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Data model for the Met Office UKV 2km deterministic forecast in GRIB2 edition 2
      format. Each GRIB2 file is a concatenation of self-describing messages. Each message
      encodes one parameter, one vertical level and one forecast timestep across the
      Lambert Azimuthal Equal Area 2km grid covering the UK and near-continent.

Data Catalogue

GRIB2 section 5. Specifies the packing algorithm and parameters
needed to decode the binary grid values in section 7.
Packing type, bit depth and scale factors are defined here.

Data representation

GRIB2 section 7. The packed binary array of grid-point values.
Length = Ni × Nj values, unpacked using the scale factors from
section 5. Each value corresponds to one grid point in the
spatial grid defined by section 3.

Data values

A single GRIB2 message (one entry in the concatenated binary file).
        Each message is fully self-describing and encodes exactly one
        parameter at one vertical level for one forecast timestep.
        Sections 0-5 are metadata; section 6 is a bitmap (optional);
        section 7 contains the packed grid-point data values.

GRIB2 message

GRIB2 section 3. Defines the spatial grid geometry. UKV uses
          Grid Definition Template 3.140 (Lambert Azimuthal Equal Area projection)
          on a uniform 2km grid covering the UK and near-continent.

Grid definition

GRIB2 sections 0 and 1. Section 0 is the indicator section containing
          the discipline and edition number. Section 1 identifies the originating
          centre, reference time and significance of reference time.

Identification

Met Office local parameter extensions. Parameters with codes in the
Met Office local table (reference.metoffice.gov.uk/grib/grib2/mo--74/4.2)
that are not yet assigned a WMO standard code.

MO local parameter

Identifies the meteorological quantity being encoded. The WMO code
(discipline + parameterCategory + parameterNumber) is the primary key,
cross-referenced to CF Convention standard names and NERC vocabulary URIs
as carried in the MetDMS themes[scheme=codeflag/4.2] array.

Parameter

GRIB2 section 4. Describes what the data represents: which meteorological
          parameter, at which vertical level, and for which forecast lead time.
          UKV uses Product Definition Template 4.1 (ensemble) and 4.0 (deterministic).

Product definition

Defines the vertical coordinate to which the field applies.
UKV provides data on model height levels (metres above ground),
pressure levels (hPa) and ground/surface level.
Corresponds to MetDMS additionalExtents.vertical and additionalExtents.pressureLevels.

UKV GRIB2

Documentation

Origin