Antarctic circumpolar current transport variability during 2003–05 from GRACE
Gravity Recovery and Climate Experiment ( GRACE) gravity data spanning January 2003 - November 2005 are used as proxies for ocean bottom pressure ( BP) averaged over 1 month, spherical Gaussian caps 500 km in radius, and along paths bracketing the Antarctic Circumpolar Current's various fronts....
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ftnasajpl:oai:trs.jpl.nasa.gov:2014/40844 2023-05-15T13:31:32+02:00 Antarctic circumpolar current transport variability during 2003–05 from GRACE Zlotnicki, Victor Wahr, John Fukumori, Ichiro Song, Yuhe T. 2008-06-16T21:25:17Z application/pdf http://hdl.handle.net/2014/40844 en_US eng American Meteorological Society Journal Of Physical Oceanography Volume 37, No. 2, pp. 230–244 (February 2007), doi:10.1175/JPO3009.1 06-2279 http://hdl.handle.net/2014/40844 oceanographic regions wind gravity Antarctic Circumpolar Current Article 2008 ftnasajpl https://doi.org/10.1175/JPO3009.1 2021-12-23T13:13:29Z Gravity Recovery and Climate Experiment ( GRACE) gravity data spanning January 2003 - November 2005 are used as proxies for ocean bottom pressure ( BP) averaged over 1 month, spherical Gaussian caps 500 km in radius, and along paths bracketing the Antarctic Circumpolar Current's various fronts. The GRACE BP signals are compared with those derived from the Estimating the Circulation and Climate of the Ocean ( ECCO) ocean modeling - assimilation system, and to a non-Boussinesq version of the Regional Ocean Model System ( ROMS). The discrepancy found between GRACE and the models is 1.7 cm(H2O) ( 1 cm(H2O) similar to 1 hPa), slightly lower than the 1.9 cm(H2O) estimated by the authors independently from propagation of GRACE errors. The northern signals are weak and uncorrelated among basins. The southern signals are strong, with a common seasonality. The seasonal cycle GRACE data observed in the Pacific and Indian Ocean sectors of the ACC are consistent, with annual and semiannual amplitudes of 3.6 and 0.6 cm(H2O) ( 1.1 and 0.6 cm(H2O) with ECCO), the average over the full southern path peaks ( stronger ACC) in the southern winter, on days of year 197 and 97 for the annual and semiannual components, respectively; the Atlantic Ocean annual peak is 20 days earlier. An approximate conversion factor of 3.1 Sv ( Sv equivalent to 106 m(3) s(-1)) of barotropic transport variability per cm(H2O) of BP change is estimated. Wind stress data time series from the Quick Scatterometer ( QuikSCAT), averaged monthly, zonally, and over the latitude band 40 degrees - 65 degrees S, are also constructed and subsampled at the same months as with the GRACE data. The annual and semiannual harmonics of the wind stress peak on days 198 and 82, respectively. A decreasing trend over the 3 yr is observed in the three data types. NASA/JPL Article in Journal/Newspaper Antarc* Antarctic JPL Technical Report Server Antarctic Indian Pacific The Antarctic Journal of Physical Oceanography 37 2 230 244 |
institution |
Open Polar |
collection |
JPL Technical Report Server |
op_collection_id |
ftnasajpl |
language |
English |
topic |
oceanographic regions wind gravity Antarctic Circumpolar Current |
spellingShingle |
oceanographic regions wind gravity Antarctic Circumpolar Current Zlotnicki, Victor Wahr, John Fukumori, Ichiro Song, Yuhe T. Antarctic circumpolar current transport variability during 2003–05 from GRACE |
topic_facet |
oceanographic regions wind gravity Antarctic Circumpolar Current |
description |
Gravity Recovery and Climate Experiment ( GRACE) gravity data spanning January 2003 - November 2005 are used as proxies for ocean bottom pressure ( BP) averaged over 1 month, spherical Gaussian caps 500 km in radius, and along paths bracketing the Antarctic Circumpolar Current's various fronts. The GRACE BP signals are compared with those derived from the Estimating the Circulation and Climate of the Ocean ( ECCO) ocean modeling - assimilation system, and to a non-Boussinesq version of the Regional Ocean Model System ( ROMS). The discrepancy found between GRACE and the models is 1.7 cm(H2O) ( 1 cm(H2O) similar to 1 hPa), slightly lower than the 1.9 cm(H2O) estimated by the authors independently from propagation of GRACE errors. The northern signals are weak and uncorrelated among basins. The southern signals are strong, with a common seasonality. The seasonal cycle GRACE data observed in the Pacific and Indian Ocean sectors of the ACC are consistent, with annual and semiannual amplitudes of 3.6 and 0.6 cm(H2O) ( 1.1 and 0.6 cm(H2O) with ECCO), the average over the full southern path peaks ( stronger ACC) in the southern winter, on days of year 197 and 97 for the annual and semiannual components, respectively; the Atlantic Ocean annual peak is 20 days earlier. An approximate conversion factor of 3.1 Sv ( Sv equivalent to 106 m(3) s(-1)) of barotropic transport variability per cm(H2O) of BP change is estimated. Wind stress data time series from the Quick Scatterometer ( QuikSCAT), averaged monthly, zonally, and over the latitude band 40 degrees - 65 degrees S, are also constructed and subsampled at the same months as with the GRACE data. The annual and semiannual harmonics of the wind stress peak on days 198 and 82, respectively. A decreasing trend over the 3 yr is observed in the three data types. NASA/JPL |
format |
Article in Journal/Newspaper |
author |
Zlotnicki, Victor Wahr, John Fukumori, Ichiro Song, Yuhe T. |
author_facet |
Zlotnicki, Victor Wahr, John Fukumori, Ichiro Song, Yuhe T. |
author_sort |
Zlotnicki, Victor |
title |
Antarctic circumpolar current transport variability during 2003–05 from GRACE |
title_short |
Antarctic circumpolar current transport variability during 2003–05 from GRACE |
title_full |
Antarctic circumpolar current transport variability during 2003–05 from GRACE |
title_fullStr |
Antarctic circumpolar current transport variability during 2003–05 from GRACE |
title_full_unstemmed |
Antarctic circumpolar current transport variability during 2003–05 from GRACE |
title_sort |
antarctic circumpolar current transport variability during 2003–05 from grace |
publisher |
American Meteorological Society |
publishDate |
2008 |
url |
http://hdl.handle.net/2014/40844 |
geographic |
Antarctic Indian Pacific The Antarctic |
geographic_facet |
Antarctic Indian Pacific The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
Journal Of Physical Oceanography Volume 37, No. 2, pp. 230–244 (February 2007), doi:10.1175/JPO3009.1 06-2279 http://hdl.handle.net/2014/40844 |
op_doi |
https://doi.org/10.1175/JPO3009.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
37 |
container_issue |
2 |
container_start_page |
230 |
op_container_end_page |
244 |
_version_ |
1766018663400341504 |