Tuesday, 13 January 2009
Predicted performance of NPOESS aerosol products
Hall 5 (Phoenix Convention Center)
The National Polar-orbiting Operational Environmental Satellite System (NPOESS) is being developed to replace the current NOAA Polar-orbiting Operational Environmental Satellite (POES) and the DoD Defense Meteorological Satellite Program (DMSP) systems. The instruments generally will represent significant improvements over the current operational sensors. The Visible/Infrared Imager Radiometer Suite (VIIRS) with 22 channels will be replacing the 6-channel Advanced Very High Resolution Radiometer (AVHRR) on the POES system and the 2-channel Operational Linescan System (OLS) on the DMSP system. Measurements of the atmospheric aerosols from NPOESS will come from the VIIRS instrument. The 22 VIIRS spectral bands include 16 radiometric bands plus 5 imaging bands and a day-night band. The aerosol related Environmental Data Records (EDRs) will be derived primarily from the radiometric channels covering the visible through the short-wave infrared spectral regions (412 to 2250 nm). The primary aerosol products will be the aerosol optical thickness, aerosol particle size parameter, and the identification and typing of suspended matter. These aerosol products and their derivation will be described including recent updates to the retrieval algorithms due to improved performance demonstrated by the Moderate Resolution Imaging Spectroradiometer (MODIS) collection 5 aerosol algorithm modifications. Pre-launch estimations of on-orbit performance have been derived using both proxy and synthetic data. The proxy data technique uses MODIS level 1B data to simulate the radiances which will be measured by VIIRS and compares the retrieved aerosol properties with AERONET match-up data used for MODIS aerosol product validation. The synthetic data technique uses a radiative transfer model to simulate VIIRS radiance data from a global data set and compares the retrieved aerosol properties with predefined truth.