in size by its cooling tower. The station produces a yearly average of 25 million kilowatt-hours per day, sufficient to power a city the size of Boston.
18. Kinetic energy – In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes, the same amount of work is done by the body in decelerating from its current speed to a state of rest. In classical mechanics, the energy of a non-rotating object of mass m traveling at a speed v is 12 m v 2. In relativistic mechanics, this is an approximation only when v is much less than the speed of light. The standard unit of energy is the joule. The adjective kinetic has its roots in the Greek word κίνησις kinesis, the dichotomy between kinetic energy and potential energy can be traced back to Aristotles concepts of actuality and potentiality. The principle in classical mechanics that E ∝ mv2 was first developed by Gottfried Leibniz and Johann Bernoulli, Willem s Gravesande of the Netherlands provided experimental evidence of this relationship. By dropping weights from different heights into a block of clay, Émilie du Châtelet recognized the implications of the experiment and published an explanation. The terms kinetic energy and work in their present scientific meanings date back to the mid-19th century, early understandings of these ideas can be attributed to Gaspard-Gustave Coriolis, who in 1829 published the paper titled Du Calcul de lEffet des Machines outlining the mathematics of kinetic energy. William Thomson, later Lord Kelvin, is given the credit for coining the term kinetic energy c, energy occurs in many forms, including chemical energy, thermal energy, electromagnetic radiation, gravitational energy, electric energy, elastic energy, nuclear energy, and rest energy. These can be categorized in two classes, potential energy and kinetic energy. Kinetic energy is the movement energy of an object, Kinetic energy can be transferred between objects and transformed into other kinds of energy. Kinetic energy may be best understood by examples that demonstrate how it is transformed to, for example, a cyclist uses chemical energy provided by food to accelerate a bicycle to a chosen speed. On a level surface, this speed can be maintained without further work, except to overcome air resistance, the chemical energy has been converted into kinetic energy, the energy of motion, but the process is not completely efficient and produces heat within the cyclist. The kinetic energy in the moving cyclist and the bicycle can be converted to other forms, for example, the cyclist could encounter a hill just high enough to coast up, so that the bicycle comes to a complete halt at the top. The kinetic energy has now largely converted to gravitational potential energy that can be released by freewheeling down the other side of the hill. Since the bicycle lost some of its energy to friction, it never regains all of its speed without additional pedaling, the energy is not destroyed, it has only been converted to another form by frictionKinetic energy – The cars of a roller coaster reach their maximum kinetic energy when at the bottom of their path. When they start rising, the kinetic energy begins to be converted to gravitational potential energy. The sum of kinetic and potential energy in the system remains constant, ignoring losses to friction.
19. Potential energy – In physics, potential energy is energy possessed by a body by virtue of its position relative to others, stresses within itself, electric charge, and other factors. The unit for energy in the International System of Units is the joule, the term potential energy was introduced by the 19th century Scottish engineer and physicist William Rankine, although it has links to Greek philosopher Aristotles concept of potentiality. Potential energy is associated with forces that act on a body in a way that the work done by these forces on the body depends only on the initial and final positions of the body in space. These forces, that are called potential forces, can be represented at every point in space by vectors expressed as gradients of a scalar function called potential. Potential energy is the energy of an object. It is the energy by virtue of a position relative to other objects. Potential energy is associated with restoring forces such as a spring or the force of gravity. The action of stretching the spring or lifting the mass is performed by a force that works against the force field of the potential. This work is stored in the field, which is said to be stored as potential energy. If the external force is removed the field acts on the body to perform the work as it moves the body back to the initial position. Suppose a ball which mass is m, and it is in h position in height, if the acceleration of free fall is g, the weight of the ball is mg. There are various types of energy, each associated with a particular type of force. Chemical potential energy, such as the energy stored in fossil fuels, is the work of the Coulomb force during rearrangement of mutual positions of electrons and nuclei in atoms and molecules. Thermal energy usually has two components, the energy of random motions of particles and the potential energy of their mutual positions. Forces derivable from a potential are also called conservative forces, the work done by a conservative force is W = − Δ U where Δ U is the change in the potential energy associated with the force. The negative sign provides the convention that work done against a force field increases potential energy, common notations for potential energy are U, V, also Ep. Potential energy is closely linked with forces, in this case, the force can be defined as the negative of the vector gradient of the potential field. If the work for a force is independent of the path, then the work done by the force is evaluated at the startPotential energy – In the case of a bow and arrow, when the archer does work on the bow, drawing the string back, some of the chemical energy of the archer's body is transformed into elastic potential-energy in the bent limbs of the bow. When the string is released, the force between the string and the arrow does work on the arrow. Thus, the potential energy in the bow limbs is transformed into the kinetic energy of the arrow as it takes flight.
