Topical studied on subgrid-scale dynamic processes in stably stratified geophysical flows in polar regions
The most significant changes in climate are observed in the Arctic, which is estimated to be warming at rates two to four times faster than the global average. In Antarctica, sea ice extent is experiencing a rapid decline, even faster than the decline observed in the Arctic. Therefore, the polar reg...
Main Author: | |
---|---|
Other Authors: | , , , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | English |
Published: |
Helsingin yliopisto
2024
|
Subjects: | |
Online Access: | http://hdl.handle.net/10138/576102 |
id |
ftunivhelsihelda:oai:helda.helsinki.fi:10138/576102 |
---|---|
record_format |
openpolar |
spelling |
ftunivhelsihelda:oai:helda.helsinki.fi:10138/576102 2024-06-23T07:45:47+00:00 Topical studied on subgrid-scale dynamic processes in stably stratified geophysical flows in polar regions Urbancic, Gabin Helsingin yliopisto, matemaattis-luonnontieteellinen tiedekunta Helsingfors universitet, matematisk-naturvetenskapliga fakulteten University of Helsinki, Faculty of Science van de Wiel, Bas Vihma, Timo Holtslag, Albert 2024-05-28T12:05:24Z application/pdf fulltext http://hdl.handle.net/10138/576102 eng eng Helsingin yliopisto Helsingfors universitet University of Helsinki Finnish Meteorological Institute Contributions 978-952-336-195-9 0782-6117 194 978-952-336-196-6 http://hdl.handle.net/10138/576102 URN:ISBN:978-952-336-196-6 Julkaisu on tekijänoikeussäännösten alainen. Teosta voi lukea ja tulostaa henkilökohtaista käyttöä varten. Käyttö kaupallisiin tarkoituksiin on kielletty. This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited. Publikationen är skyddad av upphovsrätten. Den får läsas och skrivas ut för personligt bruk. Användning i kommersiellt syfte är förbjuden. 111 Matematiikka 114 Fysiikka 1172 Ympäristötiede 111 Matematik 114 Fysik 1172 Miljövetenskap 111 Mathematics 114 Physical sciences 1172 Environmental sciences meteorology and Oceanography Doctoral Programme in Atmospheric Sciences Ilmakehätieteiden tohtoriohjelma Doktorandprogrammet i atmosfärvetenskap Artikkeliväitöskirja Doctoral dissertation (article-based) Artikelavhandling G5 Artikkeliväitöskirja doctoralThesis 2024 ftunivhelsihelda 2024-06-11T14:22:15Z The most significant changes in climate are observed in the Arctic, which is estimated to be warming at rates two to four times faster than the global average. In Antarctica, sea ice extent is experiencing a rapid decline, even faster than the decline observed in the Arctic. Therefore, the polar regions are highly vulnerable to the warming climate. To improve the ability of climate models to represent polar regions, a better understanding of critical physical processes is needed. This thesis focuses on the study of two subgrid-scale dynamic processes important to polar climate: submeso-scale motions in the atmospheric surface layer and internal waves in the Arctic ocean. Submeso-scale motions are important in the atmospheric surface layer during stable conditions, a common situation in polar regions due to the often negative radiative energy balance at the surface. The stable stratification creates a wave-guide for various modes of motion, each with different forcing mechanisms and properties, and each interacting uniquely with turbulence and mixing. The complexity of these motions makes the problem intractable to classical theoretical approaches. In this thesis, a novel method using autocorrelation functions is developed to characterize the occurrence and timescales of submeso-scale motions. Additionally, case study work is performed to improve the understanding of how observed submeso-scale motions interact with turbulence. Internal waves in the Arctic Ocean provide the energy needed to mix the warm Atlantic water below up to the surface, influencing the growth and melt of sea ice. This thesis addresses the dynamics and behavior of internal waves generated by tides in the region near the Yermak Plateau, a critical area as it is the last barrier before warm Atlantic water enters the Arctic Ocean. Mechanisms for internal wave propagation are demonstrated for both diurnal and semi-diurnal tides, and the conditions for the generation of internal solitary waves, which induce strong local mixing events, are ... Doctoral or Postdoctoral Thesis Antarc* Antarctica Arctic Arctic Ocean Sea ice Yermak plateau HELDA – University of Helsinki Open Repository Arctic Arctic Ocean Yermak Plateau ENVELOPE(5.000,5.000,81.250,81.250) |
institution |
Open Polar |
collection |
HELDA – University of Helsinki Open Repository |
op_collection_id |
ftunivhelsihelda |
language |
English |
topic |
111 Matematiikka 114 Fysiikka 1172 Ympäristötiede 111 Matematik 114 Fysik 1172 Miljövetenskap 111 Mathematics 114 Physical sciences 1172 Environmental sciences meteorology and Oceanography Doctoral Programme in Atmospheric Sciences Ilmakehätieteiden tohtoriohjelma Doktorandprogrammet i atmosfärvetenskap |
