NOAA Office of Satellite and Product Operations

GOES User Information and Documents

GOES-16 Product Maturity Levels (3/1/17)

The evolving calibration and validation (cal/val) maturity of the Geostationary Operational Environmental Satellite R-Series (GOES-R) products is described by three levels: Beta, Provisional, and Full validation. Once Beta Maturity of the L1b products is achieved, the Level 2+ (L2+) will progress toward Beta maturity. Further levels of maturity (Provisional and Full validation) require additional activities that can continue over a longer time period than the Beta validation process. A detailed description of the three product maturity levels is given in Table 1. The three maturity levels are:

  • Beta Validation: The product is minimally validated and may still contain significant errors; based on product quick looks using the initial calibration parameters.
  • Provisional Validation: The product performance has been demonstrated through a large, but still (seasonally or otherwise) limited, number of independent measurements. The analysis is sufficient for limited qualitative determinations of product fitness-for-purpose, and the product is potentially ready for testing operational use.
  • Full Validation: The product performance has been demonstrated over a large and wide range of representative conditions, with comprehensive documentation of product performance, including known anomalies and their remediation strategies. Products are ready for operational use.

Table 1. GOES-R Product Validation Maturity Levels.

GOES-R Product (L1b and L2+) Maturity Level
Beta Validation
Preparation Activities
  • Initial calibration applied (L1b).
  • Rapid changes in product input tables, and possibly product algorighms, can be expected.
  • Product quick looks and initial comparisons with ground truth data (if any) are not adequate to determine product quality.
  • Anomalies may be found in the product and the resolution strategy may not exist.
End state
  • Products are made available to users to gain familiarity with data formats and parameters.
  • Product has been minimally validated and may still contain significant errors.
  • Product is not optimzed for operatonal use.
Provisional Validation
Preparation Activities
  • Validation and quality assurance (QA) activities are ongoing, and the general research community is now encouraged to participate.
  • Severe algorithm anomalies are identified and under alalysis. Solutions to anomalies are in development and testing.
  • Incremental product improvements may still be occurring.
  • Users are engaged in the Customer Forums (L2+ products only), and user feedback is assessed.
End state
  • Product performance (L1 or L2+) has been demonstrated through analysis of a small number of independent measurements obtained from selected locations, periods, and associated ground-truth/field efforts.
  • Product analysis are sufficient to communicate product performance to users relative to expectations.
  • Documentation of product performance exists that includes recommended remediation strategies for all anomalies and weaknesses. Any algorithm changes associated with severe anomalies have been documented, implemented, tested, and shared with the user community.
  • Testing has been fully documented.
  • Product ready for operational use and for use in comprehensive calibration/validation activities and product optimization.
Full Validation
Preparation Activities
  • Validation, QA, and anomaly resolution activities are ongoing.
  • Incremental product improvements may still be ocurring.
  • Users are engaged and user feedback is assessed.
End state
  • Product performance for all products is defined and documented over a wide range of representative conditions via ongoing ground-truth and validation efforts.
  • Products are operationally optimized, as necessary, considering mission parameters of cost, schedule, and technical competence as compared to user expectations.
  • All known product anomalies are documented and shared with the user community.
  • Product is operational.

The assessment and declaration of a product’s maturity level is performed during the Peer Stakeholder–Product Validation Review (PS-PVR). At each PS-PVR, the status of the products will be presented by members of the cal/val science teams. For L2+ products, Beta maturity PS-PVRs are held in close proximity with and prior to Operations Handover.

Status of GOES-16 ABI L1b and CMI Data (7/7/17)

The GOES-R Peer Stakeholder - Product Validation Review for ABI L1b and CMI Provisional Maturity was held on June 1, 2017. As a result of this review, NOAA has confirmed that the ABI L1b and CMI data are at Provisional Validation Maturity as of June 1, 2017. Several remaining means of GOES-16 distribution will be activated the week of July 10-14, including additional PDA subscriptions, HRIT/EMWIN, and GEONETCast-Americas (GNC-A). Specific dates and times for data distribution through these means will be provided via separate ESPC notifications.

The ABI L1b data products are calibrated and geo-located radiances of the 16 ABI bands over the Full Disk (FD) of the Earth, the Continental United States (CONUS) region, the Mesoscale (MESO) regions, and certain instrument calibration and engineering data. The CMI data products are reflectances for bands 1-6 and brightness temperatures for bands 7-16.

Provisional validation means:

  • Validation activities are continuing and the general research community is encouraged to participate.
  • Severe algorithm anomalies are identified and under analysis. Solutions to anomalies are in development and testing.
  • Incremental product improvements may still be occurring.
  • Product performance has been demonstrated through analysis of a small number of independent measurements obtained from select locations, periods, and associated ground truth or field campaign efforts.
  • Product analysis is sufficient to establish product performance relative to expectations (performance baseline).
  • Documentation of product performance exists that includes recommended remediation strategies for all anomalies and weaknesses. Any algorithm changes associated with severe anomalies have been documented, implemented, and tested.

