Comparison of Saildrone and Satellite-Derived Sea Surface Temperature during Atlantic Hurricane Missions

Tropical cyclones can result in loss of life and destruction of property in coastal regions around the world. Since tropical cyclone frequency, intensity, and damages are expected to increase as a result of climate change, in situ observations of air-sea interactions and sea surface conditions within hurricanes are crucial for improving our understanding of hurricane formation and prediction. Due to the extreme conditions, measurements of sea-surface variables are historically scarce within tropical cyclones. During the 2021 and 2022 Atlantic Hurricane Seasons, several saildrone USVs from the NOAA Saildrone Hurricane Observation Missions intercepted major hurricanes including Hurricane Sam, Hurricane Fiona, and Hurricane Ian while collecting sea-surface data. One of these saildrones intercepted the eyewall of Hurricane Sam and produced the first-ever video footage of sea surface conditions within a severe tropical cyclone. Saildrone measurements from within hurricane centers provide a unique opportunity to validate satellite measurements of sea surface conditions throughout the hurricane lifecycle. In this study, the in situ sea surface temperature (SST) data was paired with the Group for High Resolution Sea Surface Temperature (GHRSST) L3C hourly sub-skin SST Gridded Satellite Product across multiple hurricanes: Sam, Fiona, and Ian using inverse distance weighting interpolation. Satellite swath SST data is also matched with the saildrone observations to include in comparisons. Discrepancies between the saildrone and satellite data and relative variations between storm and no-storm periods are assessed. These methods will also contribute to comparing saildrone observations with gridded data products and other observation platforms in future hurricane missions.