Rapid ablation zone expansion amplifies north Greenland mass loss

Rapid ablation zone expansion amplifies north Greenland mass loss

Noël, Brice (Universiteit Utrecht)
van de Berg, Willem Jan (Universiteit Utrecht)
Lhermitte, S.L.M. (TU Delft Mathematical Geodesy and Positioning)
van den Broeke, Michiel R. (Universiteit Utrecht)

2019

Since the early 1990s, the Greenland ice sheet (GrIS) has been losing mass at an accelerating rate, primarily due to enhanced meltwater runoff following atmospheric warming. Here, we show that a pronounced latitudinal contrast exists in the GrIS response to recent warming. The ablation area in north Greenland expanded by 46%, almost twice as much as in the south (+25%), significantly increasing the relative contribution of the north to total GrIS mass loss. This latitudinal contrast originates from a different response to the recent change in large-scale Arctic summertime atmospheric circulation, promoting southwesterly advection of warm air toward the GrIS. In the southwest, persistent high atmospheric pressure reduced cloudiness, increasing runoff through enhanced absorption of solar radiation; in contrast, increased early-summer cloudiness in north Greenland enhanced atmospheric warming through decreased longwave heat loss. This triggered a rapid snowline retreat, causing early bare ice exposure, amplifying northern runoff.

http://resolver.tudelft.nl/uuid:a174eb48-7aae-4fbd-8194-aaab2eccc381

https://doi.org/10.1126/sciadv.aaw0123

2375-2548

Science Advances, 5 (9)

Institutional Repository

journal article

© 2019 Brice Noël, Willem Jan van de Berg, S.L.M. Lhermitte, Michiel R. van den Broeke