20. Battery (electricity) – An electric battery is a device consisting of one or more electrochemical cells with external connections provided to power electrical devices such as flashlights, smartphones, and electric cars. When a battery is supplying power, its positive terminal is the cathode. The terminal marked negative is the source of electrons that when connected to a circuit will flow. It is the movement of ions within the battery which allows current to flow out of the battery to perform work. Historically the term specifically referred to a device composed of multiple cells. Primary batteries are used once and discarded, the materials are irreversibly changed during discharge. Common examples are the battery used for flashlights and a multitude of portable electronic devices. Secondary batteries can be discharged and recharged multiple times using mains power from a wall socket, examples include the lead-acid batteries used in vehicles and lithium-ion batteries used for portable electronics such as laptops and smartphones. According to a 2005 estimate, the battery industry generates US$48 billion in sales each year. Batteries have much lower energy than common fuels such as gasoline. This is somewhat offset by the efficiency of electric motors in producing mechanical work. The usage of battery to describe a group of electrical devices dates to Benjamin Franklin, alessandro Volta built and described the first electrochemical battery, the voltaic pile, in 1800. This was a stack of copper and zinc plates, separated by brine-soaked paper disks, Volta did not understand that the voltage was due to chemical reactions. Although early batteries were of value for experimental purposes, in practice their voltages fluctuated. It consisted of a pot filled with a copper sulfate solution, in which was immersed an unglazed earthenware container filled with sulfuric acid. These wet cells used liquid electrolytes, which were prone to leakage and spillage if not handled correctly, many used glass jars to hold their components, which made them fragile and potentially dangerous. These characteristics made wet cells unsuitable for portable appliances, near the end of the nineteenth century, the invention of dry cell batteries, which replaced the liquid electrolyte with a paste, made portable electrical devices practical. Batteries convert chemical energy directly to electrical energy, a battery consists of some number of voltaic cellsBattery (electricity) – Various cells and batteries (top-left to bottom-right): two AA, one D, one handheld ham radio battery, two 9-volt (PP3), two AAA, one C, one camcorder battery, one cordless phone battery.
21. Nuclear fusion – In nuclear physics, nuclear fusion is a reaction in which two or more atomic nuclei come close enough to form one or more different atomic nuclei and subatomic particles. The difference in mass between the products and reactants is manifested as the release of large amounts of energy and this difference in mass arises due to the difference in atomic binding energy between the atomic nuclei before and after the reaction. Fusion is the process that powers active or main sequence stars, the fusion process that produces a nucleus lighter than iron-56 or nickel-62 will generally yield a net energy release. These elements have the smallest mass per nucleon and the largest binding energy per nucleon, the opposite is true for the reverse process, nuclear fission. This means that the elements, such as hydrogen and helium, are in general more fusable, while the heavier elements. The extreme astrophysical event of a supernova can produce energy to fuse nuclei into elements heavier than iron. During the remainder of that decade the steps of the cycle of nuclear fusion in stars were worked out by Hans Bethe. Research into fusion for military purposes began in the early 1940s as part of the Manhattan Project, fusion was accomplished in 1951 with the Greenhouse Item nuclear test. Nuclear fusion on a scale in an explosion was first carried out on November 1,1952. Research into developing controlled thermonuclear fusion for civil purposes also began in earnest in the 1950s, the protons are positively charged and repel each other but they nonetheless stick together, demonstrating the existence of another force referred to as nuclear attraction. This force, called the nuclear force, overcomes electric repulsion at very close range. The effect of force is not observed outside the nucleus. The same force also pulls the nucleons together allowing ordinary matter to exist, light nuclei, are sufficiently small and proton-poor allowing the nuclear force to overcome the repulsive Coulomb force. This is because the nucleus is small that all nucleons feel the short-range attractive force at least as strongly as they feel the infinite-range Coulomb repulsion. Building up these nuclei from lighter nuclei by fusion thus releases the energy from the net attraction of these particles. For larger nuclei, however, no energy is released, since the force is short-range. Thus, energy is no longer released when such nuclei are made by fusion, instead, fusion reactions create the light elements that power the stars and produce virtually all elements in a process called nucleosynthesis. The fusion of elements in stars releases energy and the mass that always accompanies itNuclear fusion – The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen each second.
