Microwave Integrated Retrieval System (MiRS) Retrieval Products From Recalibrated TROPICS TMS Data

The Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS) mission is dedicated to studies of tropospheric thermodynamics and storm lifecycles over the tropics. The Pathfinder (TROPICS-01) was launched in June 2021 and the following TROPICS series (TROPICS-03, 05, 06, and 07) were then launched in 2023. The mission includes an instrument, TROPICS Millimeter-wave Sounder (TMS) with F-band (118 GHz) oxygen absorption channels and G-band (183 GHz) water vapor absorption channels, 89 GHz for precipitation observations, and 205 GHz for cloud ice observations. Many studies have revealed promising results using the TMS measurements. In previously reported work [could cite John’s RSE paper here], the NOAA Microwave Integrated Retrieval System (MiRS) algorithm was extended to and applied to an early version of the Pathfinder TMS data.

Since their respective launches, updated calibrations have been applied to the Pathfinder TMS measurements along with updated polarization angles. These changes potentially impact several elements of MiRS, including the specification of surface emissivity a priori constraints, as well as radiometric bias and noise characterization. Therefore, in this study, we have updated components of the MiRS algorithm to accommodate the new calibration and polarization information, and used the algorithm to process a large sample of the latest TROPICS Pathfinder data. Retrieval results from the original and recalibrated TMS data will be compared, allowing an assessment of the impact of the recalibration on the retrieval products.