Assessing spatio-temporal variability and trends in modelled and measured Greenland Ice Sheet albedo (2000–2013)
Accurate measurements and simulations of Greenland Ice Sheet (GrIS) surface albedo are essential, given the role of surface albedo in modulating the amount of absorbed solar radiation and meltwater production. In this study, we assess the spatio-temporal variability of GrIS albedo during June, July,...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2014
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-8-2293-2014 https://doaj.org/article/f41adc74b45a4700955490abcd6ba640 |
id |
ftdoajarticles:oai:doaj.org/article:f41adc74b45a4700955490abcd6ba640 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:f41adc74b45a4700955490abcd6ba640 2023-05-15T16:28:39+02:00 Assessing spatio-temporal variability and trends in modelled and measured Greenland Ice Sheet albedo (2000–2013) P. M. Alexander M. Tedesco X. Fettweis R. S. W. van de Wal C. J. P. P. Smeets M. R. van den Broeke 2014-12-01T00:00:00Z https://doi.org/10.5194/tc-8-2293-2014 https://doaj.org/article/f41adc74b45a4700955490abcd6ba640 EN eng Copernicus Publications http://www.the-cryosphere.net/8/2293/2014/tc-8-2293-2014.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-8-2293-2014 https://doaj.org/article/f41adc74b45a4700955490abcd6ba640 The Cryosphere, Vol 8, Iss 6, Pp 2293-2312 (2014) Environmental sciences GE1-350 Geology QE1-996.5 article 2014 ftdoajarticles https://doi.org/10.5194/tc-8-2293-2014 2022-12-31T02:52:20Z Accurate measurements and simulations of Greenland Ice Sheet (GrIS) surface albedo are essential, given the role of surface albedo in modulating the amount of absorbed solar radiation and meltwater production. In this study, we assess the spatio-temporal variability of GrIS albedo during June, July, and August (JJA) for the period 2000–2013. We use two remote sensing products derived from data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS), as well as outputs from the Modèle Atmosphérique Régionale (MAR) regional climate model (RCM) and data from in situ automatic weather stations. Our results point to an overall consistency in spatio-temporal variability between remote sensing and RCM albedo, but reveal a difference in mean albedo of up to ~0.08 between the two remote sensing products north of 70° N. At low elevations, albedo values simulated by the RCM are positively biased with respect to remote sensing products by up to ~0.1 and exhibit low variability compared with observations. We infer that these differences are the result of a positive bias in simulated bare ice albedo. MODIS albedo, RCM outputs, and in situ observations consistently indicate a decrease in albedo of −0.03 to −0.06 per decade over the period 2003–2013 for the GrIS ablation area. Nevertheless, satellite products show a decline in JJA albedo of −0.03 to −0.04 per decade for regions within the accumulation area that is not confirmed by either the model or in situ observations. These findings appear to contradict a previous study that found an agreement between in situ and MODIS trends for individual months. The results indicate a need for further evaluation of high elevation albedo trends, a reconciliation of MODIS mean albedo at high latitudes, and the importance of accurately simulating bare ice albedo in RCMs. Article in Journal/Newspaper Greenland Ice Sheet The Cryosphere Directory of Open Access Journals: DOAJ Articles Greenland The Cryosphere 8 6 2293 2312 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 P. M. Alexander M. Tedesco X. Fettweis R. S. W. van de Wal C. J. P. P. Smeets M. R. van den Broeke Assessing spatio-temporal variability and trends in modelled and measured Greenland Ice Sheet albedo (2000–2013) |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Accurate measurements and simulations of Greenland Ice Sheet (GrIS) surface albedo are essential, given the role of surface albedo in modulating the amount of absorbed solar radiation and meltwater production. In this study, we assess the spatio-temporal variability of GrIS albedo during June, July, and August (JJA) for the period 2000–2013. We use two remote sensing products derived from data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS), as well as outputs from the Modèle Atmosphérique Régionale (MAR) regional climate model (RCM) and data from in situ automatic weather stations. Our results point to an overall consistency in spatio-temporal variability between remote sensing and RCM albedo, but reveal a difference in mean albedo of up to ~0.08 between the two remote sensing products north of 70° N. At low elevations, albedo values simulated by the RCM are positively biased with respect to remote sensing products by up to ~0.1 and exhibit low variability compared with observations. We infer that these differences are the result of a positive bias in simulated bare ice albedo. MODIS albedo, RCM outputs, and in situ observations consistently indicate a decrease in albedo of −0.03 to −0.06 per decade over the period 2003–2013 for the GrIS ablation area. Nevertheless, satellite products show a decline in JJA albedo of −0.03 to −0.04 per decade for regions within the accumulation area that is not confirmed by either the model or in situ observations. These findings appear to contradict a previous study that found an agreement between in situ and MODIS trends for individual months. The results indicate a need for further evaluation of high elevation albedo trends, a reconciliation of MODIS mean albedo at high latitudes, and the importance of accurately simulating bare ice albedo in RCMs. |
format |
Article in Journal/Newspaper |
author |
P. M. Alexander M. Tedesco X. Fettweis R. S. W. van de Wal C. J. P. P. Smeets M. R. van den Broeke |
author_facet |
P. M. Alexander M. Tedesco X. Fettweis R. S. W. van de Wal C. J. P. P. Smeets M. R. van den Broeke |
author_sort |
P. M. Alexander |
title |
Assessing spatio-temporal variability and trends in modelled and measured Greenland Ice Sheet albedo (2000–2013) |
title_short |
Assessing spatio-temporal variability and trends in modelled and measured Greenland Ice Sheet albedo (2000–2013) |
title_full |
Assessing spatio-temporal variability and trends in modelled and measured Greenland Ice Sheet albedo (2000–2013) |
title_fullStr |
Assessing spatio-temporal variability and trends in modelled and measured Greenland Ice Sheet albedo (2000–2013) |
title_full_unstemmed |
Assessing spatio-temporal variability and trends in modelled and measured Greenland Ice Sheet albedo (2000–2013) |
title_sort |
assessing spatio-temporal variability and trends in modelled and measured greenland ice sheet albedo (2000–2013) |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://doi.org/10.5194/tc-8-2293-2014 https://doaj.org/article/f41adc74b45a4700955490abcd6ba640 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet The Cryosphere |
genre_facet |
Greenland Ice Sheet The Cryosphere |
op_source |
The Cryosphere, Vol 8, Iss 6, Pp 2293-2312 (2014) |
op_relation |
http://www.the-cryosphere.net/8/2293/2014/tc-8-2293-2014.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-8-2293-2014 https://doaj.org/article/f41adc74b45a4700955490abcd6ba640 |
op_doi |
https://doi.org/10.5194/tc-8-2293-2014 |
container_title |
The Cryosphere |
container_volume |
8 |
container_issue |
6 |
container_start_page |
2293 |
op_container_end_page |
2312 |
_version_ |
1766018333967122432 |