A Climatology of the Arctic on Mid-Tropospheric Temperature Regulation
The Arctic is a unique and complex environment. Many factors play a role in determining the long-term climate of the Arctic, including mesoscale weather systems and many complex ice-albedo feedback mechanisms. Previous studies determined using real observations that although 500 hPa temperatures rea...
Main Author: | |
---|---|
Other Authors: | , , |
Format: | Thesis |
Language: | English |
Published: |
2015
|
Subjects: | |
Online Access: | http://hdl.handle.net/1969.1/153338 |
id |
fttexasamuniv:oai:repository.tamu.edu:1969.1/153338 |
---|---|
record_format |
openpolar |
spelling |
fttexasamuniv:oai:repository.tamu.edu:1969.1/153338 2023-05-15T13:11:17+02:00 A Climatology of the Arctic on Mid-Tropospheric Temperature Regulation Anthony, Jeremy Patrick Korty, Robert L North, Gerald R Frauenfeld, Oliver W 2015-02-05T17:24:34Z application/pdf http://hdl.handle.net/1969.1/153338 en eng http://hdl.handle.net/1969.1/153338 Arctic climate climatology vorticity saturation flux eddy paleoclimate troposphere atmosphere Thesis text 2015 fttexasamuniv 2015-02-07T23:24:43Z The Arctic is a unique and complex environment. Many factors play a role in determining the long-term climate of the Arctic, including mesoscale weather systems and many complex ice-albedo feedback mechanisms. Previous studies determined using real observations that although 500 hPa temperatures reach -45? by mid-November, temperatures very rarely drop below, despite a total loss of incoming solar radiation. This temperature value at 500 hPa follows moist-adiabatically to the surface value of approximately -2?, which is the freezing point of high-latitude sea water. Sea ice data was examined using satellite and model data to paint a picture of the environment during three distinct periods in history: the last glacial maximum (twenty-one thousand years ago), the mid-Holocene (six-thousand years ago), and the 20th century. Areal September minimum sea ice extent has reached record lows annually since 2007. Vertical temperature profiles created with CCSM4 model data during these three eras show the atmosphere becoming more moist-adiabatic at high latitudes over time. Saturation potential vorticity allows us to assess the convective environment, and it shows that the Arctic is becoming more tropical over time. Analysis of areal extent where temperatures fall below -45? at 500 hPa shows this to be an extremely rare occurrence, and temperatures never fall below -47.5?, except for very rare occurrences during the last glacial maximum. Transient eddy heat flux is increasing at higher latitudes, and the warm half of a cyclone contains convection (as seen in saturation potential vorticity). In this paper, we present several lines of evidence supporting a role for intermittent convection in maintaining mid-tropospheric temperatures across climate states of the past twenty-one thousand years. Thesis albedo Arctic Sea ice Texas A&M University Digital Repository Arctic |
institution |
Open Polar |
collection |
Texas A&M University Digital Repository |
op_collection_id |
fttexasamuniv |
language |
English |
topic |
Arctic climate climatology vorticity saturation flux eddy paleoclimate troposphere atmosphere |
spellingShingle |
Arctic climate climatology vorticity saturation flux eddy paleoclimate troposphere atmosphere Anthony, Jeremy Patrick A Climatology of the Arctic on Mid-Tropospheric Temperature Regulation |
topic_facet |
Arctic climate climatology vorticity saturation flux eddy paleoclimate troposphere atmosphere |
description |
The Arctic is a unique and complex environment. Many factors play a role in determining the long-term climate of the Arctic, including mesoscale weather systems and many complex ice-albedo feedback mechanisms. Previous studies determined using real observations that although 500 hPa temperatures reach -45? by mid-November, temperatures very rarely drop below, despite a total loss of incoming solar radiation. This temperature value at 500 hPa follows moist-adiabatically to the surface value of approximately -2?, which is the freezing point of high-latitude sea water. Sea ice data was examined using satellite and model data to paint a picture of the environment during three distinct periods in history: the last glacial maximum (twenty-one thousand years ago), the mid-Holocene (six-thousand years ago), and the 20th century. Areal September minimum sea ice extent has reached record lows annually since 2007. Vertical temperature profiles created with CCSM4 model data during these three eras show the atmosphere becoming more moist-adiabatic at high latitudes over time. Saturation potential vorticity allows us to assess the convective environment, and it shows that the Arctic is becoming more tropical over time. Analysis of areal extent where temperatures fall below -45? at 500 hPa shows this to be an extremely rare occurrence, and temperatures never fall below -47.5?, except for very rare occurrences during the last glacial maximum. Transient eddy heat flux is increasing at higher latitudes, and the warm half of a cyclone contains convection (as seen in saturation potential vorticity). In this paper, we present several lines of evidence supporting a role for intermittent convection in maintaining mid-tropospheric temperatures across climate states of the past twenty-one thousand years. |
author2 |
Korty, Robert L North, Gerald R Frauenfeld, Oliver W |
format |
Thesis |
author |
Anthony, Jeremy Patrick |
author_facet |
Anthony, Jeremy Patrick |
author_sort |
Anthony, Jeremy Patrick |
title |
A Climatology of the Arctic on Mid-Tropospheric Temperature Regulation |
title_short |
A Climatology of the Arctic on Mid-Tropospheric Temperature Regulation |
title_full |
A Climatology of the Arctic on Mid-Tropospheric Temperature Regulation |
title_fullStr |
A Climatology of the Arctic on Mid-Tropospheric Temperature Regulation |
title_full_unstemmed |
A Climatology of the Arctic on Mid-Tropospheric Temperature Regulation |
title_sort |
climatology of the arctic on mid-tropospheric temperature regulation |
publishDate |
2015 |
url |
http://hdl.handle.net/1969.1/153338 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
albedo Arctic Sea ice |
genre_facet |
albedo Arctic Sea ice |
op_relation |
http://hdl.handle.net/1969.1/153338 |
_version_ |
1766246719374229504 |