spellingShingle |
111 Matematiikka 114 Fysiikka 1172 Ympäristötiede 111 Matematik 114 Fysik 1172 Miljövetenskap 111 Mathematics 114 Physical sciences 1172 Environmental sciences meteorology and Oceanography Doctoral Programme in Atmospheric Sciences Ilmakehätieteiden tohtoriohjelma Doktorandprogrammet i atmosfärvetenskap Urbancic, Gabin Topical studied on subgrid-scale dynamic processes in stably stratified geophysical flows in polar regions |
topic_facet |
111 Matematiikka 114 Fysiikka 1172 Ympäristötiede 111 Matematik 114 Fysik 1172 Miljövetenskap 111 Mathematics 114 Physical sciences 1172 Environmental sciences meteorology and Oceanography Doctoral Programme in Atmospheric Sciences Ilmakehätieteiden tohtoriohjelma Doktorandprogrammet i atmosfärvetenskap |
description |
The most significant changes in climate are observed in the Arctic, which is estimated to be warming at rates two to four times faster than the global average. In Antarctica, sea ice extent is experiencing a rapid decline, even faster than the decline observed in the Arctic. Therefore, the polar regions are highly vulnerable to the warming climate. To improve the ability of climate models to represent polar regions, a better understanding of critical physical processes is needed. This thesis focuses on the study of two subgrid-scale dynamic processes important to polar climate: submeso-scale motions in the atmospheric surface layer and internal waves in the Arctic ocean. Submeso-scale motions are important in the atmospheric surface layer during stable conditions, a common situation in polar regions due to the often negative radiative energy balance at the surface. The stable stratification creates a wave-guide for various modes of motion, each with different forcing mechanisms and properties, and each interacting uniquely with turbulence and mixing. The complexity of these motions makes the problem intractable to classical theoretical approaches. In this thesis, a novel method using autocorrelation functions is developed to characterize the occurrence and timescales of submeso-scale motions. Additionally, case study work is performed to improve the understanding of how observed submeso-scale motions interact with turbulence. Internal waves in the Arctic Ocean provide the energy needed to mix the warm Atlantic water below up to the surface, influencing the growth and melt of sea ice. This thesis addresses the dynamics and behavior of internal waves generated by tides in the region near the Yermak Plateau, a critical area as it is the last barrier before warm Atlantic water enters the Arctic Ocean. Mechanisms for internal wave propagation are demonstrated for both diurnal and semi-diurnal tides, and the conditions for the generation of internal solitary waves, which induce strong local mixing events, are ... |
author2 |
Helsingin yliopisto, matemaattis-luonnontieteellinen tiedekunta Helsingfors universitet, matematisk-naturvetenskapliga fakulteten University of Helsinki, Faculty of Science van de Wiel, Bas Vihma, Timo Holtslag, Albert |
format |
Doctoral or Postdoctoral Thesis |
author |
Urbancic, Gabin |
author_facet |
Urbancic, Gabin |
author_sort |
Urbancic, Gabin |
title |
Topical studied on subgrid-scale dynamic processes in stably stratified geophysical flows in polar regions |
title_short |
Topical studied on subgrid-scale dynamic processes in stably stratified geophysical flows in polar regions |
title_full |
Topical studied on subgrid-scale dynamic processes in stably stratified geophysical flows in polar regions |
title_fullStr |
Topical studied on subgrid-scale dynamic processes in stably stratified geophysical flows in polar regions |
title_full_unstemmed |
Topical studied on subgrid-scale dynamic processes in stably stratified geophysical flows in polar regions |
title_sort |
topical studied on subgrid-scale dynamic processes in stably stratified geophysical flows in polar regions |
publisher |
Helsingin yliopisto |
publishDate |
2024 |
url |
http://hdl.handle.net/10138/576102 |
long_lat |
ENVELOPE(5.000,5.000,81.250,81.250) |
geographic |
Arctic Arctic Ocean Yermak Plateau |
geographic_facet |
Arctic Arctic Ocean Yermak Plateau |
genre |
Antarc* Antarctica Arctic Arctic Ocean Sea ice Yermak plateau |
genre_facet |
Antarc* Antarctica Arctic Arctic Ocean Sea ice Yermak plateau |
op_relation |
Finnish Meteorological Institute Contributions 978-952-336-195-9 0782-6117 194 978-952-336-196-6 http://hdl.handle.net/10138/576102 URN:ISBN:978-952-336-196-6 |
op_rights |
Julkaisu on tekijänoikeussäännösten alainen. Teosta voi lukea ja tulostaa henkilökohtaista käyttöä varten. Käyttö kaupallisiin tarkoituksiin on kielletty. This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited. Publikationen är skyddad av upphovsrätten. Den får läsas och skrivas ut för personligt bruk. Användning i kommersiellt syfte är förbjuden. |
_version_ |
1802642341749587968 |