CONSEQUENCES OF GLOBAL WARMING
The Intergovernmental Panel on Climate Change (IPCC) expects that the average global surface temperature could rise 1-4.5°F (0.6-2.5°C) in the next fifty years, and 2.2-10°F (1.4-5.8°C) in the next century, with significant regional variation.
Global warming leads naturally to a sea level rise
as the ice caps melt slowly under the action of increased temperatures.
The phenomenon is also increased by the ozone hole above the Antarctic
which allows the ultra-violet radiations to come directly on the southern
pole. Normally, these radiations should be stopped by the atmosphere but
the increased proportion of greenhouse gases created this hole. However,
the rise of the average sea level is especially provoked by the expansion of
the surface waters than by the melting of the ice caps and the Alpine
MalariaApproximately 270 million people suffer from malaria and 1 to 2 million people die from it yearly, while over 2 billion people are considered at risk of contracting the disease. Malaria generally extends only to places where the minimum winter temperature reaches no lower than 64.4ºF(18ºC). Small outbreaks now occurring north and south of tropical regions are consistent with model projections of potential shifts of conditions conducive to transmission. In the United States, locally transmitted malaria occurred in the 1990s during particularly hot, humid periods in California (as in the ‘80s), as well as in New Jersey, New York, Texas, Georgia, Florida, Michigan, Virginia and Toronto, Canada. One study suggests that the area that could sustain malaria transmission would increase from 45% of the globe to 60%, if atmospheric levels of greenhouse gases reach concentrations equivalent to a doubling of CO2 since the industrial revolution.
Dengue fever is a prolonged, severe flu-like illness, which in certain forms can be fatal. Unlike yellow fever (caused by a related virus and spread by the same mosquito) there is no vaccine for dengue fever. The mosquitoes that carry dengue fever (Aedes aegypti) are also limited by temperature. Frost kills adult mosquitoes and larvae and is therefore an important limiting factor for spread. Consistent with predictions associated with warming in mountain regions, dengue fever is now being reported at higher elevations at 1240 meters in Central America and 1700 meters in Mexico. The mosquito vector has been reported at 2200 meters in the Colombian Andes. Dengue fever may also be moving south, as its presence in northern Argentina and Australia suggest. Dengue fever (DF) and dengue hemorrhagic fever (DHF) now occur regularly in Asia and throughout Latin America. DF and DHF are among the more alarming of the resurging diseases, according to public health organizations, because of their epidemic nature and the lack of a vaccine.
Climate plays a role in maintaining the balance
among predators and their prey and the ratios of these “functional groups”
of species as natural biological controls over pests and pathogens (infectious