Changes in climate threaten remaining wetlands, particularly for ecosystems that lie within the Great Lakes basin. Recent studies have shown that the largest hydrological impacts from warming temperatures will be in the southern portion of the basin. If runoff is reduced, wetland habitats that depend on inundation of freshwater from the lake could be adversely affected. An increase in climatic variability suggests that frequency and severity of wildfires could increase, which could affect already dry sites such as sand dune and oak savannah habitats. The small area and history of fire suppression in these ecosystems could increase their vulnerability.
Wetlands play a major role in river basin hydrology and serve as important wildlife habitats.
Changes in water levels brought about by a changing climate could dramatically alter the extent of these ecosystems and endanger resident flora and fauna. For example, warmer air temperatures could lead to reduced stream flow and warmer water temperatures, which would significantly impair reproduction of fish and other animals and favor the spread of exotic species that exhibit a high tolerance for extreme environmental conditions.