Spatial structures in the heat budget of the Antarctic Atmospheric Boundary Layer
Output from the regional climate model RACMO2/ANT is used to calculate the heat budget of the Antarctic atmospheric boundary layer (ABL). The main feature of the wintertime Antarctic ABL is a persistent temperature deficit compared to the free atmosphere. The magnitude of this deficit is controlled...
Main Authors: | , , |
---|---|
Other Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
2008
|
Subjects: | |
Online Access: | https://dspace.library.uu.nl/handle/1874/32447 |
id |
ftunivutrecht:oai:dspace.library.uu.nl:1874/32447 |
---|---|
record_format |
openpolar |
spelling |
ftunivutrecht:oai:dspace.library.uu.nl:1874/32447 2023-07-23T04:15:42+02:00 Spatial structures in the heat budget of the Antarctic Atmospheric Boundary Layer van der Berg, W.J. van den Broeke, M.R. van Meijgaard, E. Marine and Atmospheric Research Dep Natuurkunde 2008 text/plain https://dspace.library.uu.nl/handle/1874/32447 other unknown 1994-0416 https://dspace.library.uu.nl/handle/1874/32447 info:eu-repo/semantics/OpenAccess Article 2008 ftunivutrecht 2023-07-01T23:33:09Z Output from the regional climate model RACMO2/ANT is used to calculate the heat budget of the Antarctic atmospheric boundary layer (ABL). The main feature of the wintertime Antarctic ABL is a persistent temperature deficit compared to the free atmosphere. The magnitude of this deficit is controlled by the heat budget. During winter, transport of heat towards the surface by turbulence and net longwave emission are the primary ABL cooling terms. These processes show horizontal spatial variability only on continental scales. Vertical and horizontal advection of heat are the main warming terms. Over regions with convex ice sheet topography, i.e. domes and ridges, warming by downward vertical advection is enhanced due to divergence of the ABL wind field. Horizontal advection balances any excess warming caused by vertical advection, hence the ABL over domes and ridges tends to have a relatively weak temperature deficit. Conversely, vertical advection is reduced in regions with concave topography, i.e. valleys, where the ABL temperature deficit is enlarged. Along the coast, horizontal and vertical advection is governed by the inability of the large-scale circulation to adapt to small scale topographic features. Meso-scale (~10 km) topographic structures have thus a strong impact on the ABL winter temperature, besides latitude and surface elevation. During summer, this mechanism is much weaker; and the horizontal variability of ABL temperatures is smaller. Article in Journal/Newspaper Antarc* Antarctic Ice Sheet Utrecht University Repository Antarctic The Antarctic |
institution |
Open Polar |
collection |
Utrecht University Repository |
op_collection_id |
ftunivutrecht |
language |
unknown |
description |
Output from the regional climate model RACMO2/ANT is used to calculate the heat budget of the Antarctic atmospheric boundary layer (ABL). The main feature of the wintertime Antarctic ABL is a persistent temperature deficit compared to the free atmosphere. The magnitude of this deficit is controlled by the heat budget. During winter, transport of heat towards the surface by turbulence and net longwave emission are the primary ABL cooling terms. These processes show horizontal spatial variability only on continental scales. Vertical and horizontal advection of heat are the main warming terms. Over regions with convex ice sheet topography, i.e. domes and ridges, warming by downward vertical advection is enhanced due to divergence of the ABL wind field. Horizontal advection balances any excess warming caused by vertical advection, hence the ABL over domes and ridges tends to have a relatively weak temperature deficit. Conversely, vertical advection is reduced in regions with concave topography, i.e. valleys, where the ABL temperature deficit is enlarged. Along the coast, horizontal and vertical advection is governed by the inability of the large-scale circulation to adapt to small scale topographic features. Meso-scale (~10 km) topographic structures have thus a strong impact on the ABL winter temperature, besides latitude and surface elevation. During summer, this mechanism is much weaker; and the horizontal variability of ABL temperatures is smaller. |
author2 |
Marine and Atmospheric Research Dep Natuurkunde |
format |
Article in Journal/Newspaper |
author |
van der Berg, W.J. van den Broeke, M.R. van Meijgaard, E. |
spellingShingle |
van der Berg, W.J. van den Broeke, M.R. van Meijgaard, E. Spatial structures in the heat budget of the Antarctic Atmospheric Boundary Layer |
author_facet |
van der Berg, W.J. van den Broeke, M.R. van Meijgaard, E. |
author_sort |
van der Berg, W.J. |
title |
Spatial structures in the heat budget of the Antarctic Atmospheric Boundary Layer |
title_short |
Spatial structures in the heat budget of the Antarctic Atmospheric Boundary Layer |
title_full |
Spatial structures in the heat budget of the Antarctic Atmospheric Boundary Layer |
title_fullStr |
Spatial structures in the heat budget of the Antarctic Atmospheric Boundary Layer |
title_full_unstemmed |
Spatial structures in the heat budget of the Antarctic Atmospheric Boundary Layer |
title_sort |
spatial structures in the heat budget of the antarctic atmospheric boundary layer |
publishDate |
2008 |
url |
https://dspace.library.uu.nl/handle/1874/32447 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Ice Sheet |
genre_facet |
Antarc* Antarctic Ice Sheet |
op_relation |
1994-0416 https://dspace.library.uu.nl/handle/1874/32447 |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1772176648617066496 |