Circulation of the North Atlantic Ocean from altimetry and the Gravity Recovery and Climate Experiment geoid
Citable URI
https://hdl.handle.net/1912/3609As published
https://doi.org/10.1029/2005JC003128DOI
10.1029/2005JC003128Keyword
Ocean circulation; Geoid; Altimetry indexAbstract
We discuss the ocean circulation derived from the temporally averaged sea surface height, which is referenced to the recently released geoid from the Gravity Recovery and Climate Experiment (GRACE) mission (GRACE Gravity Model 02 (GGM02)). The creation of a precise, independent geoid allows for the calculation of the reference gravitational potential undulation surface, which is associated with the resting ocean surface height. This reference height is then removed from the temporally averaged sea surface height, leaving the dynamic ocean topography. At its most basic level the dynamic ocean topography can be related to the ocean's surface circulation through geostrophy. This has previously been impracticable because of large uncertainties in previous estimates of the Earth's geoid. Prior geoids included the temporally averaged sea surface from altimeters as a proxy for the geoid and therefore were unsuitable for calculations of the ocean's circulation. Geoid undulations are calculated from the GRACE geoid and compared to those from the NASA Goddard Space Flight Center and National Imagery and Mapping Agency Joint Earth Geopotential Model (EGM96) geoid. Error estimates are made to assess the accuracy of the new geoid. The deep ocean pressure field is also estimated by combining the calculated dynamic ocean topography with hydrography. Finally, the derived circulation is compared to independent observations of the circulation from sea surface drifters and subsurface floats. It is shown that the GGM02 geoid is significantly more accurate for use in estimating the ocean's circulation.
Description
Author Posting. © American Geophysical Union, 2006. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 111 (2006): C03005, doi:10.1029/2005JC003128.
Collections
Suggested Citation
Journal of Geophysical Research 111 (2006): C03005Related items
Showing items related by title, author, creator and subject.
-
Global observations of fine-scale ocean surface topography with the surface water and ocean topography (SWOT) mission
Morrow, Rosemary; Fu, Lee-Lueng; Ardhuin, Fabrice; Benkiran, Mounir; Chapron, Bertrand; Cosme, Emmanuel; d’Ovidio, Francesco; Farrar, J. Thomas; Gille, Sarah T.; Lapeyre, Guillaume; Le Traon, Pierre-Yves; Pascual, Ananda; Ponte, Aurélien (Frontiers Media, 2019-05-15)The future international Surface Water and Ocean Topography (SWOT) Mission, planned for launch in 2021, will make high-resolution 2D observations of sea-surface height using SAR radar interferometric techniques. SWOT will ... -
Two modes of Gulf Stream variability revealed in the last two decades of satellite altimeter data
Perez-Hernandez, M. Dolores; Joyce, Terrence M. (American Meteorological Society, 2014-01)Monthly mapped sea level anomalies (MSLAs) of the NW Atlantic in the region immediately downstream of the Gulf Stream (GS) separation point reveal a leading mode in which the path shifts approximately 100 km meridionally ... -
Observed mesoscale eddy signatures in Southern Ocean surface mixed-layer depth
Hausmann, Ute; McGillicuddy, Dennis J.; Marshall, John (John Wiley & Sons, 2017-01-27)Combining satellite altimetry with Argo profile data a systematic observational estimate of mesoscale eddy signatures in surface mixed-layer depth (MLD) is provided across the Southern Ocean (SO). Eddy composite MLD anomalies ...