Improved Aquarius Salinity Retrievals using Auxiliary Products from the CONAE Microwave Radiometer (MWR) W. Linwood Jones Central Florida Remote Sensing Lab (CFRSL) Mónica Rabolli Comision Nacional De Actividades Espaciales (CONAE) 5 th Aquarius/SAC-D Science Meeting October, 2009 Buenos Aires, Argentina

Research Objective To provide cal/val of the ocean salinity measurements provided by the Aquarius L-band radiometer/scatterometer –To develop L-band radiometric brightness temperature correction algorithms for ocean surface roughness, precipitation and sea ice concentration that are based upon MWR observations –To perform inter-satellite radiometric (brightness temperature) calibration between MWR and WindSat/TRMM Microwave Imager

CFRSL & CONAE Pre-Award Activities –MOU in progress Areas of Collaboration: –Microwave remote sensing training –MWR radiometric calibration –Geophysical algorithm development –Exchange of Personnel CONAE: 3 engineers (4 man-weeks) CFRSL Ph.D. student (5 weeks) –CFRSL Fulbright scholar MS thesis Inter-satellite radiometric calibration between MWR and WindSat Simulated MWR data derived from WindSat

Technical Status Aquarius roughness correction based on MWR MWR rain retrieval algorithm

AQ Salinity Measurement (T b ) Error Budget 37 GHz 24 GHz

AQ Scatterometer Provides Baseline Roughness Correction MWR can provide independent AQ roughness correction by retrieving surface wind speed and using L-band radiative transfer model Simon Yueh, JPL

Alternative MWR to AQ Ocean Roughness Correction RTM H-pol V-pol MWR can provide independent AQ roughness (Tb) correction by direct correlation

MWR Oceanic Rain Rate Retrieval Statistical Rain rate retrieval Based upon excess brightness temperature T rtm – radiation transfer model (NCEP input pars) Empirical Tex-RR relationship Tuned to WindSat rain rate retrievals

WindSat T meas RTM T B T ex T ex for WindSat SDR: 37GHz H-Pol kelvin

WindSat Rain Rate T ex for 37 GHz V-POL T ex for 37 GHz H-POL T ex for 23 GHz V-POL Excess-T B and SRR Relationship kelvin mm/hr kelvin

ΔT ex -IRR Relationship ΔT B, Kelvin Integrated Rain Rate, km*mm/hr 23.8 GHz V-Pol 37 GHz V-Pol 37 GHz H-Pol

Weighted Average IRR

Potential AQ Rain Rate Correction Issue Rain attenuation introduces negligible T b error However, for convective rain cells, associated ocean roughness effects may result Post-launch we will collect 3-way AQ, MWR and TRMM Precipitation Radar match-ups to assess effect

Synthetic Aperture Radar Backscatter Image of Tropical Rain Cells Scale: 25 km

Future Pre-launch Activities MWR radiometric calibration –Deliver to CONAE independent analysis of TV radiometric calibration –Deliver to CONAE post-launch radiometric calibration algorithms MWR L1/L2 simulation –Deliver forward radiation transfer model –Deliver V-0 wind speed retrieval ATBD –Deliver V-0 rain rate retrieval ATBD Develop preliminary AQ roughness correction algorithm