Biodiversity (12/17/2007)

The most studied and best understood impact of climate change is phenological changes, which are alterations in the timing of periodic biological events, such as the onset of animal migration or plant blooming, in response to climatic conditions. These events are typically linked to climate and are predicted to occur increasingly early in response to Earth’s steady warming; unfortunately, an increasing number of scientific studies present evidence consistent with this prediction.

A second category of climate change effects are shifts in the range of a species, with movement in the long term expected to be toward each pole and to higher altitudes. Once again, a growing body of scientific evidence supports this. Near Antarctica, for instance, data indicate that several species of penguins, both sea ice–dependent and ocean-going species, have moved southward toward the pole

These numerous studies indicate quite clearly that climate change has had a significant effect on terrestrial biodiversity, causing significant changes in a number of organisms across a wide array of ecosystems. Will these changes continue? And what will be their long-term effects? The IPCC and Millenium Ecosystem Assessment (MA) reports address the first of these questions. The IPCC concluded that it is “virtually certain” that recent warming trends will continue, and the MA projected that the impacts of climate change on biodiversity across all ecosystems will increase very rapidly.