Met Office Unified Model and CloudNet

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Met Office Unified Model and CloudNet

• Damian Wilson
• Met Office, Hadley Centre

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Current Status

• Archiving from the UM mesoscale model is
  occurring for the three observation sites.
• New Dynamics version of the Unified Model is
  scheduled to go operational on 18th June 2002.

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The diagnostic cloud scheme
Then we can diagnose the cloud fraction and water
content
If we know about the shape of the distribution of
moisture minus saturation (ql - qsat) about its
mean
Cloudy
s
s Qc
A diagnostic function is used for ice.
And the mean state of the gridbox
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Model microphysics
Part of cloud scheme
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Development of the Unified Model and CloudNet.

• New microphysics module available. This is being
  used in the latest climate model development.
• Development work on clouds is concentrating on a
  prognostic based cloud scheme.
• Currently, a prototype scheme exists but the
  scheme will not be available for operational
  trials until November 2003.
• The description of ice particle size
  distributions is being investigated using
  detailed microphysical bin-models.