New GRIB table entry for describing probability

[erget]

Branch

https://github.com/wmo-im/GRIB2/tree/issue-26

Summary and purpose

This document proposes a new entry to GRIB table 4.16 “Quality value associated with parameter” to describe the probability of a geophysical parameter used in Product Definition Template 4.35 “Satellite product with or without associated quality values”.

Action proposed

The meeting is requested to approve the contents for inclusion within the next update to the WMO Manual on Codes.

Discussions

Several products used at EUMETSAT provide a confidence value associated with the geophysical product. It is proposed to update GRIB table 4.16 “Quality value associated with parameter” to include “Probability” for use in Product Definition Template 4.35 “Satellite product with or without associated quality values”.

This would be used e.g. in the EUMETSAT MSG Active Fires product with Product Definition Template 4.35 in order to indicate the probability of fire observed in a given pixel of the product.

Detailed proposal

Add the following entry to GRIB Table 4.16:

Code	Name
5	Probability

[sebvi]

Hi @erget , I only have one question: will you ever need to encode a "probability of one of the other quality value" with or without threshold? For instance a probability of being within the standard deviation

[erget]

@sebvi never say never, but I don't see this anywhere on the horizon.

[chenxiaoxia2019]

@erget Hi, Daniel, a new branch for this issue has been created. Could you please check it? Thanks.

[erget]

@chenxiaoxia2019 thank you, I can see that the change to the branch is in line with the proposal. Fine from my side.

[amilan17]

SUMMARY: Add entry to Code Table 4.16.

[amilan17]

Approved by FT-2020-2.