Better technology lets scientists track world's glaciers

December 14, 2016

University of Alaska Fairbanks scientists are presenting their work at the American Geophysical Union’s fall meeting in San Francisco this week. Here are some highlights of their research, as shared at the world’s largest Earth and space science meeting.

Improved satellite technology is allowing researchers to more accurately measure how glacier ice could affect global sea levels.

A team of international scientists, including Mark Fahnestock of the University of Alaska Fairbanks Geophysical Institute, have studied thousands of satellite images taken since 2013 to gauge how rapidly glacier ice is being dumped into the ocean. The analysis, using data from the NASA-built Landsat 8 satellite, can track glacier movement of as little as 5 meters per year.

Better understanding the flow of glaciers into the ocean is critical to understanding the rate of sea-level rise, which has averaged about 3 mm per year in the past three decades. The new satellite data was discussed at a news conference on Monday at the American Geophysical Union’s fall meeting in San Francisco.

Glacial contribution to sea level rise has been mostly unknown, with reports from pilots or ground-based studies from scientists needed to determine how quickly glaciers are moving. Remote glaciers mostly went unmeasured.

“That’s the most rapid way we can put ice into the ocean, and it’s been the biggest uncertainty,” said Alex Gardner of the NASA Jet Propulsion Laboratory, who participated in the study.

The new technique allows precise satellite monitoring of the world’s glaciers and their rates of movement. In Alaska, about 1,000 kilometers of coastline from Seward to Petersburg have been analyzed for glacial movement.

That knowledge, along with glacial measurements around the globe, will allow researchers to better project the future rate of sea level rise.

“We are now watching all the glaciers of the earth changing in real time,” Fahnestock said.