Cincinnati -- With winter's cold ready to zap at any moment, it may be difficult to remember the unrelenting heat waves of the summer of 1998 and the questions those blistering temperatures raised over global warming and its effects on climate. The mild autumn has added to the debate.
Working to address these concerns with cold, hard facts, University of Cincinnati geographer Ken Hinkel heads an international team that monitors temperature changes in regions of the world that are frozen.
Hinkel heads a multi-nation monitoring program that tracks temperatures in permafrost, the mixture of permanently frozen water, soil, organic matter and pockets of unfrozen brine found in 20 percent of the Earth's land area. These zones, found in the Arctic and mountainous regions, will be crucial indicators if global warming is occurring. "Permafrost regions may serve as a harbinger of global change as temperatures rise in response to increased atmospheric greenhouse gases," Hinkel said.
On Dec. 7, a colleague of Hinkel, Fritz Nelson of the University of Delaware, will report on monitoring results so far at a meeting of the American Geophysical Union in San Francisco.
Funded by a $374,612, five-year National Science Foundation grant, Hinkel has rounded up colleagues in more than 11 countries to collect and track temperature data and changes in permafrost. Among the nations participating are Austria, Canada, China, Denmark, Greenland, Kazakstan, Poland, Russia, Sweden, Switzerland, Tibet and the United States.
More sites are needed in Russia, in particular, because it encompasses so much of the Northern Hemisphere, and in Canada, where sites have dwindled due to budget cuts, according to the UC professor of geography. Antarctica is expected to be added to the list in 1999.
The more than two dozen researchers already participating have placed precise temperature sensors called thermisters at about 70 permafrost sites to measure and record air, surface and underground temperatures every hour. The saved data is downloaded by laptop computers and sent to UC for processing and analysis. Eventually, all data is fed to the National Snow and Ice Center at the University of Colorado and kept in a standardized database at the University of Cincinnati so that scientists can access it for further study.
For the past several years, Hinkel and his peers have voluntarily collected similar data, but the NSF grant allows the data collection to become more standardized, a crucial factor for scientific use. Each researcher in Hinkel s Circumpolar Active Layer Monitoring Program (CALM) follows the same procedure to take measurements at the same depths and at the same frequency so that the data can be compared from region to region.
Studying temperature readings from permafrost over time may also allow scientists to adjust climate simulation models they use in making predictions about the future and make them more realistic. Deep soil bores examined in previous decades by other researchers indicates that permafrost temperature has dropped from two to four degrees since the 1850s.
Hinkel typically travels to Alaska in August, after the mosquito season, and May, when the 24-hour days allow him to work long hours. He will be heading north again this May.
Working with Hinkel and Nelson on the NSF project is Jerry
Brown, a retired researcher who is active in the International
Permafrost Association. In June, Hinkel reported on this work at
the Seventh International Permafrost Conference in Yellowknife
(Northwest Territories), Canada. A UC graduate student will make
a presentation to the Association of American Geographers in
spring 1999 in Honolulu.