22. Meteorology – 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, regional, Meteorology, climatology, 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, transport, 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 then 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 also 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 thermoscopeMeteorology – Atmospheric sciences
23. Lightning – Lightning is a sudden electrostatic discharge that occurs during a thunder storm. This discharge occurs between electrically charged regions of a cloud, between two clouds, or between a cloud and the ground. The charged regions in the atmosphere temporarily equalize themselves through this discharge referred to as an if it hits an object on the ground. Lightning causes light in the form of plasma, and sound in the form of thunder, Lightning may be seen and not heard when it occurs at a distance too great for the sound to carry as far as the light from the strike or flash. This article incorporates public domain material from the National Oceanic and Atmospheric Administration document Understanding Lightning, the details of the charging process are still being studied by scientists, but there is general agreement on some of the basic concepts of thunderstorm electrification. The main charging area in a thunderstorm occurs in the part of the storm where air is moving upward rapidly and temperatures range from -15 to -25 Celsius. At that place, the combination of temperature and rapid upward air movement produces a mixture of super-cooled cloud droplets, small ice crystals, the updraft carries the super-cooled cloud droplets and very small ice crystals upward. At the same time, the graupel, which is larger and denser. The differences in the movement of the precipitation cause collisions to occur, when the rising ice crystals collide with graupel, the ice crystals become positively charged and the graupel becomes negatively charged. The updraft carries the positively charged ice crystals upward toward the top of the storm cloud, the larger and denser graupel is either suspended in the middle of the thunderstorm cloud or falls toward the lower part of the storm. The result is that the part of the thunderstorm cloud becomes positively charged while the middle to lower part of the thunderstorm cloud becomes negatively charged. This part of the cloud is called the anvil. While this is the charging process for the thunderstorm cloud. In addition, there is a small but important positive charge buildup near the bottom of the cloud due to the precipitation. Many factors affect the frequency, distribution, strength and physical properties of a lightning flash in a particular region of the world. These factors include ground elevation, latitude, prevailing wind currents, relative humidity, proximity to warm and cold bodies of water, to a certain degree, the ratio between IC, CC and CG lightning may also vary by season in middle latitudes. Lightnings relative unpredictability limits a complete explanation of how or why it occurs, the actual discharge is the final stage of a very complex process. At its peak, a thunderstorm produces three or more strikes to the Earth per minuteLightning – A lightning flash during a thunderstorm
24. Tornado – A tornado is a rapidly rotating column of air that spins while in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. Most tornadoes have wind speeds less than 110 miles per hour, are about 250 feet across, the most extreme tornadoes can attain wind speeds of more than 300 miles per hour, are more than two miles in diameter, and stay on the ground for dozens of miles. Various types of tornadoes include the multiple vortex tornado, landspout and waterspout, waterspouts are characterized by a spiraling funnel-shaped wind current, connecting to a large cumulus or cumulonimbus cloud. They are generally classified as non-supercellular tornadoes that develop over bodies of water and these spiraling columns of air frequently develop in tropical areas close to the equator, and are less common at high latitudes. Other tornado-like phenomena that exist in nature include the gustnado, dust devil, fire whirls, downbursts are frequently confused with tornadoes, though their action is dissimilar. Tornadoes have been observed and documented on every continent except Antarctica, however, the vast majority of tornadoes occur in the Tornado Alley region of the United States, although they can occur nearly anywhere in North America. There are several scales for rating the strength of tornadoes, the Fujita scale rates tornadoes by damage caused and has been replaced in some countries by the updated Enhanced Fujita Scale. An F0 or EF0 tornado, the weakest category, damages trees, an F5 or EF5 tornado, the strongest category, rips buildings off their foundations and can deform large skyscrapers. The similar TORRO scale ranges from a T0 for extremely weak tornadoes to T11 for the most powerful known tornadoes, Doppler radar data, photogrammetry, and ground swirl patterns may also be analyzed to