Greenland ice mass change since 2002
Key takeaways
- Greenland has lost about … gigatonnes of ice since 2002.
- That is enough water to raise global sea level by about … mm.
- Most of the loss happens in summer melt seasons, which show up as sharp drops each year. Record melt years such as 2012 and 2019 stand out clearly.
What are we looking at?
The chart shows the total change in the mass of the Greenland ice sheet since April 2002, measured month by month by the GRACE and GRACE Follow-On satellites. The sawtooth pattern is the seasonal cycle: snowfall adds mass in winter, and melt and iceberg calving remove more in summer. The long downward trend is the net loss.
Greenland loses ice in two roughly equal ways: meltwater running off its surface, and glaciers flowing faster into the ocean and calving icebergs. Warmer air drives the first. Warmer ocean water reaching the glacier fronts drives the second.
Why do we care?
Greenland is currently the single largest source of added water to the ocean. It holds enough ice to raise global sea level by about 7.4 m. Because of how Earth's gravity and rotation respond to melting ice, Greenland's losses raise sea level most in the Southern Hemisphere and along distant coasts, and actually lower it near Greenland itself.
Data: GRACE and GRACE-FO JPL mascon solution (RL06.3), via NASA Earth Indicators. Reference: Watkins, M.M. et al. (2015), doi:10.1002/2014JB011547.