Definition of climate change

Scientists have understood since the 19th century that the earth’s climate might be changed by an increasing concentration of carbon dioxide in the atmosphere. Carbon dioxide, and similar gases, trap infra red radiation on earth that would otherwise dissipate into space. This is known as the “greenhouse effect” and the gases as “greenhouse gases”. As burning fossil fuels such as oil, coal and gas - on which modern economies rely - produces carbon dioxide in large quantities, this colourless, odourless and otherwise harmless gas has been identified as potentially dangerous to the environment.

What are the effects of climate change?

A little heating of the earth might not sound very dangerous. However, scientists now understand that heating the earth has other effects too. An increase in extreme weather, such as storms, droughts, floods and heatwaves can also result. Some areas grow drier, turning into deserts, while others grow wetter. Ice in the Arctic and Antarctic and glaciers on mountain tops may also melt, and this could push up the sea level. There is also a small risk of very extreme events: for instance, some scientists have posited that the Gulf Stream weather system that warms Europe could change direction under the influence of melting ice from the Arctic, which would have a drastic effect on Europe’s weather. [1]

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