These changes may lead to a number of potentially serious consequences. The impacts of such extreme events on human welfare as well as natural ecosystems could be significant.
Climate change is likely to have wide-ranging and mostly adverse impacts on human health.
The projected increase in the duration and frequency of heat waves is expected to increase mortality rates as a result of heat stress, especially where air conditioning is not available. To a lesser extent, increases in winter temperatures in high latitudes could lead to decreases in mortality rates. Climate change is also expected to lead to increases in the potential transmission of many infectious diseases, including malaria, dengue, and yellow fever, extending the range of organisms such as insects that carry these diseases into the temperate zone, including parts of the United States, Europe, and Asia. This temperature increase is projected to occur somewhere in the time frame of 2040 to 2100. Both the magnitude of risk in current transmission areas and the area of potential transmission are projected to increase.