EU-Confidence Case data Relevant questions

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Relevant questions

During the test phase with the Easy case, several questions popped up on the different meteorlogical parameters.

Mixing level height

The mixing level height can reach values that are very high for dispersion modelling. In the ensemble data we have limited the value to 1500m.

Roughness length

The roughness length is not included in the standard Harmonie output. We extracted a roughness-length field (times g) from one of the analyses. Over land this can be used throughout the period. Over sea the roughness length depends on the sea state, but as the plumes will not go over sea, we propose to use this fixed field anyway.

Surface height

Some of the models also need the surface height. We extracted a fixed geopotential height field (surface height times g) and included this in the ensemble data.
Over sea the same considerations hold as for the roughness length.


The precipitation fields are given in kg/m² for the surface parameters, and kg/kg (kg water per kg air) for the model level parameters. The model level parameters are logarithmic.
Hans de Vries, October 22, 2018