Brief communication: Surface energy balance differences over Greenland between ERA5 and ERA-Interim

<p>We compare the main atmospheric drivers of the melt season over the Greenland Ice Sheet (GrIS) in ERA5 and ERA-Interim (ERAI) in their overlapping period 1979–2018. In summer, ERA5 differs significantly from ERAI, especially in the melt regions. Small-scale ERA5 <span class="inline-...

Full description

Bibliographic Details
Main Authors: U. Krebs-Kanzow, C. B. Rodehacke, G. Lohmann
Format: Article
Language:English
Published: Copernicus Publications 2023-12-01
Series:The Cryosphere
Online Access:https://tc.copernicus.org/articles/17/5131/2023/tc-17-5131-2023.pdf
_version_ 1797403596812189696
author U. Krebs-Kanzow
C. B. Rodehacke
C. B. Rodehacke
G. Lohmann
G. Lohmann
author_facet U. Krebs-Kanzow
C. B. Rodehacke
C. B. Rodehacke
G. Lohmann
G. Lohmann
author_sort U. Krebs-Kanzow
collection DOAJ
description <p>We compare the main atmospheric drivers of the melt season over the Greenland Ice Sheet (GrIS) in ERA5 and ERA-Interim (ERAI) in their overlapping period 1979–2018. In summer, ERA5 differs significantly from ERAI, especially in the melt regions. Small-scale ERA5 <span class="inline-formula">−</span> ERAI differences near the ice sheet's margins and over steep slopes can be explained by the different resolution, while the large-scale differences indicate a different representation of physical processes in the two reanalyses: averaged over the lower parts of the GrIS, the mean near-surface air temperature is 1 K lower, while the mean downward shortwave radiation at the surface is on average 15 <span class="inline-formula">W m<sup>−2</sup></span> higher than in ERAI. Comparison with observational weather station data shows a significant warm bias in ERAI and, for ERA5, a significant positive bias in downward shortwave radiation. Consequently, methods that previously estimated the GrIS surface mass balance from the ERAI surface energy balance need to be carefully recalibrated before converting to ERA5 forcing.</p>
first_indexed 2024-03-09T02:40:47Z
format Article
id doaj.art-d72f79ea6b6f4813bf070970bf80aaad
institution Directory Open Access Journal
issn 1994-0416
1994-0424
language English
last_indexed 2024-03-09T02:40:47Z
publishDate 2023-12-01
publisher Copernicus Publications
record_format Article
series The Cryosphere
spelling doaj.art-d72f79ea6b6f4813bf070970bf80aaad2023-12-06T06:09:50ZengCopernicus PublicationsThe Cryosphere1994-04161994-04242023-12-01175131513610.5194/tc-17-5131-2023Brief communication: Surface energy balance differences over Greenland between ERA5 and ERA-InterimU. Krebs-Kanzow0C. B. Rodehacke1C. B. Rodehacke2G. Lohmann3G. Lohmann4Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, GermanyAlfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, GermanyDanish Meteorological Institute, Copenhagen, DenmarkAlfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, GermanyDepartment of Environmental Physics and MARUM, University of Bremen, Bremen, Germany<p>We compare the main atmospheric drivers of the melt season over the Greenland Ice Sheet (GrIS) in ERA5 and ERA-Interim (ERAI) in their overlapping period 1979–2018. In summer, ERA5 differs significantly from ERAI, especially in the melt regions. Small-scale ERA5 <span class="inline-formula">−</span> ERAI differences near the ice sheet's margins and over steep slopes can be explained by the different resolution, while the large-scale differences indicate a different representation of physical processes in the two reanalyses: averaged over the lower parts of the GrIS, the mean near-surface air temperature is 1 K lower, while the mean downward shortwave radiation at the surface is on average 15 <span class="inline-formula">W m<sup>−2</sup></span> higher than in ERAI. Comparison with observational weather station data shows a significant warm bias in ERAI and, for ERA5, a significant positive bias in downward shortwave radiation. Consequently, methods that previously estimated the GrIS surface mass balance from the ERAI surface energy balance need to be carefully recalibrated before converting to ERA5 forcing.</p>https://tc.copernicus.org/articles/17/5131/2023/tc-17-5131-2023.pdf
spellingShingle U. Krebs-Kanzow
C. B. Rodehacke
C. B. Rodehacke
G. Lohmann
G. Lohmann
Brief communication: Surface energy balance differences over Greenland between ERA5 and ERA-Interim
The Cryosphere
title Brief communication: Surface energy balance differences over Greenland between ERA5 and ERA-Interim
title_full Brief communication: Surface energy balance differences over Greenland between ERA5 and ERA-Interim
title_fullStr Brief communication: Surface energy balance differences over Greenland between ERA5 and ERA-Interim
title_full_unstemmed Brief communication: Surface energy balance differences over Greenland between ERA5 and ERA-Interim
title_short Brief communication: Surface energy balance differences over Greenland between ERA5 and ERA-Interim
title_sort brief communication surface energy balance differences over greenland between era5 and era interim
url https://tc.copernicus.org/articles/17/5131/2023/tc-17-5131-2023.pdf
work_keys_str_mv AT ukrebskanzow briefcommunicationsurfaceenergybalancedifferencesovergreenlandbetweenera5anderainterim
AT cbrodehacke briefcommunicationsurfaceenergybalancedifferencesovergreenlandbetweenera5anderainterim
AT cbrodehacke briefcommunicationsurfaceenergybalancedifferencesovergreenlandbetweenera5anderainterim
AT glohmann briefcommunicationsurfaceenergybalancedifferencesovergreenlandbetweenera5anderainterim
AT glohmann briefcommunicationsurfaceenergybalancedifferencesovergreenlandbetweenera5anderainterim