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Buildings on the edge of ice-covered lake.
Photo Courtesy: Woody Haywood/McMurdo science construction crew 
Carpenters build a new lab building, bottom right corner, at the Lake Bonney field camp so that it will be far enough away from flooding due to the rising lake level. Scientists who study the McMurdo Dry Valleys ecosystem say warmer temperatures are causing the lakes to rise rapidly, threatening field camps and science experiments. 

Flooded out

Rising lake levels in the McMurdo Dry Valleys affect science, field camps

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It’s certainly not a flood of biblical proportions, but rising lake levels and pulses of flooding events in the McMurdo Dry Valleys External U.S. government site are threatening established field camps — and could eventually change the nature of the cold desert ecosystem.

After what appears to have been a decade or so of aberrant cooling until the early 2000s, the Dry Valleys seem to have resumed a long-term trend of warming, according to John Priscu External Non-U.S. government site, a professor of ecology at Montana State University External Non-U.S. government site in Bozeman and an expert on the ice-covered lakes.

“They’re roughly changing together, although Lake Bonney, because of its steep sides and water input from the Taylor Glacier, is rising the fastest,” said Priscu of the three major lakes in the Taylor Valley, which harbors the most studied lakes of the ice-free valleys.

The McMurdo Dry Valleys have been the site of a Long Term Ecological Research (LTER) External Non-U.S. government site program beginning in 1993, though scientists have conducted studies there since the late 1950s. The exploration of the valleys, which sit at the edge of the massive East Antarctic Ice Sheet, dates back even further, to the turn of the 20th century, when Briton Robert F. Scott led an expedition through the region.

People push down a wall.
Photo Courtesy: Woody Haywood/McMurdo science construction crew
Construction workers tear down a lab building at Lake Bonney field camp that is being threatened by the rising waters.
White building in front of snow-covered mountain.
Photo Courtesy: Woody Haywood/McMurdo science construction crew
A new generator shack under construction uphill from the Lake Bonney field camp.
Building close to shore of lake.
Photo Courtesy: Woody Haywood/McMurdo science construction crew
The old field camp building at Lake Hoare was removed this year as water lapped at the front door.

In fact, thanks to Scott, whose team in 1903 measured a section of Lake Bonney, the westernmost lake in Taylor Valley, scientists today are able to extrapolate its growth during the intervening decades.

Between 1903 and 1973, when systematic monitoring began, the lake level rose about 12 meters, representing a 4 percent per year increase in flow, according to Diane McKnight External Non-U.S. government site, a professor at the University of Colorado at Boulder External Non-U.S. government site and the principal investigator for the McMurdo Dry Valleys LTER External Non-U.S. government site.

Lake Bonney appears to be rising faster than either Lake Fryxell or Lake Hoare to the east, partly due to its proximity to the Taylor Glacier. In fact, scientists have discovered that the glacier itself is adding water to the lake, which is about seven kilometers long and up to 900 meters wide. A narrow channel — the place where Scott’s men conducted their survey — separates the lake into east and west lobes.

“The Taylor Glacier is doing some very strange things. It’s adding a lot of water,” said Priscu, who has made 27 trips down to the Antarctic since 1983. “It’s gaining water from melting underneath.”

A field camp built in 1988 on the shores of Lake Bonney to support Priscu’s early research is slowly being moved to higher ground until a new facility is eventually constructed, according to Woody Haywood, who oversees the planning and building of science field camps for the U.S. Antarctic Program (USAP) External U.S. government site.

“About four years ago, it became painfully obvious that the trend was such that at Lake Bonney the water was rising at something measurable, and we’d soon have to address it,” Haywood said.

Over the last several years, the science construction team has removed two labs and replaced them with larger structures away from the shore. Haywood said the National Science Foundation (NSF) External U.S. government site, which manages the USAP, has initiated planning for new camps at Bonney and Fryxell, which is also being threatened by higher water levels.

“Both of those camps have small, restrictive lab space compared to the new ones that we’re designing and what we’ve been experimenting with at Lake Hoare,” Haywood said.1 2   Next

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Curator: Peter Rejcek, Antarctic Support Contract | NSF Official: Winifred Reuning, Division of Polar Programs