determine intensity and assign a rating. The word tornado is a form of the Spanish word tronada. This in turn was taken from the Latin tonare, meaning to thunder and it most likely reached its present form through a combination of the Spanish tronada and tornar, however, this may be a folk etymology. A tornado is also referred to as a twister, and is also sometimes referred to by the old-fashioned colloquial term cyclone. The term cyclone is used as a synonym for tornado in the often-aired 1939 film The Wizard of Oz, the term twister is also used in that film, along with being the title of the 1996 tornado-related film Twister. A tornado is a rotating column of air, in contact with the ground, either pendant from a cumuliform cloud or underneath a cumuliform cloud. For a vortex to be classified as a tornado, it must be in contact with both the ground and the cloud base. Scientists have not yet created a definition of the word, for example. Tornado refers to the vortex of wind, not the condensation cloud and this results in the formation of a visible funnel cloud or condensation funnel. There is some disagreement over the definition of cloud and condensation funnelTornado – A tornado near Anadarko, Oklahoma. The funnel is the thin tube reaching from the cloud to the ground. The lower part of this tornado is surrounded by a translucent dust cloud, kicked up by the tornado's strong winds at the surface. The wind of the tornado has a much wider radius than the funnel itself.
25. Sunlight – Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is filtered through Earths atmosphere, and is obvious as daylight when the Sun is above the horizon, when the direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat. When it is blocked by clouds or reflects off other objects, the World Meteorological Organization uses the term sunshine duration to mean the cumulative time during which an area receives direct irradiance from the Sun of at least 120 watts per square meter. Other sources indicate an Average over the earth of 164 Watts per square meter over a 24 hour day. The ultraviolet radiation in sunlight has both positive and negative effects, as it is both a principal source of vitamin D3 and a mutagen. Sunlight takes about 8.3 minutes to reach Earth from the surface of the Sun. A photon starting at the center of the Sun and changing every time it encounters a charged particle would take between 10,000 and 170,000 years to get to the surface. Researchers may record sunlight using a sunshine recorder, pyranometer, or pyrheliometer, to calculate the amount of sunlight reaching the ground, both Earths elliptical orbit and the attenuation by Earths atmosphere have to be taken into account. In this formula dn–3 is used, because in modern times Earths perihelion, the closest approach to the Sun and, therefore, the value of 0.033412 is determined knowing that the ratio between the perihelion squared and the aphelion squared should be approximately 0.935338. The solar illuminance constant, is equal to 128×103 lx, the atmospheric extinction brings the number of lux down to around 100000. The total amount of energy received at ground level from the Sun at the zenith depends on the distance to the Sun and it is about 3. 3% higher than average in January and 3. 3% lower in July. In terms of energy, sunlight at Earths surface is around 52 to 55 percent infrared,42 to 43 percent visible, and 3 to 5 percent ultraviolet. At the top of the atmosphere, sunlight is about 30% more intense, having about 8% ultraviolet, direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux. This is higher than the efficacy of most artificial lighting, which means using sunlight for illumination heats up a less than using most forms of artificial lighting. Multiplying the figure of 1050 watts per square metre by 93 lumens per watt indicates that bright sunlight provides an illuminance of approximately 98000 lux on a surface at sea level. The illumination of a surface will be considerably less than this if the Sun is not very high in the sky. Averaged over a day, the highest amount of sunlight on a horizontal surface occurs in January at the South Pole, dividing the irradiance of 1050 W/m2 by the size of the suns disk in steradians gives an average radiance of 15.4 MW per square metre per steradian. Multiplying this by π gives a limit to the irradiance which can be focused on a surface using mirrors,48.5 MW/m2Sunlight – Sunlight shining through clouds, giving rise to crepuscular rays
