Comparison of Advanced Technology Microwave Sounder Biases Estimated Using Radio Occultation and Hurricane Florence(2018) Captured by NOAA-20 and S-NPP

The second Advanced Technology Microwave Sounder(ATMS) was onboard the National Oceanic and Atmospheric Administration(NOAA)-20 satellite when launched on 18 November 2017. Using nearly six months of the earliest NOAA-20 observations, the biases of the ATMS instrument were compared between NOAA-20 and the Suomi National PolarOrbiting Partnership(S-NPP) satellite. The biases of ATMS channels 8 to 13 were estimated from the differences between antenna temperature observations and model simulations generated from Meteorological Operational(MetOp)-A and MetOp-B satellites' Global Positioning System(GPS) radio occultation(RO) temperature and water vapor profiles. It was found that the ATMS onboard the NOAA-20 satellite has generally larger cold biases in the brightness temperature measurements at channels 8 to 13 and small standard deviations. The observations from ATMS on both S-NPP and NOAA-20 are shown to demonstrate an ability to capture a less than 1-h temporal evolution of Hurricane Florence(2018) due to the fact that the S-NPP orbits closely follow those of NOAA-20.