Projection of future changes in climate
According to IPCC, there is strong evidence that with the current environmental policies and sustainable development practises, the global emissions of greenhouse gases will continue to grow. The best estimate of global surface temperature increase of the 21st century ranges from 1.8°C (likely range is 1.1°C to 2.9°C) for the low scenario of CO2 emission to 4.0°C (likely range is 2.4°C to 6.4°C) for high CO2 emission. These results obtained by the IPCC (2007) have been retained by a series of coupled atmosphere-ocean numerical model simulations.
With these projections scientist can assess the future impact of climate change. It is very likely that the frequency of hot extremes, heat waves and heavy precipitation will increase. By mid-century, annual river runoff and water availability in high latitudes and in certain tropical wet areas will increase, while they are projected to decrease in some dry mid-latitude and tropic regions. Many semi-arid areas (Mediterranean Basin, western United States, southern Africa and north-eastern Brazil) will suffer from lack of water supplies.
Climate change global processes and effects. Source: UNEP/GRID-Arendal.
Human societies will be beyond doubt affected by these climate changes. In many places, especially in Africa, the rain-fed agriculture could be seriously reduced and the access to food will become even more limited which will further deepen existing world problems of malnutrition and food security.
On the contrary, people in the coastal regions will have to face more frequent and more intense floods and storms and other natural hazards that threaten their habitats. Together with rising sea level (during the 21st century global average sea level is projected to rise by more than a 0.7 metre for the worst scenario) these weather extremes will pose a serious threat to one tenth of global populations living in the coastal areas that lie within 10 metres above current sea level. Migration of people from those coasts would impact patterns of human settlements on a global scale.
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Economists help climate scientists to improve global warming forecasts. A press release on ESF explanatory workshop |
ESF provides the scientific, administrative and technical secretariat for COST (European Cooperation in Science and Technology).