TY - JOUR
T1 - Greenland ice sheet rainfall, heat and albedo feedback impacts from the mid-August 2021 atmospheric river
AU - Box, Jason E.
AU - Wehrlé, Adrien
AU - van As, Dirk
AU - Fausto, Robert S.
AU - Kjeldsen, Kristian K.
AU - Dachauer, Amrin
AU - Ahlstrøm, Andreas P.
AU - Picard, Ghislain
N1 - Funding Information:
This research was funded by the European Space Agency EO Sci for Society ESRIN CCN 4000125043/18/I‐NB. GEUS field observations of rainfall have been supported by Greenland Integrated Observing System (GIOS) under the Danish Agency for Higher Education and Science, the INTAROS project under the European Union's Horizon 2020 research and innovation program under grant agreement No. 727890 and the Danish Ministry of Climate, Energy and Utilities via The Programme for Monitoring of the Greenland Ice Sheet (PROMICE) and the Greenland Climate Network (GC‐Net). AGU data policy is followed with access to related data appearing in the data availability statement. We gratefully acknowledge PROMICE and GC‐Net engineers: Alan Pedersen; Jakob Jakobsen; Chris Shields, field workers: Dirk van As; Andreas Ahlstrøm; Chris Shields; Nanna Karlsson; Alan Pedersen; Derek Houtz and Øyvind Winton and the Swiss Federal Institute for Forest, Snow and Landscape Resarch (WSL) data scientists: Ionut Iosifescu and Rebecca Kurup. Baptiste Vandecrux is thanked for commenting on the manuscript. Stefan Hofer and an anonymous referee provided useful constructive suggestions as external reviewers.
Funding Information:
This research was funded by the European Space Agency EO Sci for Society ESRIN CCN 4000125043/18/I-NB. GEUS field observations of rainfall have been supported by Greenland Integrated Observing System (GIOS) under the Danish Agency for Higher Education and Science, the INTAROS project under the European Union's Horizon 2020 research and innovation program under grant agreement No. 727890 and the Danish Ministry of Climate, Energy and Utilities via The Programme for Monitoring of the Greenland Ice Sheet (PROMICE) and the Greenland Climate Network (GC-Net). AGU data policy is followed with access to related data appearing in the data availability statement. We gratefully acknowledge PROMICE and GC-Net engineers: Alan Pedersen; Jakob Jakobsen; Chris Shields, field workers: Dirk van As; Andreas Ahlstrøm; Chris Shields; Nanna Karlsson; Alan Pedersen; Derek Houtz and Øyvind Winton and the Swiss Federal Institute for Forest, Snow and Landscape Resarch (WSL) data scientists: Ionut Iosifescu and Rebecca Kurup. Baptiste Vandecrux is thanked for commenting on the manuscript. Stefan Hofer and an anonymous referee provided useful constructive suggestions as external reviewers.
Publisher Copyright:
© 2022 The Authors.
PY - 2022/6/16
Y1 - 2022/6/16
N2 - Rainfall at the Greenland ice sheet Summit 14 August 2021, was delivered by an atmospheric river (AR). Extreme surface ablation expanded the all-Greenland bare ice area to near-record-high with snowline climbing up to 788 ± 90 m. Ice sheet wet snow extent reached 46%, a record high for the 15–31 August AMSR data since 2003. Heat-driven firn deflation averaged 0.14 ± 0.05 m at four accumulation area automatic weather stations (AWSs). Energy budget calculations from AWS data indicate that surface heating from rainfall is much smaller than from either the sensible, latent, net-longwave or solar energy fluxes. Sensitivity tests show that without the heat-driven snow-darkening, melt at 1,840 m would have totaled 28% less. Similarly, at 1,270 m elevation, without the bare ice exposure, melting would have been 51% less. Proglacial river discharge was the highest on record since 2006 for late August and confirms the melt-sustaining effect of the albedo feedback.
AB - Rainfall at the Greenland ice sheet Summit 14 August 2021, was delivered by an atmospheric river (AR). Extreme surface ablation expanded the all-Greenland bare ice area to near-record-high with snowline climbing up to 788 ± 90 m. Ice sheet wet snow extent reached 46%, a record high for the 15–31 August AMSR data since 2003. Heat-driven firn deflation averaged 0.14 ± 0.05 m at four accumulation area automatic weather stations (AWSs). Energy budget calculations from AWS data indicate that surface heating from rainfall is much smaller than from either the sensible, latent, net-longwave or solar energy fluxes. Sensitivity tests show that without the heat-driven snow-darkening, melt at 1,840 m would have totaled 28% less. Similarly, at 1,270 m elevation, without the bare ice exposure, melting would have been 51% less. Proglacial river discharge was the highest on record since 2006 for late August and confirms the melt-sustaining effect of the albedo feedback.
KW - albedo feedback
KW - atmospheric river
KW - Greenland ice sheet
KW - heatwave
KW - rain on snow
KW - runoff
UR - http://www.scopus.com/inward/record.url?scp=85132177784&partnerID=8YFLogxK
U2 - 10.1029/2021GL097356
DO - 10.1029/2021GL097356
M3 - Article
AN - SCOPUS:85132177784
SN - 0094-8276
VL - 49
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 11
M1 - e2021GL097356
ER -
