ANN ARBOR---A 100-year-old stand of trees at the University of Michigan Biological Station will soon begin helping scientists learn more about global climate change and its impact on northern Michigan forests.

The U-M's 10,000-acre Biological Station, located near Pellston, Mich., is one of 24 North American sites selected by the U.S. Department of Energy to be part of its AmeriFlux network. State-of-the-art sensing instruments located on towers at these sites will measure the amount of carbon dioxide exchanged between the local ecosystem and the atmosphere. Instrument readings will be recorded about 10 times per second, 24 hours a day for several years.

"Legislators and policy makers want scientists to predict what's going to happen in the future as people continue to burn coal, oil and other fossil fuels which pump more carbon dioxide into the atmosphere," said James A. Teeri, director of the Biological Station and U-M professor of biology. "No one can make valid predictions now, because we don't know enough about how carbon dioxide cycles through the global ecosystem. AmeriFlux will begin to give us the information we need to answer these important questions."

Scientists know that the concentration of carbon dioxide in the atmosphere has climbed from 280 parts per million (ppm) in 1750 to today's level of about 360 ppm. The level of CO2 in the atmosphere started to increase when people began widespread burning of fossil fuels during the Industrial Revolution. Most scientists believe that the 1 degree C. rise in average global temperature recorded over this same time period has been caused, in part, by carbon dioxide and other "greenhouse gases" from fossil fuel emissions. These greenhouse gases trap heat in Earth's atmosphere and prevent it from radiating back out into space.

Scientists also know that growing plants take in carbon dioxide during photosynthesis. What no
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Contact: Sally Pobojewski
pobo@umich.edu
(734) 647-1844
University of Michigan
10-Apr-1998