Sunday, April 24, 2016

April 24: Joint Expedition to Measure Historic Snowfall in Greenland

Original story by Becca Burke at Boise State University

Tate starting to snowmobile in Idaho
While some on the Boise State campus are preparing for hot summer days and barbecues, graduate student Tate Meehan is preparing for frigid temperatures and hard work. 

Meehan, who is in the first year of his master’s program in geophysics, is headed to a research expedition on Greenland. He’ll be joined by Forrest McCarthy, a mountaineering guide from the Wilderness Wildland Alliance and National Science Foundation Polar Programs, Dartmouth polar geoscientist Erich Osterberg, and Dartmouth doctoral students Gabe Lewis and Thomas Overly. 

The combined Boise State and Dartmouth research team will study and measure snowfall amounts over the past 50 years in an area that contains some of the largest snowfall variances on the Greenland ice sheet. This expedition comes at a precarious time; in recent weeks Greenland’s early melting season, brought on by unseasonably warm weather, has some global researchers concerned.

“This trip is especially critical this year as Greenland has experienced the warmest first four months on average in its recorded history, which dates back to the 1870s. It’s the onset of melting that has happened about two months ahead of schedule that makes our job a lot more challenging,” Meehan said. 

The view from our test site in Idaho
The research team begins their expedition in Greenland at the NSF deep field station Camp Raven in southwest Greenland and will travel 1,700 kilometers from Southwest Greenland to the summit of the ice cap. The team will use a variety of Boise State radar systems to track the subsurface snow layers, and will continuously measure the journey to the summit. The age of the layers will then be determined by a geochemistry analysis of 60-foot core sample sections of ice and snow. The research data gathered from each sample site allows for estimation on annual snowfall amounts dating back over 50 years. 

During the seven-week expedition, the research team will travel by snowmobile and live in tents. In addition to mapping new areas for measurement, they will also revisit multiple Program for Artic Regional Climate Assessment (PARCA) sites. PARCA was launched by NASA in 1993 with the primary goal of measuring and understanding the mass balance of the Greenland ice sheet.
Towing radar equipment with a snowmobile
The Greenland field expedition is funded by a collaborative NSF Office of Polar Programs grant between Boise State and Dartmouth. The principal investigators from Boise State are geoscientists H.P. Marshall and John Bradford, and for Dartmouth, they are Osterberg and Bob Hawley. This trip to Greenland will include detailed core sample analysis and radar observations completing half the full traverse; a second trip will be completed next year. 

This research continues previous work in Greenland conducted by Marshall and Bradford. Bradford’s radar inversion work completed with Boise State doctorate student Joel Brown and University of Montana glaciologist Joel Harper will be applied to the radar data collected during this research trip. Marshall conducted radar measurements in 2010 and built a radar system used for a traverse from the summit to Thule Air Base. 

The research being conducted during this trip and the subsequent trip next year holds significant relevance for the future of the planet and research into climate change. 

“This project is important, because we don’t know much about the snowfall amounts in this area,” Marshall explained. “The snowfall in this area is changing and controls the behavior of a large part of the ice sheet. The behavior of the ice sheet is important because it is the major contribution to global sea level rise, and affects global climate.”

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