UGA leads NASA-funded study on ice sheet runoff’s impact on the ocean

Greenland 2013 Thomas Mote meltwater research-h.action
Researchers led by Asa Rennermalm of Rutgers University and including the University of Georgia's Thomas Mote measure meltwater runoff from the ice sheet margin in Greenland during summer 2013.

Athens, Ga. – Runoff from melting glaciers in West Greenland is producing dramatic changes in its ice sheet, though scientists don’t yet understand the effects these changes will have on the surrounding ocean.

A new $1.49 million interdisciplinary science grant from NASA will support efforts by University of Georgia faculty in the Franklin College of Arts and Sciences departments of geography and marine sciences to measure the effects of climate change on biological productivity in the ocean. The three-year research project on “From the Ice Sheet to the Sea: An Interdisciplinary Study of the Impact of Extreme Melt on Ocean Stratification and Productivity Near West Greenland” is a collaboration between UGA and scientists from the City College of New York, Rutgers University and Stanford University.

The study will examine the connection between Greenland ice sheet melt water and ocean productivity using remote sensing and modeling tools as well as data gathered on site. The work will examine the effect of melt on ocean circulation and mixing and investigate the role of ocean stratification and nutrients on ocean productivity.

Thomas Mote, professor and head of the department of geography, is principal investigator on the grant and, from UGA, is joined by Patricia Yager and Renato Castelao of the marine sciences department.

“The Labrador Sea off West Greenland plays a very important role on the circulation in the world’s ocean,” Castelao said. “However, we currently don’t understand how large freshwater inputs associated with ice melting will affect the circulation patterns in the region.”

The Greenland ice sheet occupies approximately 82 percent of the island of Greenland between the Arctic and Atlantic oceans. When ice sheets melt, ocean levels rise. A number of processes associated with melting, from the introduction of warmer, nutrient-rich freshwater into the ocean to decreases in the Arctic ice sheet to reflect sunlight, can affect biological productivity in the oceans.

“The questions we’re looking at will concentrate on issues stemming from the big discharges of water that were observed in 2012,” Mote said, such as “how those discharges are then affecting the stratification of the ocean, and how is that changing the biological productivity of the ocean, which then is going to affect the carbon budget of the ocean as well.”