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	Global Warming or Climate Change
	Global warming drives climate change. Global warming is occurring at a faster rate each decade. In the UK we have seen 4 out of 5 of the hottest years ever recorded over a 330-year period in the last 10 years. These are startling statistics. This warming is due, at least in part, to the increasing concentrations of greenhouse gases in the atmosphere. The world is now warmer than at any time since the last Ice Age, and warming up faster than at any time in the last 500 million years. Global warming is caused by a blanket of 'greenhouse gases' building up around the earth trapping heat from the sun. The earth is kept warm and able to support life by the solar energy from the sun. This energy arrives in the form of short wave radiation most of which passes through the atmosphere to warm the earth's surface. The earth must be able to return energy into space at the same rate at which it absorbs energy in order not to overheat. The energy being returned to space is in the form of infra-red radiation and does not pass directly through the atmosphere. Above the atmosphere, the stratosphere and mesosphere are cooling faster than anybody thought. The heat trapped by the greenhouse gases in the lower troposhere causes the cooling. This is called radioative cooling and may be the "miner's canary" - the latest and largest sign that things are wrong. The cooling also creates more ice particles encouraging further ozone depletion. Lots of processes that influence the climate occur as the energy is transported through the atmosphere, it is absorbed by water vapour, carbon dioxide, methane, nitrous oxide and other natural 'greenhouse gases'. These gases act like a blanket around the earth. Human activity is adding to these greenhouse gases. During the last two hundred years vast stores of coal, oil and gas have been burnt that took millions of years to form. We have burnt fossil fuels faster than ever before releasing lots of carbon dioxide. Methane is mainly emitted as a by-product of oil wells - as 'natural gas.Nitrous oxide are emitted when nitrogen fertilsers break down. The same fertilisers need vast amounts of energy - by the Haber-Bosch process - to make. The main greenhouses gases are : Carbon dioxide mainly from burning fossil fuels. Chlorofluorocarbons (CFCs) used for propellants, foam plastics, refrigerants and solvents Nitrous oxides mainly from fossil fuels, industries, households, cement manufacture and burning rainforests Methane from cattle ranching, coal mines and paddy fields Each year the world pumps about 31,000 million tonnes of carbon and about 250 million tonnes of methane into the atmosphere. Vegetation and oceans absorb approximately half the carbon and 4/5ths of the methane produced, the remainder contribute to climate change and global warming. Industrialised regions such as Europe, North America and Japan have been responsible for most of the increase in greenhouse gases by the energy used to create and maintain the wealth and standard of living. More people are demanding better food, cleaner water, more electricity, more consumer goods increasing the demand for even more energy use. Developing countries want economic growth, the ability to expand their industries and their people aspire to a quality of life comparable with developed nations. S People are realising that the consequences of what was happening would affect the world long before the seas started to rise. The mixture of possible events is called climate change. Climate changes could have enormous consequences such as: food shortages as crops fail as a result of shorter wet winters and long dry summers violent storms and more hurricanes new pests and diseases melting of icecaps flooding of low lying areas as sea levels rise extinction of many plants and animals as conditions change. There are many arguments about climate change. This is not surprising as there are many vested interests in the debate.

• Land temperatures will go up 6C by the end of the next century
• The number of people on the coast subject to flooding will rise from 5 million now to 100 million by 2050
• Another 30 million people will be hungry in 50 years because of drought in Africa
• An extra 170 million people will live in countries with extreme water shortages

• Soil in the south become more droughty
• Wildlife migrate north
• Arable areas likely to move north
• Forest species increase in north, but beech in the south may die out
• Higher wind speeds will affect the design industry
• Increased claims for insurers
• Increasing incidence of infectious diseases and heat induced deaths.

For More Information:
Global Warming

UK government's "Climate Change"