Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model
A new quasi-analytical mixed-layer model is formulated describing the evolution of the convective atmospheric boundary layer (ABL) during cold-air outbreaks (CAO) over polar oceans downstream of the marginal sea-ice zones. The new model is superior to previous ones since it predicts not only tempera...
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ftawi:oai:epic.awi.de:41430 2023-05-15T16:18:08+02:00 Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model Chechin, Dmitry Lüpkes, Christof 2017 https://epic.awi.de/id/eprint/41430/ https://hdl.handle.net/10013/epic.48339 unknown Springer Chechin, D. orcid:0000-0003-0021-9945 and Lüpkes, C. orcid:0000-0001-6518-0717 (2017) Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model , Boundary-Layer Meteorology, 162:91 , pp. 1-26 . doi:10.1007/s10546-016-0193-2 <https://doi.org/10.1007/s10546-016-0193-2> , hdl:10013/epic.48339 EPIC3Boundary-Layer Meteorology, Springer, 162:91, pp. 1-26 Article isiRev 2017 ftawi https://doi.org/10.1007/s10546-016-0193-2 2021-12-24T15:41:46Z A new quasi-analytical mixed-layer model is formulated describing the evolution of the convective atmospheric boundary layer (ABL) during cold-air outbreaks (CAO) over polar oceans downstream of the marginal sea-ice zones. The new model is superior to previous ones since it predicts not only temperature and mixed-layer height but also the height-averaged horizontal wind components. Results of the mixed-layer model are compared with dropsonde and aircraft observations carried out during several CAOs over the Fram Strait and also with results of a 3D non-hydrostatic (NH3D) model. It is shown that the mixed-layer model reproduces well the observed ABL height, temperature, low-level baroclinicity and its influence on the ABL wind speed. The mixed-layer model underestimates the observed ABL temperature only by about 10 %, most likely due to the neglect of condensation and subsidence. The comparison of the mixed-layer and NH3D model results shows good agreement with respect to wind speed including the formation of wind-speed maxima close to the ice edge. It is concluded that baroclinicity within the ABL governs the structure of the wind field while the baroclinicity above the ABL is important in reproducing the wind speed. It is shown that the baroclinicity in the ABL is strongest close to the ice edge and slowly decays further downwind. Analytical solutions demonstrate that the e-folding distance of this decay is the same as for the decay of the difference between the surface temperature of open water and of the mixed-layer temperature. This distance characterizing cold-air mass transformation ranges from 450 to 850 km for high-latitude CAOs. Article in Journal/Newspaper Fram Strait Sea ice Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Boundary-Layer Meteorology 162 1 91 116 |
institution |
Open Polar |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
A new quasi-analytical mixed-layer model is formulated describing the evolution of the convective atmospheric boundary layer (ABL) during cold-air outbreaks (CAO) over polar oceans downstream of the marginal sea-ice zones. The new model is superior to previous ones since it predicts not only temperature and mixed-layer height but also the height-averaged horizontal wind components. Results of the mixed-layer model are compared with dropsonde and aircraft observations carried out during several CAOs over the Fram Strait and also with results of a 3D non-hydrostatic (NH3D) model. It is shown that the mixed-layer model reproduces well the observed ABL height, temperature, low-level baroclinicity and its influence on the ABL wind speed. The mixed-layer model underestimates the observed ABL temperature only by about 10 %, most likely due to the neglect of condensation and subsidence. The comparison of the mixed-layer and NH3D model results shows good agreement with respect to wind speed including the formation of wind-speed maxima close to the ice edge. It is concluded that baroclinicity within the ABL governs the structure of the wind field while the baroclinicity above the ABL is important in reproducing the wind speed. It is shown that the baroclinicity in the ABL is strongest close to the ice edge and slowly decays further downwind. Analytical solutions demonstrate that the e-folding distance of this decay is the same as for the decay of the difference between the surface temperature of open water and of the mixed-layer temperature. This distance characterizing cold-air mass transformation ranges from 450 to 850 km for high-latitude CAOs. |
format |
Article in Journal/Newspaper |
author |
Chechin, Dmitry Lüpkes, Christof |
spellingShingle |
Chechin, Dmitry Lüpkes, Christof Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model |
author_facet |
Chechin, Dmitry Lüpkes, Christof |
author_sort |
Chechin, Dmitry |
title |
Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model |
title_short |
Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model |
title_full |
Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model |
title_fullStr |
Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model |
title_full_unstemmed |
Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model |
title_sort |
boundary-layer development and low-level baroclinicity during high-latitude cold-air outbreaks: a simple model |
publisher |
Springer |
publishDate |
2017 |
url |
https://epic.awi.de/id/eprint/41430/ https://hdl.handle.net/10013/epic.48339 |
genre |
Fram Strait Sea ice |
genre_facet |
Fram Strait Sea ice |
op_source |
EPIC3Boundary-Layer Meteorology, Springer, 162:91, pp. 1-26 |
op_relation |
Chechin, D. orcid:0000-0003-0021-9945 and Lüpkes, C. orcid:0000-0001-6518-0717 (2017) Boundary-Layer Development and Low-level Baroclinicity during High-Latitude Cold-Air Outbreaks: A Simple Model , Boundary-Layer Meteorology, 162:91 , pp. 1-26 . doi:10.1007/s10546-016-0193-2 <https://doi.org/10.1007/s10546-016-0193-2> , hdl:10013/epic.48339 |
op_doi |
https://doi.org/10.1007/s10546-016-0193-2 |
container_title |
Boundary-Layer Meteorology |
container_volume |
162 |
container_issue |
1 |
container_start_page |
91 |
op_container_end_page |
116 |
_version_ |
1766004257890238464 |