1. Intercalibration of AMSR-E and WindSat TB over Tropical Forest Scenes Thomas Meissner adapted by Marty Brewer for AMSR Science Team Meeting Huntsville, AL 2-3 June 2010

2. siteLatLonRegion 1 0 - 2N70W - 68WBrazil/Columbia 21.5N - 2.5N59W - 57WGuiana 3 3S - 020E - 23EZaire USGS Global IGBP (International Geosphere Biosphere Programme) V2 very high resolution 1/120 o maps classified as Index 2 (Evergreen Broadleaf Forest) TB averaged into 1/4 o x 1/4 o grid. All IGBP pixels within +/- 1/4 o of the grid cell center need to be classified as index 2 exclude water (Amazon) from footprint at low frequencies Calibration Sites Descending swaths only AMSR-E 1:30 am WSAT 6:00 am minimize diurnal effects Very dense canopy small ground surface effect easier to model

3. TB measured versus RTM WindSat 6.8 10.7 18.7 23.8 37.0 GHz AMSR-E 6.9 10.7 18.7 23.8 36.5 GHz Both AMSR-E 18.7 channels high: 1.7 K (v-pol), 2.2K (h-pol) WindSat 10.7 h-pol running little high (0.7 K). Previous Non-linearity correction of AMSR-E 6.9 channels looking good

4. RTM for Vegetated Land Surfaces Njoku, amended

8. RTM for Very Dense Vegetation For each calibration site: Find the scattering albedo using observed TB, and NCEP temperatures, atmospheric vapor and cloud liquid water.

9. Scattering albedo can be different at each calibration site. Frequency dependence unknown, but we assume a certain degree of spectral consistency. AMSR 18.7 GHz v/h pol outliers. Do not use for fit. Scattering Albedo

10. TB measured versus RTM WindSat 6.8 10.7 18.7 23.8 37.0 GHz AMSR-E 6.9 10.7 18.7 23.8 36.5 GHz Both AMSR-E 18.7 channels high: 1.7 K (v-pol), 2.2K (h-pol) WindSat 10.7 h-pol running little high (0.7 K). Previous Non-linearity correction of AMSR-E 6.9 channels looking good

11. Conclusions: Thomas Meissner IGARRS July 2010 Tropical rainforest scenes could (should) be used for future passive microwave radiometric calibration Additional calibration point –Especially useful if hot load is mute or unreliable Relatively simple RTM –NCEP climatology –Scattering albedo At least good consistency check for absolute radiometric calibration to ocean RTM –hot load temperature + spillover Can be used –directly (measured TB over rainforest versus RTM) –spectral intercalibration (compare different channels of same instrument) –intercalibration between different instruments. not necessary to collocate but can compare long term average. RTM takes out differences in day time, channel, EIA., …