Partitioning Recent Greenland Mass Loss
Michiel van den Broeke,1,*
Jonathan Bamber,2
Janneke Ettema,1
Eric Rignot,3,4
Ernst Schrama,5
Willem Jan van de Berg,1
Erik van Meijgaard,6
Isabella Velicogna,3,4
Bert Wouters5,6
Mass budget calculations, validated with satellite gravity observations
[from the Gravity Recovery and Climate Experiment (GRACE) satellites],
enable us to quantify the individual components of recent Greenland
mass loss. The total 2000–2008 mass loss of ~1500 gigatons,
equivalent to 0.46 millimeters per year of global sea level
rise, is equally split between surface processes (runoff and
precipitation) and ice dynamics. Without the moderating effects
of increased snowfall and refreezing, post-1996 Greenland ice
sheet mass losses would have been 100% higher. Since 2006, high
summer melt rates have increased Greenland ice sheet mass loss
to 273 gigatons per year (0.75 millimeters per year of equivalent
sea level rise). The seasonal cycle in surface mass balance
fully accounts for detrended GRACE mass variations, confirming
insignificant subannual variation in ice sheet discharge.
2 Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, UK.
3 Department of Earth System Science, University of California, Irvine, CA, USA.
4 Jet Propulsion Laboratory, Pasadena, CA, USA.
5 Delft Institute of Earth Observation and Space Systems, Delft University of Technology, Delft, Netherlands.
6 Royal Netherlands Meteorological Institute, De Bilt, Netherlands.
* To whom correspondence should be addressed. E-mail: m.r.vandenbroeke{at}uu.nl
