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Joint Polar Satellite System

From our global observations to your local weather forecast
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Algorithm Development

The NOAA Center for Satellite Applications and Research (STAR) leads efforts to develop, test, validate and refine the science algorithms to process S-NPP and JPSS instruments data from VIIRS, CrIS, ATMS, and OMPS into user required data products such as Temperature Data Records (TDRs), Sensor Data Records (SDRs), and Environmental Data Records (EDRs). Raw Data Records (RDRs) refer to the raw data generated by sensors on the satellites. Science algorithms that perform calibration and geolocation are applied on the RDRs to produce SDRs and TDRs. EDRs are geophysical parameters derived by applying retrieval algorithms on the SDRs. EDR products provide global measurements of such quantities as sea surface temperature, ocean color, ozone and trace gases, aerosols, clouds, temperature and moisture profiles, wind speeds, land surface properties, and snow and ice cover, etc. The data products produced from the S-NPP/JPSS satellites provide continuity of critical observations for accurate weather forecasting, reliable severe storm outlooks, advanced climate diagnostics and predictions, and ocean ecosystem dynamics monitoring.

The two key components of the JPSS operational products are algorithm development and Cal-Val. All JPSS algorithms and products follow the NESDIS Satellite Products and Services Review Board (SPSRB) processes and standards. The SPSRB is responsible for the oversight and guidance necessary to effectively manage the product life cycle process from product development, transition into operations, enhancements, and retirement. The JPSS data products are evaluated using consistent validation maturity standards and the Validation Maturity Stages are defined as:

  • Product is minimally validated, and may still contain significant identified and unidentified errors.
  • Information/data from validation efforts can be used to make initial qualitative or very limited quantitative assessments regarding product fitness-for-purpose.
  • Documentation of product performance and identified product performance anomalies, including recommended remediation strategies, exists.
  • Product performance has been demonstrated through analysis of a large, but still limited (i.e., not necessarily globally or seasonally representative) number of independent measurements obtained from selected locations, time periods, or field campaign efforts.
  • Product analyses are sufficient for qualitative, and limited quantitative, determination of product fitness-for-purpose.
  • Documentation of product performance, testing involving product fixes, identified product performance anomalies, including recommended remediation strategies, exists.
  • Product is recommended for potential operational use (user decision) and in scientific publications after consulting product status documents.
  • Product performance has been demonstrated over a large and wide range of representative conditions (i.e., global, seasonal).
  • Comprehensive documentation of product performance exists that includes all known product anomalies and their recommended remediation strategies for a full range of retrieval conditions and severity level.
  • Product analyses are sufficient for full qualitative and quantitative determination of product fitness-for-purpose.
  • Product is ready for operational use based on documented validation findings and user feedback.
  • Product validation, quality assurance, and algorithm stewardship continue through the lifetime of the instrument.

If a user has a request for a new product, contact here.

The JPSS data products go through a rigorous data maturity process. The Algorithm Theoretical Basis Documents (ATBDs) provide detailed descriptions of the science algorithms, and the Cal/Val documents associated with each product provide details of the Cal/Val efforts implemented during various phases of the S-NPP Cal/Val process. All of these documents are accessible from the JSTAR document website: