Arctic Atmospheric Rivers : Eulerian and Lagrangian features, and trends over the last 40 years
Arctic Atmospheric rivers, termed ‘warm-and-moist intrusion’ (WaMAI) in this thesis, transporting heat and moisture into the Arctic from lower latitudes, is a key contributor to the amplified warming in the Arctic under global change (Arctic Amplification). However, the warming effect of WaMAIs and...
Main Author: | |
---|---|
Format: | Doctoral or Postdoctoral Thesis |
Language: | English |
Published: |
Stockholms universitet, Meteorologiska institutionen (MISU)
2021
|
Subjects: | |
Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-198079 |
id |
ftstockholmuniv:oai:DiVA.org:su-198079 |
---|---|
record_format |
openpolar |
spelling |
ftstockholmuniv:oai:DiVA.org:su-198079 2023-05-15T14:37:39+02:00 Arctic Atmospheric Rivers : Eulerian and Lagrangian features, and trends over the last 40 years You, Cheng 2021 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-198079 eng eng Stockholms universitet, Meteorologiska institutionen (MISU) Stockholm : Department of Meteorology, Stockholm University http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-198079 urn:isbn:978-91-7911-672-9 urn:isbn:978-91-7911-673-6 info:eu-repo/semantics/openAccess Arctic Atmospheric river Stratocumulus Blocking Turbulence Longwave irradiance Meteorology and Atmospheric Sciences Meteorologi och atmosfärforskning Doctoral thesis, comprehensive summary info:eu-repo/semantics/doctoralThesis text 2021 ftstockholmuniv 2023-02-23T21:42:34Z Arctic Atmospheric rivers, termed ‘warm-and-moist intrusion’ (WaMAI) in this thesis, transporting heat and moisture into the Arctic from lower latitudes, is a key contributor to the amplified warming in the Arctic under global change (Arctic Amplification). However, the warming effect of WaMAIs and its transformation along the trajectories into high Arctic still remain unclear, as well as their relation with the large-scale atmospheric circulation. A positive trend of poleward moisture and heat transport during 1979-2018 has been identified over the Barents Sea in winter and East Siberian Sea in summer. These positive trends are attributed to an increased blocking occurrence, as quantified by a blocking track algorithm. Given the increase in poleward energy transport and its impacts on the atmospheric energy budgets, it is necessary to focus on the Arctic atmospheric rivers in more detail. Therefore, a method is developed to detect WaMAIs during December~Febrary, June~August from 1979 to 2018, and to identify the Lagrangian transformation of warm-and-moist air mass in temperature, humidity, cloud water path, surface and boundary-layer energy-budget, along the trajectories of WaMAIs. The analysis shows that WaMAIs, driven by blocking high-pressure systems over the respective ocean sectors, induce an air mass transformation in the atmospheric boundary layer, resulting in surface warming and presumably additional sea ice melt, from positive anomalies of surface net longwave irradiance and turbulent flux. In summer, from a Lagrangian perspective, the surface energy-budget anomaly decreases linearly with the downstream distance from the sea-ice edge, while total column cloud liquid water (TCLW) increases linearly. An initially stably stratified boundary layer at the ice edge transforms into a deepening well-mixed boundary layer along the trajectories, from the continuous turbulent mixing. The boundary-layer energy-budget structures are categorized into two categories: one dominated by surface turbulent mixing (TBL) ... Doctoral or Postdoctoral Thesis Arctic Barents Sea East Siberian Sea Sea ice Stockholm University: Publications (DiVA) Arctic Barents Sea East Siberian Sea ENVELOPE(166.000,166.000,74.000,74.000) |
institution |
Open Polar |
collection |
Stockholm University: Publications (DiVA) |
op_collection_id |
ftstockholmuniv |
language |
English |
topic |
Arctic Atmospheric river Stratocumulus Blocking Turbulence Longwave irradiance Meteorology and Atmospheric Sciences Meteorologi och atmosfärforskning |
spellingShingle |
Arctic Atmospheric river Stratocumulus Blocking Turbulence Longwave irradiance Meteorology and Atmospheric Sciences Meteorologi och atmosfärforskning You, Cheng Arctic Atmospheric Rivers : Eulerian and Lagrangian features, and trends over the last 40 years |
topic_facet |
Arctic Atmospheric river Stratocumulus Blocking Turbulence Longwave irradiance Meteorology and Atmospheric Sciences Meteorologi och atmosfärforskning |
description |
Arctic Atmospheric rivers, termed ‘warm-and-moist intrusion’ (WaMAI) in this thesis, transporting heat and moisture into the Arctic from lower latitudes, is a key contributor to the amplified warming in the Arctic under global change (Arctic Amplification). However, the warming effect of WaMAIs and its transformation along the trajectories into high Arctic still remain unclear, as well as their relation with the large-scale atmospheric circulation. A positive trend of poleward moisture and heat transport during 1979-2018 has been identified over the Barents Sea in winter and East Siberian Sea in summer. These positive trends are attributed to an increased blocking occurrence, as quantified by a blocking track algorithm. Given the increase in poleward energy transport and its impacts on the atmospheric energy budgets, it is necessary to focus on the Arctic atmospheric rivers in more detail. Therefore, a method is developed to detect WaMAIs during December~Febrary, June~August from 1979 to 2018, and to identify the Lagrangian transformation of warm-and-moist air mass in temperature, humidity, cloud water path, surface and boundary-layer energy-budget, along the trajectories of WaMAIs. The analysis shows that WaMAIs, driven by blocking high-pressure systems over the respective ocean sectors, induce an air mass transformation in the atmospheric boundary layer, resulting in surface warming and presumably additional sea ice melt, from positive anomalies of surface net longwave irradiance and turbulent flux. In summer, from a Lagrangian perspective, the surface energy-budget anomaly decreases linearly with the downstream distance from the sea-ice edge, while total column cloud liquid water (TCLW) increases linearly. An initially stably stratified boundary layer at the ice edge transforms into a deepening well-mixed boundary layer along the trajectories, from the continuous turbulent mixing. The boundary-layer energy-budget structures are categorized into two categories: one dominated by surface turbulent mixing (TBL) ... |
format |
Doctoral or Postdoctoral Thesis |
author |
You, Cheng |
author_facet |
You, Cheng |
author_sort |
You, Cheng |
title |
Arctic Atmospheric Rivers : Eulerian and Lagrangian features, and trends over the last 40 years |
title_short |
Arctic Atmospheric Rivers : Eulerian and Lagrangian features, and trends over the last 40 years |
title_full |
Arctic Atmospheric Rivers : Eulerian and Lagrangian features, and trends over the last 40 years |
title_fullStr |
Arctic Atmospheric Rivers : Eulerian and Lagrangian features, and trends over the last 40 years |
title_full_unstemmed |
Arctic Atmospheric Rivers : Eulerian and Lagrangian features, and trends over the last 40 years |
title_sort |
arctic atmospheric rivers : eulerian and lagrangian features, and trends over the last 40 years |
publisher |
Stockholms universitet, Meteorologiska institutionen (MISU) |
publishDate |
2021 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-198079 |
long_lat |
ENVELOPE(166.000,166.000,74.000,74.000) |
geographic |
Arctic Barents Sea East Siberian Sea |
geographic_facet |
Arctic Barents Sea East Siberian Sea |
genre |
Arctic Barents Sea East Siberian Sea Sea ice |
genre_facet |
Arctic Barents Sea East Siberian Sea Sea ice |
op_relation |
http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-198079 urn:isbn:978-91-7911-672-9 urn:isbn:978-91-7911-673-6 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766309862523797504 |