WWC snapshot of http://pegasus.nesdis.noaa.gov/tovsprod.html taken on Sat May 6 16:37:59 1995

U.S. Department of Commerce

National Oceanic and Atmospheric Administration

TOVS Path C2 Pathfinder Data Set

A sample of The NOAA Phase 1 Data Set for the Pathfinder Benchmark Period is available from NOAA's Pacific Marine Environmental Laboratory (PMEL). Click on the chart to link to PMEL, then select TOVS Path C2 under Change Data Set.

NOAA-NASA TOVS Pathfinder data products are generated from instruments flown aboard the NOAA Polar-Orbiting Operational Environmental Satellite (POES) series. In accordance with TOVS Pathfinder Science Working Groups recommendations, three distinct methodologies or "paths", each utilizing separate scientific algorithms, are used to process the High Resolution Infrared Radiation Sounder (HIRS) and Microwave Sounding Unit (MSU) data sets for the Benchmark Period. NOAA atmospheric scientists are responsible for developing and implementing algorithms for Path C2, a model-independent, a priori data-independent pathway. All paths will produce daily, five-day, and monthly composite data sets for both the morning (a.m.) and afternoon (p.m.) POES platforms.

The NOAA Path C2 TOVS reprocessing is segregated into three phases. Phase 1 provides data products derived from only the HIRS instrument while Phases 2 and 3 utilize MSU, HIRS, and AVHRR instruments to provide an expanded and enhanced set of products. Phase 1 is currently being evaluated for the Pathfinder Benchmark Period. Complete production and distribution of Phase 1 data sets will commence in the Summer of 1995. Phase 2 is scheduled to begin in March, 1995 with Benchmark Period data set production.

NOAA-developed Products

Phase 1 of the system provides three types of primary output files: master; user; and Pathfinder files using MSU Level 1b data set. There are five major processing subsystems in Phase 1: RTOVS Cloud Clearing; Path C2 Orbital; Daily Gridding/Mapping; Pentad Gridding/Mapping; and Monthly Gridding/Mapping.

The orbital processing subsystem produces brightness temperatures (BT), deep layer mean temperatures (DLMT), scan line DLMTs (SDLMT), and limb corrected brightness temperatures (LCBT). These are mapped daily into two global grids of 1 degree resolution (equal angle) for both ascending and descending orbital periods, thus yeilding daily master and user grid files. The daily totals are accumulated for a five day period for production of ascending and descending pentad master and user files. The monthly mapping subsystem uses the accumulated daily files to compute monthly averages for each grid box.

Peter J. Topoly (ptopoly@nesdis.noaa.gov) 4/19/95