HR: 14:25h
AN: B33D-04    [Abstracts]
TI: Analysis of the VIIRS Land Surface Temperature Algorithm Using MODIS Data
AU: * Yu, Y
EM: yyu@pop900.gsfc.nasa.gov
AF: George Mason University, NASA­_s GSFC, Code 923,, Greenbelt, MD 20771 United States
AU: Privette, J L
EM: jeff.privette@nasa.gov
AF: NASA­_s GSFC, NASA­_s GSFC, Code 923, Greenbelt, MD 20771 United States
AU: Pinheiro, A C
EM: ana@hsb.gsfc.nasa.gov
AF: National Research Council Postdoctoral Associate, NASA­_s GSFC, Code 974, Greenbelt, MD 20771 United States
AB: The Visible Infrared Imaging Radiometer Suite (VIIRS) is scheduled to replace AVHRR as the nation's polar orbiting wide swath sensor beginning in late 2006 with the launch of the NPOESS Preparatory Project (NPP). Following in the footsteps of EOS MODIS, VIIRS data will be used to generate multiple land products in near-real time. The current baseline VIIRS Land Surface temperature (LST) algorithms, 2- and 4-band variants of the traditional "split window" LST method, were developed by the VIIRS sensor vendor (private industry). In this article, we evaluate these algorithms using MODIS data. Split-window coefficients are derived using the MODTRAN radiative transfer model and a large set of atmospheric profiles derived from radiosondes and TIROS Operational Vertical Sounder (TOVS) data. Fourteen surface emissivity spectral data sets are used to derive the coefficients for the IGBP 17 surface types. Tests of LST uncertainty with 50 MODIS granules consistently indicate that the 2-band split window algorithm is significantly more precise than is the 4-band "dual-split window" algorithm both in daytime and nighttime, and the nighttime algorithm is more precise than the daytime algorithm. In fact, our results suggest that an LST product derived from the dual split window algorithm would exceed NPOESS LST precision specification (0.5 K). Results from the split window algorithm are closer to that specification. Based on these results, we recommend that the dual-split window algorithm be eliminated from consideration, and that the 2-band split window algorithm become the VIIRS baseline operational algorithm for all land cover types and conditions.
DE: 3322 Land/atmosphere interactions
DE: 3359 Radiative processes
DE: 3307 Boundary layer processes
DE: 1640 Remote sensing
DE: 0315 Biosphere/atmosphere interactions
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting