Ian standing by a global positioning system (GPS) the team installed on an Antarctic Ice Stream.

Image by Ian Joughin of Antarctica's
Ice Speed (color) and Surface Topography (gray).

Photo by Richard Harris/NPR of Dry Valleys'
Taylor Glacier and Lake Bonney in Antarctica.

Revised October 2004

In the past few years, warming air and currents at the Poles have caused huge ice shelves on Greenland and Antarctic to melt and break off into the surrounding turbulent seas. Ian Joughin, a polar scientist and former student at the UW, has been conducting research in these polar areas. Antarctica is important because it stores 70 percent of the Earth's fresh water. In the unlikely event that all of Antarctica's ice sheets were to melt, the world's sea level would raise by 65-100 meters. Even if this vast reservoir contributes only several centimeters to sea level over the next century, it will have a significant economic impact on low lying coastal zones, such as New Orleans.

Before the development of satellite imagery of earth and the oceans, scientists, like Ian, could only use measurements they obtained working out in the field. But because of Antarctica's size, distance from other mainlands, and dangerous conditions, field work was slow and dangerous. That changed in 1997 when RADARSAT-1, a Canadian satellite, orbited over Antarctica and in only 18 days collected images of the entire continent. When polar scientists saw the high resolution and continental-scale that satellite mapping provided, they knew their access to ice sheet data had greatly improved.

Ian was an early contributor to the use of satellites to map Antarctica. He pioneered research into using satellite-borne radar to capture the topography of ice sheets and to estimate their ice stream motion. Using the ice motion data he derived, Ian studied ice sheet mass balance. Mass balance indicates the health of a glacier. If it gains more snow and ice than it loses in a year, the glacier has "positive" health or balance. Ian explains, "[calculating] Mass balance is very complicated especially trying to predict future mass balance." Due to this complication, Ian needs to know if the same sort of change occurring in one place on Antarctica is simultaneously occurring elsewhere on Antarctica.

To Ian's surprise his more recent processing of ice data has now led him to believe the warming and thinning process, started about 15,000 years ago, may have come to an end. Instead of losing ice, he estimates that although other parts of Antarctica are losing mass, a large sector of the West Antarctic ice sheet is gaining about 27 billion tons of ice.

Ian's research continues to focus on the collection of both space-borne and ground-based ice motion data that he uses to estimate mass balance and to determine variability in glacier flow. He also uses these data in conjunction with ice sheet models to gain insight into the controls on fast ice flow that are important in determining the rate of sea level change over the next few centuries.