Global climate change

Because there is a lag time between when greenhouse gases are emitted into the atmosphere and the effects they have, the climate change we are experiencing today results from the fossil fuels we burned decades ago.

The emissions of today will cause global warming in the future so it is important to reduce these emissions as much as possible. We can all make small changes which will lead to big reductions in greenhouse gas emissions.

Scientists have identified some of the likely effects of this warming globally.

Rainfall
Some regions of the world will experience more extreme rainfall while others will experience drought and in some regions, like the UK, these could alternate

Sea level
The sea level could rise by more than 40 centimetres by the end of the century. There are two reasons for this. First, as the water in the oceans warms, it expands. Second, ice from the polar caps and from glaciers is melting into the sea. Rising sea levels will completely swamp some small, low-lying island states and put millions of people in low-lying areas at risk.

Water
There will be less water available for irrigation and drinking because there will be less rain, and salt from rising sea levels will contaminate ground water in coastal areas. Droughts are likely to be more frequent. Three billion more people could suffer increased water shortages by 2080. Northern Africa, the Middle East and the Indian subcontinent will be the worst affected.

Harvests
As temperatures increase and rainfall patterns change, cereal crop yields are expected to drop significantly in Africa, the Middle East and India.

Disease
As temperatures increase, the areas that harbour diseases such as malaria, West Nile disease, dengue fever and river blindness will shift. It is predicted that 290 million additional people could be exposed to malaria by the 2080s, with China and Central Asia seeing the biggest increase in risk.

Rainforests
Higher temperatures and reduced rainfall could mean the loss of large areas of Brazilian and African rainforest – on top of the forest that we are cutting down to clear land for agriculture. These forests currently act as a 'sink' by absorbing large amounts of carbon dioxide which would otherwise be released into the atmosphere.