NASA | Measuring Elevation Changes on the Greenland Ice Sheet

The Greenland ice sheet, covering a significant portion of the country, has the potential to raise global sea levels by 7.2 meters if it melts completely. NASA has been monitoring changes in the ice sheet since the late 1970s using satellites and airborne missions. Recent data shows varying patterns of ice thickening and thinning, influenced by bedrock topography and climate change. The Jakobshavn glacier has experienced significant mass loss due to increased calving and melting. Future missions aim to improve our understanding of these changes and their impact on global sea levels.

What is the potential impact on global sea levels if the Greenland ice sheet melts completely?

• It would increase by 3.6 meters.

• It would increase by 7.2 meters.

• It would remain unchanged.

• It would decrease by 7.2 meters.

What has NASA used to monitor changes in the Greenland ice sheet since the late 1970s?

• Icesat satellite and Operation Icebridge

• Ground-based telescopes

• Weather balloons and drones

• Seismic sensors and submarines

How does the bedrock topography affect the Greenland ice sheet?

• It has no effect on the ice sheet.

• It prevents any ice loss.

• It causes the ice sheet to thicken uniformly.

• It influences the size of basins drained by glaciers.

Which region of Greenland has experienced the most dramatic ice loss since the late 1990s?

• Central Greenland

• Jakobshavn glacier region

• Northeast Greenland

• Southeast Greenland

What factors have contributed to the increased glacier calving in the Jakobshavn glacier region?

• Decreased snowfall and volcanic activity

• Increased surface melt and warming ocean temperatures

• Increased snowfall and cooling ocean temperatures

• Decreased surface melt and cooling ocean temperatures