Studies of a Rapid Change Detector Using CYGNSS Level-2 Wind Speed Products

Abstract

This work further investigates the use of ocean wind speed retrievals from NASA's Cyclone Global Navigation Satellite System (CYGNSS) mission that are closely spaced in space and in time to detect regions in the atmosphere undergoing “rapid” change. As in a previous investigation, CYGNSS measurement “clumps” (i.e., groups of wind speed measurements satisfying specified time/space separation criteria) are used to create a wind speed change detector, and the results are compared to a set of atmospheric properties derived from Modern-Era Retrospective Analysis for Research and Applications 2 model datasets. The analysis uses a four-year CYGNSS Level-2 wind speed dataset developed by the National Oceanic and Atmospheric Administration and highlights the potential for using CYGNSS's wind speed measurements to locate various dynamic activities occurring over the ocean's surface. The presented results also highlight some of the challenges of the method, including the inherent dependence of detection performance on the quality of CYGNSS's wind speed estimates as well as the validity of comparisons to “truth” datasets having temporal resolutions much coarser than those provided by CYGNSS.

Keywords

• Bistatic radar systems
• cyclone global navigation satellite system (CYGNSS)
• global navigation satellite systems reflectometry (GNSS-R)
• ocean surface dynamics
• rough surface scattering