STAR / SMCD / VIIRS Aerosol Calibration and Validation
VIIRS Aerosol Product Maturity Levels
The VIIRS aerosol product is undergoing a series of thorough evaluation in which the maturity level of the product is assessed. There are three maturity levels: Beta, Provisional, and Validated. The Validated level itself has four stages. The criteria for the various maturity levels are listed below.
Beta Maturity Level
- Early release product.
- Initial calibration applied.
- Minimally validated and may still contain significant errors, rapid algorithm/product changes can be expected.
- Available to allow users to gain familiarity with data formats and parameters.
- Product is not appropriate as the basis for quantitative scientific publications studies and applications.
Provisional Maturity Level
- Product quality may not be optimal.
- Performance is determined for a broader (but still limited) set of conditions.
- No requirement to demonstrate compliance with specifications.
- Incremental product improvements still occurring.
- General research community is encouraged to participate in the QA and validation of the product, but need to be aware that product validation and QA are ongoing.
- Users are urged to consult the EDR product status document prior to use of the data in publications.
- Ready for operational evaluation.
Validated Maturity Level
- Stage 1: Using a limited set of examples, the algorithm output is shown to meet the threshold performance attributes identified in the JPSS Level 1 Requirements Supplement with the exception of the S-NPP Performance Exclusions.
- Stage 2: Using a moderate set of examples, the algorithm output is shown to meet the threshold performance attributes identified in the JPSS Level 1 Requirements Supplement with the exception of the S-NPP Performance Exclusions.
- Stage 3: Using a large set of examples representing global conditions over four seasons, the algorithm output is shown to meet the threshold performance attributes identified in the JPSS Level 1 Requirements Supplement with the exception of the S-NPP Performance Exclusions.
- Stage 4: Using a large set of examples representing global conditions over four seasons, the algorithm output is shown to meet or exceed the objective performance attributes identified in the JPSS Level 1 Requirements Supplement with the exception of the S-NPP Performance Exclusions.
- For each stage the assessment includes:
- evaluation of algorithm performance to specific requirements;
- evaluation of required algorithm inputs (sensor data, ancillary data, upstream Intermediate Products and Environmental Data Records, look up table, processing coefficients table, etc.);
- error budget;
- analysis/validation of quality flags;
- input from key users;
- updated Algorithm Theoretical Basis Document (ATBD);
- updated User's Guide;
- list of known issues (both closed and outstanding).