Using NWP Reanalysis Data for Radiometric Calibration in Electromagnetic Wave Propagation Experiments

Extensive datasets distributed by the European Centre for Medium-range Weather Forecast (ECMWF) are used to calculate retrieval coefficients for dual-channel radiometers in 14 sites spread across Europe, where databases of high-resolution RAdiosonde OBServations (RAOBSs) are available. RAOBSs are employed as the reference to assess the results obtained from ECMWF products, both in terms of single radiometric coefficients and in terms of statistics of integrated water vapor, integrated liquid water, and total atmospheric attenuation retrieved from radiometric measurements collected in one site close to Milan, Italy. The findings suggest that NWP products can be successfully used to calibrate radiometers when no appropriate RAOBS data are available.