Humidity profile retrieval from SAPHIR on-board the Megha-Tropiques
نویسندگان
چکیده
The Megha-Tropiques (MT) satellite, a joint IndoFrench mission, was launched by ISRO’s PSLV-C18 on 12 October 2011 from Sriharikota, India. SAPHIR, a microwave humidity sounder on-board Megha Tropiques operates in six channels with frequencies around 183.31 GHz. A radiative transfer simulationbased operational algorithm has been developed to retrieve layer-averaged relative-humidity (LARH) for six atmospheric layers from the surface to nearly 12 km using SAPHIR observations over land and ocean under non-rainy conditions. SAPHIR-derived LARH for the period July to November 2012 has been validated with concurrent quality-controlled radiosonde observations as well as with ECMWF analysis data. Global validation with radiosonde and ECMWF data shows that root mean square deviation in LARH for all the six layers is nearly 20% and 15% respectively, after bias correction.
منابع مشابه
A layer-averaged relative humidity profile retrieval for microwave observations: design and results for the Megha-Tropiques payload
A statistical method trained and optimized to retrieve seven-layer relative humidity (RH) profiles is presented and evaluated with measurements from radiosondes. The method makes use of the microwave payload of the Megha-Tropiques platform, namely the SAPHIR sounder and the MADRAS imager. The approach, based on a generalized additive model (GAM), embeds both the physical and statistical charact...
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