A study in the Jan. 2 edition of the British science journal Nature synthesized data from 143 scientific papers to examine whether a signal, or "fingerprint," of climate change can be found in how animals and plants have reacted to increasing temperatures.
Among their findings: In the temperate zone, the researchers estimate that, for species that have shown a change in timing, spring events are shifting about five days earlier every ten years.
One team member, fisheries and wildlife postdoctoral researcher Kimberly Hall at Michigan State University, helped wrangle data that comes not only from scientific outposts, but from the backyard recordings and personal journals of people across the world. The impact of global warming often appears as an early arrival of spring and is seen at bird feeders, heard in the earlier croaking of frogs and sniffed in the first waft of lilacs.
"Local weather is extremely variable from year to year, and animals and plants respond to many other factors besides temperature," Hall said. "To be able to detect impacts of climate warming, we have to have data sets that cover long periods, so trends can emerge from all of the noise."
The challenge: The average lifespan of a research grant is about three years. Few researchers focused on climate change 10 or 20 years ago, so many of the most convincing papers documenting long-term responses of wild plants and animals come from nonprofessional observers that were recording data as a hobby.
"The studies we reviewed often obtained data from persistent individuals, people who were curious about the wildlife around them and wrote down what they saw," she said. "Often the analyses that you can do with these types of data are pretty crude, but when they are combined with information from m
'"/>
Contact: Kimberly Hall
hallkim@msu.edu
517-282-8346
Michigan State University
1-Jan-2003