P2.43
CLAVR Applications at NOAA/NESDIS
David R. Donahue, Science and Technology Corporation, Suitland, MD; and J. Sapper, C. Jobson, and V. Kapoor
In 2002, NESDIS began the first operational application of Clouds from the AVHRR (CLAVR). Version 1 (CLAVR-1) software received from the Office of Research and Applications (ORA) was set up to run on a development platform to process NOAA-16 data. This software reads a GAC 1B, uses a cloud mask decision tree, and outputs a “1C” file that contains the CLAVR-1 cloud mask information. The existing NOAA-KLM radiation budget software was modified to use CLAVR-1 cloud codes in determining the Earth Radiation Budget Experiment (ERBE) scene index associated with each 11x11 retrieval target of GAC pixels. Use of AMSU derived snow and ice tags was also added to improve the identification of scene type at high latitudes where some deficiencies in the CLAVR-1 algorithm exist. The software was further modified to create a second module that computes clear-sky retrievals using the CLAVR-1 cloud mask information to tag clear and cloudy GAC pixels. Post orbital gridded analysis processing bins the clear retrievals into an equal area grid and further averages them with other clear-sky fluxes in the same bin. Subtracting the clear sky from the all sky product produces a measure of cloud radiative forcing, which is important for studying climate. An improved CLAVR system, CLAVR-x, will soon be operational and replace the CLAVR-1 system. The CLAVR-x system is capable of writing cloud mask information directly back to AVHRR 1B level data records and, when operational, will provide a high-quality/high resolution cloud mask for input to any NOAA/POES product system. Images of CLAVR-1 and CLAVR-x cloud masks are displayed along with images of CLAVR-1 derived all sky and clear sky radiation budget products. The purpose of this poster is to present the current status of CLAVR applications within the NOAA/NESDIS operational environment.
Poster Session 2, IIPS Poster Session II
Wednesday, 14 January 2004, 2:30 PM-4:00 PM, Room 4AB
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