using smos polarimetric brightness temperatures to correct for rough surface emission before...

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USING SMOS POLARIMETRIC BRIGHTNESS TEMPERATURES TO CORRECT FOR ROUGH SURFACE EMISSION BEFORE SALINITY INVERSION

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USING SMOS POLARIMETRIC BRIGHTNESS TEMPERATURES TO CORRECT FOR

ROUGH SURFACE EMISSION BEFORE SALINITY INVERSION

COMBINING HORIZONTALLY AND VERTICALLY POLARIZED BRIGHTNESS TEMPERATURES TO

REMOVE SSS DEPENDENCE

COMBINING HORIZONTALLY AND VERTICALLY POLARIZED BRIGHTNESS TEMPERATURES TO

REMOVE SSS DEPENDENCE

The relative sensitivities of horizontally and vertically polarized brightness temperatures to changes in salinity and wind speed are different at large incidence angles. We will exploit this difference to derive the wind from a linear combination of Th and Tv that is insensitive to salinity changes and then use this wind to derive salinity using the first Stokes parameter.

IMPACT OF THE METHOD ON THE ANNUAL AVERAGE SURFACE SALINITY

IMPACT OF USING SMOS-DERIVED WIND SPEED

2011 mean surface wind field from ECMWF modeling system

IMPACT OF USING SMOS-DERIVED WIND SPEED

2011 mean surface wind field derived from SMOS polarimetry. Wind speeds are lower by up to several m/s than ECMWF along the equator.

2011 Retrieved SSS – Climatology using ECMWF 10-m wind speedAscending Passes Only

IMPACT OF USING SMOS-DERIVED WIND SPEED

IMPACT OF USING SMOS-DERIVED WIND SPEED

2011 Retrieved SSS – Climatology using SMOS-derived wind speedAscending Passes Only

ZOOM ON EASTERN EQUATORIAL PACIFIC

IMPACT OF USING SMOS-DERIVED WIND SPEED

2011 mean surface wind field from ECMWF modeling system

IMPACT OF USING SMOS-DERIVED WIND SPEED

2011 mean surface wind field derived from SMOS polarimetry. Wind speeds are lower by up to several m/s than ECMWF along the equator.

IMPACT OF USING SMOS-DERIVED WIND SPEED

When ECMWF wind is used to correct for rough surface emission too much brightness is subtracted, resulting in retrieved salinity that is biased high.

IMPACT OF USING SMOS-DERIVED WIND SPEED

This bias is removed by using the wind speed derived from SMOS brightness temperatures: