Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects
Geophysical interpretation of GRACE gravity fields has provided estimates of Antarctic ice mass change. Such analyses rely on proper consideration of ocean tidal effects through the models CSR4 and FES2004. In general, mis-modeling of tidal constituents with aliasing period less than 30 day will not...
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ftunivtasecite:oai:ecite.utas.edu.au:81984 2023-05-15T14:02:31+02:00 Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects Moore, P King, MA 2008 https://doi.org/10.1029/2007JF000871 http://ecite.utas.edu.au/81984 en eng x http://dx.doi.org/10.1029/2007JF000871 Moore, P and King, MA, Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects, Journal of Geophysical Research F: Earth Surface, 113, (2) ISSN 0148-0227 (2008) [Refereed Article] http://ecite.utas.edu.au/81984 Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified Refereed Article PeerReviewed 2008 ftunivtasecite https://doi.org/10.1029/2007JF000871 2019-12-13T21:46:56Z Geophysical interpretation of GRACE gravity fields has provided estimates of Antarctic ice mass change. Such analyses rely on proper consideration of ocean tidal effects through the models CSR4 and FES2004. In general, mis-modeling of tidal constituents with aliasing period less than 30 day will not have significant impact on ice mass change. However, for constituents, such as K1, K2, and S2, the aliasing period is sufficiently large to potentially compromise long-term variability studies. Here we quantify tidal aliasing over Antarctica by simulating GRACE signatures due to differences between CSR4 and FES2004, and the best available circum-Antarctic model, TPX06.2. The S2 simulations are in close agreement with the observed S2 signal from GRACE. Simulations of ice mass change show that over 2002-2006 long-term K1 and K2 aliasing is equivalent to a rate error of 4.5 1.3 km 3/a of ice with CSR4, but only 0.2 0.2 km 3/a with FES2004. After spatial averaging and destriping, K1 plus K2 mis-modeling in CSR4 (FES2004) introduce point-wise errors up to 5 (2) mm/a in equivalent water height over a 3.5 year period. With observed mass change equivalent to less than 30 mm/a of water height over much of Antarctica, the simulations show tidal aliasing uncertainty at the 2-3 mm/a level for August 2002-January 2006, or 10% of the signal. With GRACE Release 04, the revised estimate (April 2002-January 2006) of published ice volume decrease is 164 80 km 3 /a of ice, although this value depends very much on the GIA model and GRACE analysis approach. Copyright 2008 by the American Geophysical Union. Article in Journal/Newspaper Antarc* Antarctic Antarctica eCite UTAS (University of Tasmania) Antarctic Journal of Geophysical Research 113 F2 |
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ftunivtasecite |
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English |
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Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified |
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Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified Moore, P King, MA Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects |
topic_facet |
Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified |
description |
Geophysical interpretation of GRACE gravity fields has provided estimates of Antarctic ice mass change. Such analyses rely on proper consideration of ocean tidal effects through the models CSR4 and FES2004. In general, mis-modeling of tidal constituents with aliasing period less than 30 day will not have significant impact on ice mass change. However, for constituents, such as K1, K2, and S2, the aliasing period is sufficiently large to potentially compromise long-term variability studies. Here we quantify tidal aliasing over Antarctica by simulating GRACE signatures due to differences between CSR4 and FES2004, and the best available circum-Antarctic model, TPX06.2. The S2 simulations are in close agreement with the observed S2 signal from GRACE. Simulations of ice mass change show that over 2002-2006 long-term K1 and K2 aliasing is equivalent to a rate error of 4.5 1.3 km 3/a of ice with CSR4, but only 0.2 0.2 km 3/a with FES2004. After spatial averaging and destriping, K1 plus K2 mis-modeling in CSR4 (FES2004) introduce point-wise errors up to 5 (2) mm/a in equivalent water height over a 3.5 year period. With observed mass change equivalent to less than 30 mm/a of water height over much of Antarctica, the simulations show tidal aliasing uncertainty at the 2-3 mm/a level for August 2002-January 2006, or 10% of the signal. With GRACE Release 04, the revised estimate (April 2002-January 2006) of published ice volume decrease is 164 80 km 3 /a of ice, although this value depends very much on the GIA model and GRACE analysis approach. Copyright 2008 by the American Geophysical Union. |
format |
Article in Journal/Newspaper |
author |
Moore, P King, MA |
author_facet |
Moore, P King, MA |
author_sort |
Moore, P |
title |
Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects |
title_short |
Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects |
title_full |
Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects |
title_fullStr |
Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects |
title_full_unstemmed |
Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects |
title_sort |
antarctic ice mass balance estimates from grace: tidal aliasing effects |
publisher |
x |
publishDate |
2008 |
url |
https://doi.org/10.1029/2007JF000871 http://ecite.utas.edu.au/81984 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Antarctica |
genre_facet |
Antarc* Antarctic Antarctica |
op_relation |
http://dx.doi.org/10.1029/2007JF000871 Moore, P and King, MA, Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects, Journal of Geophysical Research F: Earth Surface, 113, (2) ISSN 0148-0227 (2008) [Refereed Article] http://ecite.utas.edu.au/81984 |
op_doi |
https://doi.org/10.1029/2007JF000871 |
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Journal of Geophysical Research |
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113 |
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F2 |
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1766272815981395968 |