There is an evolving earth system science interest to capture unresolved mixing processes in both atmospheric and oceanic boundary layer modeling and in the diagnosis of these models using field…

This National Aeronautics and Space Administration (NASA) grant to the University of Washington (UW) is for the development of new remote sensing analysis techniques to produce multi-year datasets and analyses of Sentinel-1 Synthetic Aperture Radar (SAR) imagettes. The goal is to investigate atmospheric adjustment to varying ocean and atmospheric conditions, with a specific focus on air-sea flux modifications associated with organized large eddies and sub-mesoscale sea surface temperature fronts. This research aims to address unresolved mixing processes in atmospheric and oceanic boundary layer modeling and diagnosis, leveraging satellite data to support model advancements for NASA Earth system missions. The grant has a potential value of $595,377.46 and does not have a set-aside designation.

There is an evolving earth system science interest to capture unresolved mixing processes in both atmospheric and oceanic boundary layer modeling and in the diagnosis of these models using field data sets. One important example is how to include the impact of the frequently occurring organized secondary circulation in the marine atmospheric boundary layer an eddy field having scales of 1-10 KM, variable two- and three-dimensional (3D) features, and nonlocal mixing contributions that impact air-sea surface fluxes, cloud formation, and atmospheric boundary layer evolution. Another is the coupled air-sea interaction that takes place across ocean current and temperature fronts at the ocean sub-mesoscale (spatial scales of .05-5 KM), where recent focus is being given to resolving spatial wind stress variation and its impact on 3D upper ocean mixing. These differing processes share the fact that brightness contrasts in visible or radar satellite ocean imagery have been shown to delineate flow field characteristics via variable surface wave roughness that reflects the air-sea interaction. What has been lacking from a remote sensing perspective is a means to collect high-quality measurements over the global ocean and with sufficient coverage in space and time to support the needed model advancements. NASA earth system missions going forward include projects designed to resolve ocean currents, winds, and sea surface height at KM scale and this proposal seeks to apply a recent satellite synthetic aperture radar dataset to catalogue backscatter variability, with nearly global coverage, and with specific application to diagnosis of ocean-atmosphere coupling at scales inside of 5 KM. The target dataset is the wave mode 20X20 KM synthetic aperture radar imagettes of the sentinel 1A and 1B satellites. These data are designed to support ocean wave forecasting applications, as was done for the envisat mission, but the larger image size, higher radiometric quality, 5 m resolution, and vast quantity and coverage of the recorded images indicates clear potential for expanded oceanographic applications that can support both scientific and future NASA mission goals. This project will develop new remote sensing analysis techniques that will produce multi-year datasets and analyses of sentinel-1 SAR imagettes collocated with NASA satellite, buoy and weather prediction model data to investigate atmospheric adjustment to varying ocean and atmospheric conditions with specific focus on air-sea flux modifications associated with organized large eddies and with sub-mesoscale sea surface temperature fronts.