ROM SAF Commercial NRT Level 2 profile radio occultation products - Multimission

The ROM SAF Commercial NRT profile products are derived from measurements by Radio Occultation (RO) instruments based on the following satellite and input data sets: EUMETSAT-procured Spire data, NOAA-procured Spire data, NOAA-procured PlanetiQ data. The RO technique utilizes the bending due to refraction of GNSS radio signals as they pass through the Earth's atmosphere. Each occultation event gives a vertical profile of atmospheric refractivity, from which temperature, pressure, and humidity are retrieved. The data have a global coverage and are insensitive to clouds and the underlying surface. The Commercial RO NRT Level 2 profile products include the following geophysical variables: refractivity (GRM-210, GRM-220), dry temperature (GRM-215, GRM-225), obtained in the so-called 'dry' approximation, temperature (GRM-211, GRM-221), specific humidity (GRM-212, GRM-222), pressure (GRM-213, GRM-223), surface pressure (GRM-214, GRM-224), obtained by so-called 1D variational retrieval using ECMWF NWP background model data as a priori