Users of the GOES-16 ABI L1B data bear responsibility for inspecting the data and understanding the known caveats prior to use. Below is the list of caveats that have been identified and are under analysis. Solutions are in development and testing:

  1. Navigation may have errors up to 4 km.
  2. Band-to-band co-registration errors may be up to 8 km. Larger errors occur between bands from the three groups of bands (1-6, 7-11, and 12-16 – they are in three different focal plane assemblies [FPA]).
  3. Frame-to-frame registration may be unstable, causing features to “jump” in animation.
  4. Image striping may occur across all 16 bands.
  5. Band 2 radiances are about 7% brighter than comparable polar satellite observations.
  6. The infrared (IR) radiance measurements for ABI Scan Mode 3 CONUS and MESO observations demonstrate an artificial periodicity of 15 minutes. The amplitude is uniformly small in terms of radiance but can exceed 1 K in terms of brightness temperature for cold scenes. This effect may be larger during some times of day as well as some bands.
  7. Stray light exists for Visible and Near IR (VNIR) bands approximately one hour before and after satellite local midnight during the eclipse season before the vernal (spring) equinox and after the autumnal (fall) equinox, and may exist in other days of the year. Total duration of impact is approximately twenty days twice per year. Band 7 experiences residual stray light effects during the same time frames.
  8. The VNIR band radiometric calibration may cause frequent but minor discontinuities in radiance values following each solar calibration.

For CMI, all the caveats noted above for the radiances are valid, in addition to the following:

  1. The maximum reflectance value is currently capped at 1.0 which causes dark patches within high reflectance scenes.
  2. There may be artificially cold pixels surrounding hot spots.
  3. The multiband files do not have the correct downscaling method listed in the metadata.
  4. The kappa0 value reported in the product is inconsistent with the correct kappa0 value applied to the reflectance factors.
  5. There are inconsistent data quality flag (DQF) values for off-Earth pixels.
  6. On occasion, the start time of a single band file is different from the other bands by 0.1 seconds.

Advisory on Use of GOES-16 Data Products (7/7/17)

While the GOES-16 ABI L1b and CMI data have reached provisional validation, the data from GOES-16 are still considered preliminary and are undergoing validation testing. NOAA is therefore requesting that any organizations that redistribute GOES-16 data -- before it is declared operational -- include the following disclaimer with the data:

"NOAA's GOES-16 satellite has not been declared operational and its data are preliminary and undergoing testing."

Users receiving these data through any dissemination means (including, but not limited to, PDA, GeoNetcast Americas, HRIT/EMWIN, and GOES Rebroadcast) assume all risk related to their use of GOES-16 data and NOAA disclaims any and all warranties, whether express or implied, including (without limitation) any implied warranties of merchantability or fitness for a particular purpose.

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It is expected that GOES-16 data will be declared operational, approximately 6-12 months after launch, which occurred in November 2016.

A new Sensor Processing System (SPS) software was released on 4/21/2014 for GOES-15 and 4/22/2014 for GOES-13. The new SPS release 10.4.1 replaces version 10.2 and corrects the following issues observed with GOES-13/14/15 imagers and sounders.

GOES-15 Sounder Short-Wave striping. This problem was observed during GOES-15 Post-Launch Testing (PLT) and was discovered to be due to detector-to-detector and line-to-line (East to West vs. West to East) differences. The correction algorithm corrects both problems in real-time (line by line). More detail can be found in the paper, "A Real Time De-Striping Algorithm for Geostationary Operational Environmental Satellite (GOES) P Sounder Images" by Zhenping Li, and images in the presentation "GOES15 Sounder Destriping Correction" by University of Wisconsin scientists.

GOES-13 IR Channels 2 (3.9 um) and 4 (10.7 um) registration difference was discovered to be 1 pixel or greater at certain times of day. This can cause false fog data which uses the difference between these two channels. A registration correction algorithm was developed into SPS v10.4.1 which shifts one of these channels towards the other based on whichever is closer to visible channel. When channel-2 needs correction it is shifted one full pixel whenever the difference is more than 0.5 pixel. When channel-4 needs correction (GOES-14), the data are resampled to make full correction so the two channels registration better match. More detail can be found in the paper, "GOES IR Channel to Channel Co-Registration Correction Implementation and GVAR changes" by Zhenping Li.

GOES-13 Sounder Dropped Pixel Correction: The last significant element included in this software release is the implementation of an algorithm which utilizes a second sync-bit code if the first is not found. This algorithm will allow the software to recover what was previously considered as lost data blocks which are depicted as missing pixels (black spots) since July 2013. More detail can be found in the paper, "SPS 10.4.1 Release Notes" by David Herceg.