The added value of high resolution in estimating the surface mass balance in southern Greenland
The polar version of the regional climate model RACMO2, version 2.3p1, is used to study the effect of model resolution on the simulated climate and surface mass balance (SMB) of south Greenland for the current climate (2007–2014). The model data at resolutions of 60, 20, 6.6, and 2.2 km are intercom...
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ftunivutrecht:oai:dspace.library.uu.nl:1874/397125 2023-07-23T04:19:32+02:00 The added value of high resolution in estimating the surface mass balance in southern Greenland van de Berg, W.J. van Meijgaard, Erik van Ulft, Lambertus H. Sub Dynamics Meteorology Marine and Atmospheric Research 2020-06-09 image/pdf https://dspace.library.uu.nl/handle/1874/397125 en eng 1994-0416 https://dspace.library.uu.nl/handle/1874/397125 info:eu-repo/semantics/OpenAccess Article 2020 ftunivutrecht 2023-07-02T03:10:21Z The polar version of the regional climate model RACMO2, version 2.3p1, is used to study the effect of model resolution on the simulated climate and surface mass balance (SMB) of south Greenland for the current climate (2007–2014). The model data at resolutions of 60, 20, 6.6, and 2.2 km are intercompared and compared to SMB observations using three different data refinement methods: nearest neighbour, bilinear interpolation, and a statistical downscaling method utilising the local dependency of fields on elevation. Furthermore, it is estimated how the errors induced by model resolution compare to errors induced by the model physics and initialisation. The results affirm earlier studies that SMB components which are tightly linked to elevation, like runoff, can be refined successfully, as soon as the ablation zone is reasonably well resolved in the source dataset. Precipitation fields are also highly elevation dependent, but precipitation has no systematic correlation with elevation, which inhibits statistical downscaling to work well. If refined component-wise, 20 km resolution model simulations can reproduce the SMB ablation observations almost as well as the finer-resolution model simulations. Nonetheless, statistical downscaling and regional climate modelling are complementary; the best results are obtained when high-resolution RACMO2 data are statistically refined. Model estimates in the accumulation zone do not benefit from statistical downscaling; hence, a resolution of about 20 km is sufficient to resolve the majority of the accumulation zone of the Greenland Ice Sheet with respect to the limited measurements we have. Furthermore, we demonstrate that using RACMO2, a hydrostatic model, at 2.2 km resolution led to invalid results as topographic and synoptic vertical winds exceed 10 m s−1, which violates the hydrostatic model assumptions. Finally, additional tests show that model resolution is as important as properly resolving spatial albedo patterns, correctly initialising the firn column, and ... Article in Journal/Newspaper Greenland Ice Sheet Utrecht University Repository Greenland |
institution |
Open Polar |
collection |
Utrecht University Repository |
op_collection_id |
ftunivutrecht |
language |
English |
description |
The polar version of the regional climate model RACMO2, version 2.3p1, is used to study the effect of model resolution on the simulated climate and surface mass balance (SMB) of south Greenland for the current climate (2007–2014). The model data at resolutions of 60, 20, 6.6, and 2.2 km are intercompared and compared to SMB observations using three different data refinement methods: nearest neighbour, bilinear interpolation, and a statistical downscaling method utilising the local dependency of fields on elevation. Furthermore, it is estimated how the errors induced by model resolution compare to errors induced by the model physics and initialisation. The results affirm earlier studies that SMB components which are tightly linked to elevation, like runoff, can be refined successfully, as soon as the ablation zone is reasonably well resolved in the source dataset. Precipitation fields are also highly elevation dependent, but precipitation has no systematic correlation with elevation, which inhibits statistical downscaling to work well. If refined component-wise, 20 km resolution model simulations can reproduce the SMB ablation observations almost as well as the finer-resolution model simulations. Nonetheless, statistical downscaling and regional climate modelling are complementary; the best results are obtained when high-resolution RACMO2 data are statistically refined. Model estimates in the accumulation zone do not benefit from statistical downscaling; hence, a resolution of about 20 km is sufficient to resolve the majority of the accumulation zone of the Greenland Ice Sheet with respect to the limited measurements we have. Furthermore, we demonstrate that using RACMO2, a hydrostatic model, at 2.2 km resolution led to invalid results as topographic and synoptic vertical winds exceed 10 m s−1, which violates the hydrostatic model assumptions. Finally, additional tests show that model resolution is as important as properly resolving spatial albedo patterns, correctly initialising the firn column, and ... |
author2 |
Sub Dynamics Meteorology Marine and Atmospheric Research |
format |
Article in Journal/Newspaper |
author |
van de Berg, W.J. van Meijgaard, Erik van Ulft, Lambertus H. |
spellingShingle |
van de Berg, W.J. van Meijgaard, Erik van Ulft, Lambertus H. The added value of high resolution in estimating the surface mass balance in southern Greenland |
author_facet |
van de Berg, W.J. van Meijgaard, Erik van Ulft, Lambertus H. |
author_sort |
van de Berg, W.J. |
title |
The added value of high resolution in estimating the surface mass balance in southern Greenland |
title_short |
The added value of high resolution in estimating the surface mass balance in southern Greenland |
title_full |
The added value of high resolution in estimating the surface mass balance in southern Greenland |
title_fullStr |
The added value of high resolution in estimating the surface mass balance in southern Greenland |
title_full_unstemmed |
The added value of high resolution in estimating the surface mass balance in southern Greenland |
title_sort |
added value of high resolution in estimating the surface mass balance in southern greenland |
publishDate |
2020 |
url |
https://dspace.library.uu.nl/handle/1874/397125 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_relation |
1994-0416 https://dspace.library.uu.nl/handle/1874/397125 |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1772182715147223040 |