Fig. 1: Mass changes of the Greenland Ice Sheet between 2002 and 2019.

Time series of mass change from the GRACE and GRACE-FO missions (black, with 2-σ error bars) and simulations using the regional climate models MARv3.10³⁰ (A; light violet) and RACMO2.3p2³¹ (B; dark violet) and calibrated outflow measurements from feature tracking of optical and radar imagery (SMB-D*), updated from³² (“Methods” section). The top bar indicates the availability of GRACE and GRACE-FO measurements, the vertical dashed lines frame the data gap between both missions. The blue shading covers the biennial period 2017–2018, which contains the GRACE/GRACE-FO data gap (dotted line). The monthly SMB-D* data shown for MARv3.10 (A*; dark blue) are linearly interpolated to match the GRACE/GRACE-FO measurement timeframes. Both datasets are fitted with a biennial piecewise linear trend (breakpoints on January 1st of each year), revealing accelerated mass losses until 2012, followed by a slowdown and particularly small loss during the years 2017 and 2018. Values denote biennial mass balances in Gt year⁻¹.