Title

Correction of Time-Varying Radiometric Errors in TRMM Microwave Imager Calibrated Brightness Temperature Products

Authors

Authors

S. K. Biswas; K. Gopalan; W. L. Jones;S. Bilanow

Comments

Authors: contact us about adding a copy of your work at STARS@ucf.edu

Abbreviated Journal Title

IEEE Geosci. Remote Sens. Lett.

Keywords

Radiometric calibration; reflector Tb bias; Tropical Rainfall Measuring; Mission (TRMM) Microwave Imager (TMI); version 7; 1B11; Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote; Sensing; Imaging Science & Photographic Technology

Abstract

This letter presents an empirical correction for a time-varying radiometric calibration error (2.5 K peak to peak) present in the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) 1B11 calibrated brightness temperature (T(b)) data product. The T(b) error is modeled as a function of the spacecraft orbit position and the Sun elevation above the orbit plane (solar beta angle) based on the observed systematic differences between the TMI 10-GHz vertically polarized (10-V) channel oceanic T(b)'s as compared to a radiative transfer model with collocated numerical weather model environmental parameters. Assuming a slightly emissive reflector, the errors in the other TMI channels are estimated from the 10-GHz error model. This method is evaluated using before-and after-correction comparisons of 1B11 data over the ocean and Amazon, and results show that this method effectively eliminates the time-varying calibration error. This correction technique will be implemented in version 7 of the TRMM 1B11 data product, which is scheduled to be released in 2010.

Journal Title

Ieee Geoscience and Remote Sensing Letters

Volume

7

Issue/Number

4

Publication Date

1-1-2010

Document Type

Article

Language

English

First Page

851

Last Page

855

WOS Identifier

WOS:000283446700048

ISSN

1545-598X

Share

COinS