Global Warming

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Global Warming is the increase in global temperature of about half a degree Centigrade per hundred years which has been recorded since measurements began about 150 years ago. This might not seem much, but it is a very significant change. It has already affected human life. The past few years have seen bush and forest fires, storms, death from overheating and wars caused by crop failure. Current predictions by the Intergovernmental Panel on Climate Change (IPCC) are that things will get worse over the next hundred years. Governments are worried. Climate change could lead to famine, floods, new diseases and large movements of populations.

This is one of the most serious problems facing the world today, and of course it is a global problem which, if there is a solution to it, can only be found by taking global action. To get the complete picture we need to understand the following views of the problem.

Cosmic View
The Sun is a variable star, and the power it generates changes. This may affect the climate.
Also the Sun travels round the Milky Way Galaxy, and on its journey it can pass through clouds of gas and dust which can affect the energy reaching the Earth, although this is not likely to be a cause of global warming, it could affect the climate over millions of years.

Earth View
The Earth is a changing planet. Its continents drift about and its magnetic field changes. These changes can affect the climate.

Life View
Life can affect the climate because plants absorb carbon dioxide which decreases the greenhouse affect. On the other hand when animals eat plants or people burn them they release carbon dioxide, which increases the greenhouse effect.

Human View
Humans burn fossil fuels such as coal and oil, as well as burning forests. This burning releases carbon dioxide which increases the greenhouse effect

The IPCC clearly states that greenhouse gases created by burning fossil fuels are responsible for most of the observed temperature increase since the middle of the twentieth century.