The purpose of the Product Definition section is to describe the nature of the data contained in the Data section.
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Now there are other kinds of product groups which follow this pattern. Let's look at the atmospheric chemical constituents:
| Chemical | Deterministic | Ensemble |
|---|---|---|
| Instantaneous | 40 | 41 |
| Interval-based | 42 | 43 |
For meaning of codes, see http://apps.ecmwf.int/codes/grib/format/grib2/templates/4/
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