Source/sensor: SSM/I, DMSP F-8

Coverage: August 1987-December 1988, global

Abstract: This data product contains atmospheric moisture (cloud/rain liquid water and columnar water vapor) over the ocean for a seventeen month period (1987-08-01 to 1988-12-31). The data is a level 3 product (gridded); level 2 (swath data) is available as Product #076 . The correction to cloud/rain liquid water identified by Wentz (1992) was applied to the Pathfinder data sets. A value of cloud/rain liquid water equal to or greater than 18 mg/cm2 is a qualitative indicator of rain. These parameters are calculated over water areas (plus coastal, sea ice, and possible sea ice areas) using the algorithms developed by Wentz (1989, 1992). Because Wentz cautions that parameters calculated over fresh water lakes are suspect as are those within 50-100 km of the coast, values over the open ocean or seas are the most reliable. Values over coastal, possible sea ice, and sea ice areas are calculated, but are flagged because of the questionable validity of the algorithm over these areas. The liquid water and water vapor products are stored together in a daily file, along with a browse image of each product. Non-flagged daily Pathfinder atmospheric moisture parameters were accumulated into separate 1 degree longitude and latitude rectangles for the defined period, pentads or monthly. These binned amounts were divided by the number of non-flagged good values in each bin to give the average for each rectangle. The atmospheric moisture values were also squared and summed. Bins in which no valid pixels are located are set to -10. This data product was produced and distributed by MSFC and is now archived and distributed at the JPL PO.DAAC. It is a closed data set. Frank Wentz has improved the algorithm and is currently, (as of 1996), reprocessing all SSM/I data (F-8 and F-10) to provide a new Pathfinder data set. People interested in the Pathfinder SSM/I data should also consider product #078.

Data Set Vol: 48 MB

Smallest order: Entire data set.

Std product: HDF data on 8mm tape.

Data/MediaFormats:Data are available in HDF. Data are provided on 8mm tape using LINUX Tar or via anonymous FTP to podaac.jpl.nasa.gov in the pub/atmospheric_moisture/ssmi directory.