HR: 1340h
AN: GP33C-1443 INVITED    [Abstracts]
TI: Where do we stand on identifying motional ocean induction signals in satellite magnetic data?
AU: * Maus, S
EM: stefan.maus@noaa.gov
AF: CIRES, University of Colorado, UCB16, Boulder, CO 80309, United States
AU: * Maus, S
EM: stefan.maus@noaa.gov
AF: NOAA/NGDC, 325 Broadway, Boulder, CO 80305, United States
AB: After the successful identification and mapping of the M2 ocean tidal signal in CHAMP magnetic field measurements in 2002, no further significant progress has been reported in inferring motional ocean induction signals from satellite data. Apart from the necessity to resolve remaining disagreements between model predictions and observations of the M2 tidal signal, the next important step is to find evidence of non-tidal ocean flow signals. Unfortunately, the steady ocean circulation signal is practically indistinguishable from the crustal magnetic field. Efforts have therefore concentrated on identifying signals of annual and semi-annual variations in ocean currents. Model simulations indicate that these signals have amplitudes of the order of only 0.1 nT at satellite altitude. In an unpublished study in 2004, these signals were found to be masked in CHAMP residuals by noise levels of around 0.5nT. With advances in field modeling and the decreasing altitude of the CHAMP satellite under solar minimum conditions, it should be worthwhile to make another attempt at identifying these small signals.
UR: http://geomag.org
DE: 1515 Geomagnetic induction
DE: 1541 Satellite magnetics: main field, crustal field, external field
DE: 1545 Spatial variations: all harmonics and anomalies
DE: 4262 Ocean observing systems
DE: 4294 Instruments and techniques
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2007 Fall Meeting