Scientists agree that global warming is a real . What scientists don't yet know is how global warming will take place and how it will be. Industrialised or 'developed' countries are responsible for percent of greenhouse gases.

Greenhouse gases are gases in the atmosphere that trap heat around the earth but allow through. This means that the around the earth keeps getting hotter. There are more greenhouse gases in the atmosphere today than there were years ago. For example, carbon dioxide, has increased by percent over the past 100 years. Methane has increased by percent. Nitrous oxide, from burning fossil fuels and chemical fertilizers, has increased by percent.

Global warming has three main effects: rising sea levels, an increase in weather conditions, and an increased frequency of outbreaks of infectious diseases such as malaria and dengue fever. Sea levels have already risen by more than one in the past hundred years and are continuing to rise. If global warming is not slowed down, some nations will be completely covered by water.

Global warming also leads to extreme weather patterns such as El Nino. Weather patterns such as heavy storms, droughts and floods and have devastating effects on . Another effect of global warming is that the that carry infectious diseases such as malaria and dengue fever are able to survive in places that were previously too cold or too hot for them. This increases the percentage of the world's population that is exposed to these diseases - from 45 percent to percent.