Many of the GPS/MET soundings fail to penetrate into the lower troposphere, which limits their use. What is the cause of this and how will the problem be addressed in future experiments such as COSMIC?
The problem has been identified as being related to the tracking firmware in the GPS receiver and inadequate antenna gain in the proof-of-concept experiment. In one of the prime-time periods of the GPS/MET experiment, changes in the tracking firmware allowed 45% of the occultations to reach to within 1 km of the surface (with the original firmware, only about 10% reached the surface). With a new GPS receiver, a higher-gain antenna, and improved firmware, we expect 90% of the soundings in the COSMIC experiment to reach to within 1 km of the surface.
Related Questions
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- Many of the GPS/MET soundings fail to penetrate into the lower troposphere, which limits their use. What is the cause of this and how will the problem be addressed in future experiments such as COSMIC?
- Many of the GPS/MET soundings appear to have a negative bias in the lower part of the sounding. What is the cause of this and how will the problem be addressed in future experiments such as COSMIC?