The east slope of the Andes in southern Peru.

Miles Silman and Mark Bush

Animals and plants in the Andes may be particularly vulnerable to rapid global warming, new research suggests.

A study of Andean climate over the past 48,000 years reveals that temperatures in the region rose relatively gradually — at a rate of 5°C over several millennia, compared to 5°C over two centuries in North America at the end of the ice age.

The US-based researchers examined pollen trapped in sediment in Lake Consuelo, Peru, as part of the study, which is published in this week's issue of Science. They warn that the rapid temperature rises that are predicted to occur over the next century due to human-induced climate change may threaten the region's biodiversity. This includes lower mountain cloud forests, one of the world's most threatened habitats

"According to the Intergovernmental Panel on Climate Change, we can expect a minimum of 1-2°C increase in temperature in the Andes by the end of this century," says one of the researchers, Mark Bush of the Florida Institute of Technology. "Our record shows that climate change of this kind has never happened in the past 48,000 years. It is not a natural phenomenon."

Bush predicts that animals that easily migrate will have a better chance of surviving, as will plants that can grow under a wide variety of conditions. However, the researchers warn that at the predicted rate of climate change some species may be unable to survive within only one or two plant generations.

Link to research paper by Mark Bush et al in Science

Reference: Science 303, 827 (2003)