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The Energy Portal

Welcome to Wikipedia's Energy portal, your gateway to energy. This portal is aimed at giving you access to all energy related topics in all of its forms.

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Introduction

A plasma globe, using electrical energy to create plasma, light, heat, movement and a faint sound

In physics, energy (from Ancient Greek ἐνέργεια (enérgeia) 'activity') is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light. Energy is a conserved quantity—the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J).

Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, and the internal energy contained within a thermodynamic system. All living organisms constantly take in and release energy.

Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy.

Human civilization requires energy to function, which it gets from energy resources such as fossil fuels, nuclear fuel, or renewable energy. The Earth's climate and ecosystems processes are driven by the energy the planet receives from the Sun (although a small amount is also contributed by geothermal energy). (Full article...)

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Global warming is the increase in the average temperature of the Earth's near-surface air and oceans in recent decades and its projected continuation. Global average air temperature rose 0.74 ± 0.18 °C (1.3 ± 0.32 °F) during the past century. The Intergovernmental Panel on Climate Change concludes, 'most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.'

The effects of global warming are expected to include sea level rise, floods, drought and changes in the frequency and intensity of extreme weather events. Other effects may include changes in agricultural yields, reduced summer streamflows, species extinctions and increases in the ranges of disease vectors.

Concentrations of greenhouse gases are now considerably higher than at any time during the last 650,000 years, the extent of the ice core record. It is believed that CO₂ concentrations were last this high 20 million years ago. The primary international agreement on combating global warming is the Kyoto Protocol, which covers more than 160 countries and over 55% of global greenhouse gas emissions. The United States, the world's largest greenhouse gas emitter; Australia; and Kazakhstan have refused to ratify the treaty. China and India, two other large emitters, have ratified the treaty but are exempt from cutting emissions. International talks on a successor to the treaty, which ends in 2012, have begun.

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Photo credit: Charliebrown7034
Skyglow over New York City, one form of light pollution.

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Did you know?

The development of renewable energy in Iceland means that by 2050 the country should be the world's first zero-carbon economy?

World's two largest oil shale-fired power plants (Narva Power Plants) generate more than 90% of power in Estonia?

NW Natural in Portland, Oregon was the first gas company in the Pacific Northwest region of the United States when it started in 1859?

The Assistant Secretary of Energy for Fossil Energy is responsible for America's Strategic Petroleum Reserve?

Despite declines in production in recent years, Victoria still produces almost 20% of Australia's crude oil?

4.26 million tonnes of the Sun are converted to energy every second by nuclear fusion?

The first gasworks in the United Kingdom was built by the Gas Light and Coke Company, incorporated by Royal Charter in 1812?

The Baku–Tbilisi–Ceyhan pipeline was a central plot point in the James Bond film The World Is Not Enough?

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James E. Hansen (born March 29, 1941) heads the NASA Institute for Space Studies and is currently an adjunct professor in the Earth and Environmental Sciences department at Columbia University. He is best known for his testimony on climate change to congressional committees in the 1980s that helped raise broad awareness of global warming.

Hansen studied at the University of Iowa, obtaining a B.A. in Physics and Mathematics, an M.S. in Astronomy and a Ph.D. in Physics. He was elected to the National Academy of Sciences in 1996 and received the Heinz Environment Award for his research on global warming in 2001.

Hansen is a vocal critic of the Bush Administration's ideology on climate change. In 2005 and 2006, he claimed that NASA administrators have tried to influence his public statements about the causes of climate change. He has also claimed that the White House edited climate-related press releases from federal agencies to make global warming seem less threatening, and that he is unable to speak 'freely', without the backlash of other government officials.

Hansen has said that a global tipping point will be reached by 2016 if levels of greenhouse gases are not reduced. After this point global warming becomes unstoppable. As a result he claims that there may be a rise in sea levels by as much as 10 feet (3 metres) by 2100.