PhenomenaLikelihood of trend Contraction of snow cover areas Increased thaw in permafrost regions Decrease in sea ice extent Virtually certain Increased frequency of hot extremes heat waves and heavy precipitation Very likely to occur Increase in tropical cyclone intensityLikely to occur Precipitation increases in high latitudesVery likely to occur Precipitation decreases in subtropical land regionsVery likely to occur Decreased water resources in many semi-arid areas including western U.S. and Mediterranean basin High confidence Global Climate Change: General Future Trends Definitions of likelihood ranges used to express the assessed probability of occurrence: virtually certain >99%, very likely >90%, likely >66%.

Environmental Health  Extreme weather and  Sea level rise – salinization of coastal water systems, flooding  Environmental degradation – land, coastal ecosystems, extinctions, fisheries collapse and loss of productivity Human Health  Forced population displacements - due to weather, flooding, water supply and coastal changes  Thermal stress – cyclones, bush fires and effects of food supplies  Disease - Microbial Proliferation and  Changes in host-vector relationships and in infectious disease ranges  Impaired food production

Predicted Changes : More Detailed