26. Life – Various forms of life exist, such as plants, animals, fungi, protists, archaea, and bacteria. The criteria can at times be ambiguous and may or may not define viruses, viroids, biology is the primary science concerned with the study of life, although many other sciences are involved. The definition of life is controversial, the current definition is that organisms maintain homeostasis, are composed of cells, undergo metabolism, can grow, adapt to their environment, respond to stimuli, and reproduce. However, many other definitions have been proposed, and there are some borderline cases. Modern definitions are more complex, with input from a diversity of scientific disciplines, biophysicists have proposed many definitions based on chemical systems, there are also some living systems theories, such as the Gaia hypothesis, the idea that the Earth itself is alive. Another theory is that life is the property of systems, and yet another is elaborated in complex systems biology. Abiogenesis describes the process of life arising from non-living matter. Properties common to all organisms include the need for certain chemical elements to sustain biochemical functions. Life on Earth first appeared as early as 4.28 billion years ago, soon after ocean formation 4.41 billion years ago, Earths current life may have descended from an RNA world, although RNA-based life may not have been the first. The mechanism by which began on Earth is unknown, though many hypotheses have been formulated and are often based on the Miller–Urey experiment. The earliest known forms are microfossils of bacteria. In July 2016, scientists reported identifying a set of 355 genes believed to be present in the last universal ancestor of all living organisms. Since its primordial beginnings, life on Earth has changed its environment on a time scale. To survive in most ecosystems, life must often adapt to a range of conditions. Some microorganisms, called extremophiles, thrive in physically or geochemically extreme environments that are detrimental to most other life on Earth, Aristotle was the first person to classify organisms. Later, Carl Linnaeus introduced his system of nomenclature for the classification of species. Eventually new groups and categories of life were discovered, such as cells and microorganisms, cells are sometimes considered the smallest units and building blocks of life. There are two kinds of cells, prokaryotic and eukaryotic, both of which consist of cytoplasm enclosed within a membrane and contain many such as proteinsLife – Life (Biota / Vitae / Eobionti)
27. Chemical bond – A chemical bond is a lasting attraction between atoms that enables the formation of chemical compounds. The bond may result from the force of attraction between atoms with opposite charges, or through the sharing of electrons as in the covalent bonds. Since opposite charges attract via an electromagnetic force, the negatively charged electrons that are orbiting the nucleus. An electron positioned between two nuclei will be attracted to both of them, and the nuclei will be attracted toward electrons in this position and this attraction constitutes the chemical bond. This phenomenon limits the distance between nuclei and atoms in a bond, in general, strong chemical bonding is associated with the sharing or transfer of electrons between the participating atoms. All bonds can be explained by quantum theory, but, in practice, simplification rules allow chemists to predict the strength, directionality, the octet rule and VSEPR theory are two examples. Electrostatics are used to describe bond polarities and the effects they have on chemical substances, a chemical bond is an attraction between atoms. This attraction may be seen as the result of different behaviors of the outermost or valence electrons of atoms and these behaviors merge into each other seamlessly in various circumstances, so that there is no clear line to be drawn between them. However it remains useful and customary to differentiate different types of bond, which result in different properties of condensed matter. In the simplest view of a covalent bond, one or more electrons are drawn into the space between the two atomic nuclei, energy is released by bond formation. This is not as a reduction in energy, because the attraction of the two electrons to the two protons is offset by the electron-electron and proton-proton repulsions. In a polar covalent bond, one or more electrons are shared between two nuclei. Such weak intermolecular bonds give organic molecular substances, such as waxes and oils, their soft bulk character, also, the melting points of such covalent polymers and networks increase greatly. In a simplified view of a bond, the bonding electron is not shared at all. In this type of bond, the atomic orbital of one atom has a vacancy which allows the addition of one or more electrons. These newly added electrons potentially occupy a lower energy-state than they experience in a different atom, thus, one nucleus offers a more tightly bound position to an electron than does another nucleus, with the result that one atom may transfer an electron to the other. This transfer causes one atom to assume a net charge. The bond then results from electrostatic attraction between atoms and the atoms become positive or negatively charged ions, ionic bonds may be seen as extreme examples of polarization in covalent bondsChemical bond – Examples of Lewis dot -style representations of chemical bonds between carbon (C), hydrogen (H), and oxygen (O). Lewis dot diagrams were an early attempt to describe chemical bonding and are still widely used today.