Three post-launch calibration methods are used to examine the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) on-orbit performance. The first method is a statistical analysis of TMI ocean observations that reveals a systematic along-scan error. The second method is an intercomparison of TMI and SSM/I observations that shows a warm bias in TMI. The last method is an analysis of TMI observations taken during TRMMs deep-space maneuver. These deep-space observations confirm both the along-scan error found from method 1 and the warm bias found from method 2. The along-scan error exhibits distinctive features having amplitudes near 1 K. The warm bias, which is related to the scene temperature, can be as large are 5 K for ocean measurements. The physical explanation of a slightly emissive main reflector is proposed to explain the calibration errors.
[1]
Gene A. Poe,et al.
Intersensor calibration of DMSP SSM/I's: F-8 to F-14, 1987-1997
,
1999,
IEEE Trans. Geosci. Remote. Sens..
[2]
C. Kummerow,et al.
The Tropical Rainfall Measuring Mission (TRMM) Sensor Package
,
1998
.
[3]
Smith,et al.
Satellite measurements of sea surface temperature through clouds
,
2000,
Science.
[4]
Principal Investigator,et al.
Algorithm Theoretical Basis Document (ATBD) AMSR Ocean Algorithm
,
1998
.
[5]
Frank J. Wentz,et al.
A Well Calibrated Ocean Algorithm for SSM/I
,
1999
.
[6]
F. Wentz.
A well‐calibrated ocean algorithm for special sensor microwave / imager
,
1997
.