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Sampling Errors in Monthly Rainfall Totals for TRMM and SSM/I, Based on Statistics of Retrieved Rain Rates and Simple ModelsEstimates from TRMM satellite data of monthly total rainfall over an area are subject to substantial sampling errors due to the limited number of visits to the area by the satellite during the month. Quantitative comparisons of TRMM averages with data collected by other satellites and by ground-based systems require some estimate of the size of this sampling error. A method of estimating this sampling error based on the actual statistics of the TRMM observations and on some modeling work has been developed. "Sampling error" in TRMM monthly averages is defined here relative to the monthly total a hypothetical satellite permanently stationed above the area would have reported. "Sampling error" therefore includes contributions from the random and systematic errors introduced by the satellite remote sensing system. As part of our long-term goal of providing error estimates for each grid point accessible to the TRMM instruments, sampling error estimates for TRMM based on rain retrievals from TRMM microwave (TMI) data are compared for different times of the year and different oceanic areas (to minimize changes in the statistics due to algorithmic differences over land and ocean). Changes in sampling error estimates due to changes in rain statistics due 1) to evolution of the official algorithms used to process the data, and 2) differences from other remote sensing systems such as the Defense Meteorological Satellite Program (DMSP) Special Sensor Microwave/Imager (SSM/I), are analyzed.
Document ID
20010051282
Document Type
Conference Paper
Authors
Bell, Thomas L. (NASA Goddard Space Flight Center Greenbelt, MD United States)
Kundu, Prasun K. (Emergent Information Technologies, Inc. Vienna, VA United States)
Einaudi, Franco
Date Acquired
August 20, 2013
Publication Date
January 1, 2000
Subject Category
Meteorology and Climatology
Meeting Information
AGU Fall Meeting(San Francisco, CA)
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.