11 May 2008

Baikal Warms

Today is Mother's Day, and Mother Nature is not very happy to see Lake Baikal warming up. Why should we care?
Lake Baikal is the grand dame of lakes. In 1996, the United Nations Educational, Scientific and Cultural Organization (UNESCO) declared it a "World Heritage Site" because of its staggering biological diversity. It boasts more than 2,500 plant and animal species, most found nowhere else, including the world's only exclusively freshwater seal.

The lake actually contains 20 percent of the world's fresh water and could hold all of the water in the United States' Great Lakes combined. It is the world's deepest, most voluminous and oldest lake, at 25 million years old, which predates the emergence of humans.


The data on Lake Baikal reveal "significant warming of surface waters and long-term changes in the basal food web of the world's largest, most ancient lake," according to the researchers. "Increases in water temperature (1.2°C since 1946), chlorophyll a (300% since 1979) and an influential group of zooplankton grazers (335% since 1946) have important implications for nutrient cycling and food web dynamics."

The scientists conclude that the lake now joins other large lakes, including Superior, Tanganyika and Tahoe, for which contemporary warming trends also exist.

"But temperature changes in Lake Baikal are particularly significant as an integrated signal of long-term regional warming, because this lake is expected to be among those most resistant to climate change due to its tremendous volume and unique water circulation," they note.
Bottom Line: Climate change has not only been happening for a long time, but its effects are being felt in the most diverse places. If we do nothing, we will lose our most vulnerable resources (biodiversity hot spots). If we are able to respond effectively to global warming, we will be lucky to get away with only minor (but irrevocable) damage.