Influence of Ocean–Atmosphere Interaction on the Arctic Oscillation in Two General Circulation Models
The influence of ocean–atmosphere interaction on the wintertime Arctic oscillation (AO) is investigated using a hierarchy of experiments made with two general circulation models (GCMs), ranging from climatologically forced atmospheric to fully coupled ocean–atmosphere GCMs with increasing greenhouse...
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American Meteorological Society
2001
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ftcolumbiauniv:oai:academiccommons.columbia.edu:10.7916/D88342S6 2023-05-15T14:55:45+02:00 Influence of Ocean–Atmosphere Interaction on the Arctic Oscillation in Two General Circulation Models Robertson, Andrew W. 2001 https://doi.org/10.7916/D88342S6 English eng American Meteorological Society https://doi.org/10.7916/D88342S6 Ocean-atmosphere interaction Arctic oscillation Atmosphere Articles 2001 ftcolumbiauniv https://doi.org/10.7916/D88342S6 2019-04-04T08:08:11Z The influence of ocean–atmosphere interaction on the wintertime Arctic oscillation (AO) is investigated using a hierarchy of experiments made with two general circulation models (GCMs), ranging from climatologically forced atmospheric to fully coupled ocean–atmosphere GCMs with increasing greenhouse gas concentrations. Both GCMs reproduce well the AO spatial pattern, defined by the leading hemispheric mode of monthly sea level pressure or daily 700-hPa geopotential height, although the North Pacific pole is more pronounced as compared with observations. Coupling is not found to influence this spatial pattern. Power spectra are examined for evidence of ocean–atmosphere interaction in the form of spectral reddening or significant spectral peaks. No measurable influence is found. On interannual timescales, all the model AO spectra are approximately "white," with no clear evidence of any statistically significant spectral peaks in the coupled experiments. Greenhouse gas–induced changes in sea level pressure are found to project onto the AO in one of the GCMs but not the other. On subseasonal timescales, the spectra are "red" in all the model configurations, but ocean–atmosphere interaction is not found to amplify the redness. Significant spectral peaks are found in the 15–25-day period range, consistent with observed spectra. Daily histograms of the simulated AO indices are found to be negatively skewed. A Gaussian mixture model is used to estimate the probability density function of daily hemispheric height maps, and yields three circulation regimes in both the simulations and observed data. The uncoupled atmospheric GCM simulations exhibit AO-like regimes that acquire stronger wavelike characteristics in the coupled runs. Article in Journal/Newspaper Arctic Columbia University: Academic Commons Arctic Pacific |
institution |
Open Polar |
collection |
Columbia University: Academic Commons |
op_collection_id |
ftcolumbiauniv |
language |
English |
topic |
Ocean-atmosphere interaction Arctic oscillation Atmosphere |
spellingShingle |
Ocean-atmosphere interaction Arctic oscillation Atmosphere Robertson, Andrew W. Influence of Ocean–Atmosphere Interaction on the Arctic Oscillation in Two General Circulation Models |
topic_facet |
Ocean-atmosphere interaction Arctic oscillation Atmosphere |
description |
The influence of ocean–atmosphere interaction on the wintertime Arctic oscillation (AO) is investigated using a hierarchy of experiments made with two general circulation models (GCMs), ranging from climatologically forced atmospheric to fully coupled ocean–atmosphere GCMs with increasing greenhouse gas concentrations. Both GCMs reproduce well the AO spatial pattern, defined by the leading hemispheric mode of monthly sea level pressure or daily 700-hPa geopotential height, although the North Pacific pole is more pronounced as compared with observations. Coupling is not found to influence this spatial pattern. Power spectra are examined for evidence of ocean–atmosphere interaction in the form of spectral reddening or significant spectral peaks. No measurable influence is found. On interannual timescales, all the model AO spectra are approximately "white," with no clear evidence of any statistically significant spectral peaks in the coupled experiments. Greenhouse gas–induced changes in sea level pressure are found to project onto the AO in one of the GCMs but not the other. On subseasonal timescales, the spectra are "red" in all the model configurations, but ocean–atmosphere interaction is not found to amplify the redness. Significant spectral peaks are found in the 15–25-day period range, consistent with observed spectra. Daily histograms of the simulated AO indices are found to be negatively skewed. A Gaussian mixture model is used to estimate the probability density function of daily hemispheric height maps, and yields three circulation regimes in both the simulations and observed data. The uncoupled atmospheric GCM simulations exhibit AO-like regimes that acquire stronger wavelike characteristics in the coupled runs. |
format |
Article in Journal/Newspaper |
author |
Robertson, Andrew W. |
author_facet |
Robertson, Andrew W. |
author_sort |
Robertson, Andrew W. |
title |
Influence of Ocean–Atmosphere Interaction on the Arctic Oscillation in Two General Circulation Models |
title_short |
Influence of Ocean–Atmosphere Interaction on the Arctic Oscillation in Two General Circulation Models |
title_full |
Influence of Ocean–Atmosphere Interaction on the Arctic Oscillation in Two General Circulation Models |
title_fullStr |
Influence of Ocean–Atmosphere Interaction on the Arctic Oscillation in Two General Circulation Models |
title_full_unstemmed |
Influence of Ocean–Atmosphere Interaction on the Arctic Oscillation in Two General Circulation Models |
title_sort |
influence of ocean–atmosphere interaction on the arctic oscillation in two general circulation models |
publisher |
American Meteorological Society |
publishDate |
2001 |
url |
https://doi.org/10.7916/D88342S6 |
geographic |
Arctic Pacific |
geographic_facet |
Arctic Pacific |
genre |
Arctic |
genre_facet |
Arctic |
op_relation |
https://doi.org/10.7916/D88342S6 |
op_doi |
https://doi.org/10.7916/D88342S6 |
_version_ |
1766327764979286016 |