Wind turbine

Global warming

Does global warming exist?

This may seem an unusual question to ask. There is no doubt that the Earth's temperature has increased over recent years but the cause of this rise is still questioned by some scientists. The majority of scientific opinion points to greenhouse gases, such as carbon dioxide, produced by burning fossil fuels as the main reason. Others argue the increase as part of the normal variation in temperature that has happened over the Earth's history.

Global temperature

Global temperatures and carbon dioxide levels

The increase in global temperature seen in the last 100 years (blue line) is thought to be due to greenhouse gases produced by human activity. The black line shows the increase in Carbon dioxide levels.

Some estimates suggest that global temperatures will rise by 1 - 2.5^oC in the next 50 years.

The Kyoto protocol aims to reduce emissions of greenhouse gases but some argue that it is too little, too late.

Carbon dioxide and the greenhouse effect

Forest fires cause devastation in areas where rainfall is reduced.
Picture: USDA.

Forest fires in the USA

Global warming and climate change

Changes in the earth's temperature may not sound too worrying. However, the potential effects of climate change could be more obvious.

Changes in weather patterns are extremely difficult to predict. Some people believe that the worst consequences of climate change could be droughts, water shortages, and disruption of food production.

Estimates of the effects of global warming vary greatly. If polar ice caps melt, it could cause sea levels to increase and flood some coastal regions. The Intergovernmental Panel on Climate Change (IPCC) estimates that rises in sea levels could put an extra 75 million people at risk of annual flooding.

Others argue that sea levels will rise by much less and the effects will not be so drastic.

Can we stop global warming?

Some people argue that global warming has started and that we can do little to stop it.

Others say that we are taking steps to reduce carbon dioxide and other greenhouse gas emissions. These actions will reduce the effects of global warming and that the predicted disasters will not happen.

Following the principles of sustainable development help to reduce human impacts on the environment. Better use of resources, more recycling and efficient production processes will all help to reduce the effects of global warming.