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Title: Comparison of CYGNSS and Jason-3 Wind Speed Measurements via Gaussian Processes
Wind is a critical component of the Earth system and has unmistakable impacts on everyday life.The CYGNSS satellite mission improves observational coverage of ocean windsviaa fleet of eightmicro-satellites that use reflected GNSS signals to infer surface wind speed. We present analysescharacterizing variability in wind speed measurements among the eight CYGNSS satellites andbetween antennas, using a Gaussian process model that leverages comparisons between CYGNSSand Jason-3 during a one-year period from September 2019 to September 2020. The CYGNSS sen-sors exhibit a range of biases, mostly between1.0 m/s andþ0.2 m/s with respect to Jason-3,indicating that some CYGNSS sensors are biased with respect to one another and with respect toJason-3. The biases between the starboard and port antennas within a CYGNSS satellite aresmaller. Our results are consistent with, yet sharper than, a more traditional paired comparisonanalysis. We also explore the possibility that the bias depends on wind speed, finding some evi-dence that CYGNSS satellites have positive biases with respect to Jason-3 at low wind speeds.However, we argue that there are subtle issues associated with estimating wind speed-dependentbiases, so additional careful statistical modeling and analysis is warranted.  more » « less
Award ID(s):
1916208 1953088
PAR ID:
10485000
Author(s) / Creator(s):
;
Publisher / Repository:
Taylor and Francis
Date Published:
Journal Name:
Data Science in Science
Volume:
2
Issue:
1
ISSN:
2694-1899
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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