CPP-08. Building Trusted Satellite Passive Microwave Data Sets: New Advancements in Calibrated, Enhanced-Resolution Brightness Temperatures for Cryospheric Applications

Abstract
Since 1978, the satellite passive microwave data record has been a mainstay of remote sensing of the cryosphere, providing twice-daily, all-weather, near-global spatial coverage for monitoring changes in cryospheric parameters. This global, gridded data set is a fundamental tool in studying surprisingly rapid cryospheric change in the satellite era. Used to analyze geophysical parameters including sea ice concentration and motion, snow water equivalent, snow- and ice-surface melt onset, and most recently, ice sheet firn aquifer extent and volume, this satellite record is a fundamental community resource for the international cryospheric research community. Due to computational and data volume limits, historical versions of the gridded passive microwave data sets were produced at coarse (25 km) spatial resolutions, using relatively simple averaging methods. In the spirit of FAIR data concepts, the Calibrated, Enhanced-Resolution Brightness Temperature (CETB) Earth System Data Record (ESDR) leverages the EASE-Grid 2.0 definition, self-describing data content and provenance conventions, machine-readable geolocation, and transparency in data processing parameters. Using the radiometer version of Scatterometer Image Reconstruction (rSIR), CETB data are enhancing spatial resolutions up to 3 km. The CETB yields greatest improvements to geophysical algorithms where brightness temperature gradients are large over short distances, including snow- and ice-covered areas in complex terrain, in transition zones from forested to open areas, along land-water coastline boundaries, and in regions of small lakes typical in the boreal regions. We have recently added daily, near real-time processing of currently operating sensors, (SSMIS and SMAP). We are adding AMSR2 measurements, and planning a major CETB reprocessing with newly recalibrated inputs. We present recent work quantify effective resolution enhancement using actual measurements rather than numerical simulations, which are demonstrating spatial resolution enhancements of 30-60% over conventional gridding techniques. This reliable, high quality, enhanced-resolution data set is advancing our understanding of both spatial and temporal variability in cryospheric phenomena.