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PROJECT 1 Cal/Val MODIS with S-HIS (AIRS) radiances. CAL-VAR-IO. Authors: Annamaria, Tiziana, Tiziano, Teo. MODIS / SHIS Comparisons A detailed comparison should account for: instrumental noise and scene variations Different spatial footprints
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PROJECT 1 Cal/Val MODIS with S-HIS (AIRS) radiances CAL-VAR-IO Authors: Annamaria, Tiziana, Tiziano, Teo
MODIS / SHIS Comparisons • A detailed comparison should account for: • instrumental noise and scene variations • Different spatial footprints • Different view angles (MODIS is near nadir, SHIS is ~±35deg from nadir) • Different observation altitudes (MODIS is 705km, SHIS is ~20km on ER2, ~14km on Proteus) • Different spectral response (MODIS has different channels with different bandwidth, SHIS Dn=~0.5 cm-1) and sampling
X TORPEX 2003
FOV MODIS FOV S-HIS • Average SHIS data within MODIS FOV(s) and compare
Average SHIS data within MODIS FOV(s) & compare • We convolve high resolution data with the response functions of the selected MODIS bands • Ex. of response functions of MODIS CO2 bands
MODISsim MODISobs S-HISsim S-HISobs • Compare Residuals from calculations: (obs-calc)SHIS to (obs-calc)MODIS • SHIS and MODIS calcs each done at correct altitudes, view angles, spectral resolution and sampling. • Monochromatic calcs done using same forward model,atmospheric state, and surface property inputs.
MODISsim MODISobs S-HISsim S-HISobs • Difference Residuals: Spectral Resolutions made similar
CONCLUSIONS: • MODIS-(S-HIS): • GOOD RESULTS IN THE WINDOW AND H2OVAP • EXPECTED DISAGREEMENTS IN THE CO2 AND O3 • MODIS-(S-HIS) RESIDUALS: • GOOD CORRECTION IN THE O3 BAND • SIMULATIONS WITH TOO MUCH WV AT HIGH LEVELS