Title: Microwave radiometer brightness temperature and retrieval data Location: Scottsboro Airport Site for Vortex-SE-2017 Lat/Lon: 34.68720 degN, -86.00490 degE Date updated: 30 September 2017 Contact: Dave Turner, NOAA (dave.turner@noaa.gov) DOI: 10.5065/D6639NGC System: Radiometrics MP-3000A --- Background A Radiometrics MP-3000A multi-channel microwave radiometer was integrated into CLAMPS-2. This system observes downwelling microwave radiance data (expressed as brightness temperature in units of Kelvin). These brightness temperatures span a range of frequencies from 22.0 to 58.8 GHz. From these observations, time-series of precipitable water vapor (PWV) and liquid water path (LWP) have been retrieved using the statistical method of Turner et al. (2007). The calibration of this radiometer drifted during the VORTEX-SE-2017 campaign. We also discovered that a coefficient file that contains values to account for internal temperature dependencies of various components was not properly installed by the vendor before we deployed the radiometer. Here is a short history of significant moments for this instrument during this experiment: * CLAMPS-2 deployed in Scottsboro on 24 Feb 2017 * Updated K- and V-band calibrations using LN2 data on 19 March at 1640z * Discovered that the wrong temperature-dependent factors were on radiometer; these were updated on 17 April at 2100z * Calibrated K-band using TIP data and V-band using LN2 on 17 April at 2100z * Calibrated K-band using TIP data on 2 May at 1400z * CLAMPS-2 stopped operations in Scottsboro on 3 May 2017 The drifting calibration, together with the error in the coefficient file, make the calibratio of this radiometer pretty suspect and difficult to reprocess. Thus, use the observations with care. The PWV should be accurate to within 10%, but the LWP may have errors up to 50 g/m2 or larger. --- END