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IFS cycle 38r2 increases the vertical resolution of the model throughout the troposphere and stratosphere. It enables a better representation of physical processes, clouds, inversions and vertically propagating gravity waves, for example. The forecast impact in terms of objective verification scores against observations and analyses are summarised in the score card.
Upper-air verification scores
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New model level definitions are available for L137.
See correspondence between the L91 and L137 model levels is available here.
Changes to the GRIB data
The L137 model level data cannot be converted back to GRIB edition 1 due to limitations in the GRIB vertical coordinate table. See Cycle 37r2 Detail for further information about GRIB edition.
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The increase in the number of vertical levels from 91 to 137 in the high-resolution forecast model is reflected in changes to the GRIB headers, specifically the GRIB 2 Section 4 "Product definition section":
Changes to GRIB headers affecting all fields
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