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An Assessment of the Performance of ISRO’s SCATSAT-1 Scatterometer


Affiliations
1 Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015, India
2 Met Office, United Kingdom
3 Jet Propulsion Laboratory, California Institute of Technology, United States
4 CNRM, Université de Toulouse, Météo-France, CNRS, Toulouse, France
5 Royal Netherlands Meteorological Institute (KNMI), Netherlands
 

SCATSAT-1 is a continuity mission for the Oceansat-2 scatterometer, OSCAT-1, which provided useful ocean vector wind observations used in, among others, oceanography, numerical weather prediction (NWP) and nowcasting. The purpose of this paper is to review the findings of the SCATSAT-1 CalVal team regarding the stability and performance of version 1.1.3 of the SCATSAT-1 data. The international CalVal team organized by ISRO included participants from various institutions in India, ISRO’s Space Applications Centre, KNMI from the Netherlands, and from the USA, NOAA, and NASA’s JPL. To perform the evaluation, different centres processed the data independently using heritage processors and made comparisons against NASA’s Ku-band QuikSCAT mission, in situ data, and NWP models. We also provide a preliminary assessment of the impact of the SCATSAT-1 data on operational forecasts in India and Europe. We conclude that the SCATSAT-1 data shows significantly improved performance relative to ISRO’s OSCAT-1 on Oceansat-2, and that the instrument seems to be stable, given the limited period of observation. The CalVal team has also identified features in the data that could benefit from calibration and processing changes, potentially leading to further improvements on data quality.

Keywords

Calibration, OSCAT-1, QuikSCAT, Weather Prediction.
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  • An Assessment of the Performance of ISRO’s SCATSAT-1 Scatterometer

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Authors

Suchandra A. Bhowmick
Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015, India
James Cotton
Met Office, United Kingdom
Alexander Fore
Jet Propulsion Laboratory, California Institute of Technology, United States
Raj Kumar
Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015, India
Christophe Payan
CNRM, Université de Toulouse, Météo-France, CNRS, Toulouse, France
Ernesto Rodríguez
Jet Propulsion Laboratory, California Institute of Technology, United States
Anuja Sharma
Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015, India
Bryan Stiles
Jet Propulsion Laboratory, California Institute of Technology, United States
Ad Stoffelen
Royal Netherlands Meteorological Institute (KNMI), Netherlands
Anton Verhoef
Royal Netherlands Meteorological Institute (KNMI), Netherlands

Abstract


SCATSAT-1 is a continuity mission for the Oceansat-2 scatterometer, OSCAT-1, which provided useful ocean vector wind observations used in, among others, oceanography, numerical weather prediction (NWP) and nowcasting. The purpose of this paper is to review the findings of the SCATSAT-1 CalVal team regarding the stability and performance of version 1.1.3 of the SCATSAT-1 data. The international CalVal team organized by ISRO included participants from various institutions in India, ISRO’s Space Applications Centre, KNMI from the Netherlands, and from the USA, NOAA, and NASA’s JPL. To perform the evaluation, different centres processed the data independently using heritage processors and made comparisons against NASA’s Ku-band QuikSCAT mission, in situ data, and NWP models. We also provide a preliminary assessment of the impact of the SCATSAT-1 data on operational forecasts in India and Europe. We conclude that the SCATSAT-1 data shows significantly improved performance relative to ISRO’s OSCAT-1 on Oceansat-2, and that the instrument seems to be stable, given the limited period of observation. The CalVal team has also identified features in the data that could benefit from calibration and processing changes, potentially leading to further improvements on data quality.

Keywords


Calibration, OSCAT-1, QuikSCAT, Weather Prediction.

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DOI: https://doi.org/10.18520/cs%2Fv117%2Fi6%2F959-972