The IPCC SRES developed a set of climate change cenarios that show various combinations of demographic, economic and technological driving forces could affect future GHG emissions. The various emissions projections under different SRES scenarios are widely used in the ssessments of future climate change.
The IPCC projects that the increase in global temperature by the end of this century is likely to be
in the range of 1.1 to 6.4°C, depending on which SRES scenario is used.
The projected effects of global warming include sea level rise (in the range of about 0.2 to 0.6 metres above 1990 levels by the end of the century), which will threaten low lying coastal areas, especially small islands and coastal cities, and melting glaciers, which will increase the risk of flooding. Other effects include the contraction of snow cover, permafrost and sea ice, increased frequency of heat waves, and more intense tropical cyclones.
Precipitation is projected to increase in many parts of the world and this can lead to an increased risk of flooding in many areas.
Temperature increases are likely to cause major changes in ecosystem structure and function, andcould place 20 to 30 percent of plant and animal species at increased risk of extinction. Changes in temperature and rainfall will have a damaging effect and terrestrial ecosystems, such as forests and savannahs. Climate change is also projected to greatly reduce water resources.
Declining crop yields due to higher temperatures will threaten food security and worsen malnutrition and starvation in many parts of the developing world, especially Africa. Human health would also be at risk due to an increase in vector-borne diseases such as malaria and dengue fever, and an increase in deaths due to heat stress as well as extreme cold in higher
latitudes is predicted.