Klinck, Dinniman Get Another Grant for Antarctic Ice Sheet Research
If sea levels around the globe rise significantly during the current century, one of the causes is likely to be sustained melting of the west Antarctica Ice Sheet. But predicting precisely where and how much the melting will be has proven to be difficult, and the National Science Foundation (NSF) has enlisted a team of scientists, including two Old Dominion University oceanographers, to try to solve that problem.
John Klinck, professor of ocean, earth and atmospheric sciences and director of the ODU Center for Coastal Physical Oceanography (CCPO), will be a team leader. Mike Dinniman, a research scientist with CCPO, is also a project investigator.
Other investigators on the grant, "Atmosphere-Ocean Coupling Causing Ice Shelf Melting in Antarctica," are David Holland of New York University and David Bromwich of Ohio State University. The project period begins Feb. 15 and extends through January 2014.
The basic goal of the project is to create a computer model of the ocean, atmosphere and ice that can predict on a relatively small spatial scale - say, for 10-kilometer-square blocks - the effects that changes in atmospheric temperatures and in ocean temperatures and circulation will have on the ice sheet.
Klinck said scientists know that the ice sheet is affected by climate trends of a decade or more, as well as climate phenomena such as the El Nino-Southern Oscillation that may cycle every four years or so. Small-spatial-scale effects in the atmosphere and ocean deliver heat to the bottom of the floating edges of the ice sheet, which are called ice shelves. The ice shelves in the Amundsen Sea embayment in the Pacific sector of Antarctica have been found in recent years to be experiencing accelerated melting. As the ice shelves are already floating, their melting will have little effect on global sea level. However, it is believed that weakening or removal of the ice shelves will speed up the flow of ice from off the land mass to the ocean, which does lead to sea-level rise.
"Therefore, a numerical model must have the spatial resolution to simulate and understand the processes that melt the floating ice shelves," Klinck said.
The researchers' model will put together existing computer models of the atmosphere, ocean, floating ice shelves and sea ice to allow a better understanding of past decadal variability and its influences on melting ice shelves, as well as projecting the effect of estimated future changes.
"First, simulations of the past 20-40 years will be done to understand past variability," Klinck explained. "Then, projections of future conditions will be obtained from global climate simulations and used to force our regional model - the process is called downscaling - in order to project these changes on the regional processes around the Antarctic coast."
Klinck, Dinniman and another CCPO researcher, Eileen Hofmann, a professor of ocean, earth and atmospheric sciences,have done numerous scientific studies that look closely at what is happening in the Antarctic region in order to better understand global phenomena.
This latest NSF grant is for $150,000 for the three-year project. Klinck and Dinniman also have been supported by other NSF grants totaling more than $500,000 to study the reasons for the increasing rate of melting of the West Antarctic Ice Sheet.
In addition, Hofmann, Klinck and Dinniman are investigators on two NSF grants totaling $450,000 awarded in the summer of 2009 for research in the Ross Sea off Antarctica. Dinniman did field work in Antarctica late last year on one of the projects, which uses a robotic underwater glider to measure temperature, salinity and other conditions at various ocean depths.