A study discusses a robust intercalibration technique using a well validated radiative transfer code that can be applied to the higher-frequency sounding channels for the NASA Global Precipitation Measurement (GPM) mission. Intercalibration of these high-frequency sounding channels will require good and timely estimates of the temperature and water vapor profiles. The approach will leverage results from recent improvements to spectroscopic line parameters and continuum in both the microwave and infrared regions.

The radiative transfer model (RTM) measurement comparisons have been performed for all clear-sky measurements with footprints within 8 km of the North Slope of Alaska (NSA), Southern Great Plains (SGP), and Tropical Western Pacific (TWP 1) ARM sites during 2008. Data were screened according to column water vapor in order to ensure that only cases that were insensitive to surface conditions were included. The RTM was run with two sources of input atmospheric profiles in order to assess the impact of the choice of input profiles on the double difference results.

This work was done by Jean-Luc Moncet of Atmospheric and Environmental Research (AER) and Vivienne Payne from JPL for Goddard Space Flight Center. GSC-16810-1

NASA Tech Briefs Magazine

This article first appeared in the May, 2014 issue of NASA Tech Briefs Magazine.

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