MSU News Service

MSU researchers travel to the far north to study heat

May 04, 2004 -- By Jean Arthur, MSU News Service

Bozeman --"It's 15 degrees below zero Fahrenheit," says Joe Shaw, a professor of electrical and computer engineering at Montana State University. "That's reasonably warm. A few weeks ago, it was 50 below zero with wind whipping across the North Slope."

Shaw and five MSU students spent much of winter and early spring as far north as possible and still in the United States. They set up $100,000 worth of instruments near Barrow, Alaska in the frigid Arctic to collect data about heat.

Through the Atmospheric Radiation Measurement Program, the MSU team is gathering data about cloud and radiative processes at high latitudes--how much heat clouds radiate back toward earth. They use the data to refine models of weather patterns.

"The Arctic is very sensitive and gets little solar input," says Shaw. "In contrast, the tropics are bombarded with solar radiation. The arctic is where the signs of global warming should show up first because of polar cap melting. Global warming is more obvious in the Arctic because it has such a dramatic climate."

Using an Infrared Cloud Imager that they developed, Shaw and College of Engineering graduate students Mike Obland, Nathan Pust and Nathan Seldomridge, each spent a few weeks monitoring clouds and how those clouds radiate heat at high latitudes. Computer engineering senior Dusty Dunkle of Ronan and electrical engineering junior Paul Nugent of Fairfield, helped develop the instrument while another student, Brentha Thurairajah of Sri Lanka, analyzes the data as part of her master's degree work in electrical engineering.

Ice crystals coat outdoor surfaces. Temperature extremes can damage instruments. To collect the infrared information, the researchers use gold-plated mirrors and instruments with black lenses. Night vision technology allows them to gather data even during the dark of winter.

"The station is out in the middle of a snow and ice-covered field," says Obland, a Ph.D. candidate in physics from Colstrip. "While I have been here, the temperature has gone as high as minus 10 degrees Fahrenheit, down to minus 50. Our instruments have been working almost flawlessly, taking data every two minutes, 24 hours a day. My time here is spent watching the instrument and launching weather balloons every six hours beginning at 2 a.m."

The instrument takes pictures, like an ordinary digital camera, except at infrared wavelengths. They can access information through a Web site.

"At these wavelengths, which are not visible to the human eye, the sky and clouds look the same during the day as they do at night," says Seldomridge, a masters student in electrical engineering from Colorado Springs, Colo. "The images are calibrated and can be shown using a color key where each color represents the temperature of an ideal thermal source that would emit the amount of radiance that we actually measure. For example, a clear sky might be minus 80 degrees Celsius, while a cloud is a warmer, say, minus 10 degrees Celsius."

Seldomridge explains that clouds can shield earth from the sun, a cooling effect, but can also block thermal emission escaping from the earth, a warming effect. Details of cloud formation and statistics for the amount of cloud cover are helpful in building an accurate climate model.

"Cloud statistics are important to have day and night," says Pust, a Ph.D. candidate in electrical and computer engineering from Savage, Mont. "Climate model makers use the statistics to study atmospheric effects. These climate models should improve weather predictions."

Aside from dangers from temperatures, which can dip to minus 70 degrees, the MSU team had to be on the lookout for polar bears.

"We each read a detailed paper on polar bears because bears come into town and around the site especially if the ice moves in spring and bears get trapped in Barrow -- they get dangerous," says Shaw. He notes that scientists and engineers from the National Oceanic and Atmospheric Administration, the Department of Energy, and several universities in Italy conduct experiments at the site. "Fortunately, nobody has seen any bears this season."

Contact Joe Shaw 994-7261


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