A study of lunar contamination and on-orbit performance of the NOAA 18 Advanced Microwave Sounding Unit-A

Computer Science – Sound

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

3

Atmospheric Composition And Structure: Instruments And Techniques, Cryosphere: Remote Sensing, Geodesy And Gravity: Ocean/Earth/Atmosphere/Hydrosphere/Cryosphere Interactions (0762, 1218, 3319, 4550)

Scientific paper

An algorithm for detection and correction of the lunar contamination in the Advanced Microwave Sounding Unit-A (AMSU-A) data is applied to study the observed lunar contamination in the NOAA 18 AMSU-A data. The algorithm is based on a physical model of the lunar surface brightness temperature and the AMSU-A antenna pattern powers to detect the lunar contamination in cold space calibration counts over a large number of scans. The algorithm performs a scan-by-scan detection and correction of the effect of lunar contamination on the AMSU-A data. It is found that the lunar contamination is significant only when the separation angle between the lunar disk and the antenna space viewing is less than 4°, beyond which no significant lunar contamination is detected, as the AMSU-A antenna power drops below 40 dB from its peak. The parameters of the AMSU-A antenna pattern powers are determined from least squares fit to the observed lunar contamination counts extracted from the cold space counts. Using the best fit parameters, we investigated the effect of the lunar contamination on the AMSU-A scene temperatures. It is found that the differences ΔTS between the near-nadir (field of view, FOV 16) scene antenna temperatures calculated with and without correction of lunar contamination vary with channels. It is about 1.5 K over ocean at channels 1 and 2 but only 0.38 K at channel 4. This trend in the ΔTS variation as a function of channels is easily understood by examining the two-point calibration equation. The results presented in this study show that the lunar contamination in the AMSU-A space calibration counts can be accurately detected and that its effect on the measured scene antenna temperatures can be corrected. The algorithm provides a practical approach for scan-by-scan correction of the lunar contamination in AMSU-A data and improves the accuracy of operational calibration of NOAA Level 1B data. An assessment of the postlaunch instrument performance is also presented.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

A study of lunar contamination and on-orbit performance of the NOAA 18 Advanced Microwave Sounding Unit-A does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A study of lunar contamination and on-orbit performance of the NOAA 18 Advanced Microwave Sounding Unit-A, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A study of lunar contamination and on-orbit performance of the NOAA 18 Advanced Microwave Sounding Unit-A will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1866994

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.