Vertical interpolation documentation? #533
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Is the algorithm UPP uses for vertical interpolation from model to pressure levels for FV3, particularly how it handles interpolating below the surface in the presence of high topography, documented somewhere? Could someone point me to it if so? |
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Replies: 2 comments
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@benjamin-cash We have no document for vertical interpolation algorithm yet. You might look into the UPP code at |
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@benjamin-cash . Vertical interpolation of all state fields from model to pressure levels is performed in linear in ln(p) fashion. .Temperature applies a constant θv computed from an average of the 2nd and 3rd model levels above ground. .Humidity fields are defined by maintaining the average RH of the 2nd and 3rd model levels above the surface. |
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@benjamin-cash
we have an old GFS tutorial ppt on UPP that described how commonly-used UPP variables are derived. It needs some
updates. Once I've made updates, I will put in on UPP wiki. To answer your questions, I extracted a few bulleted points
below:
. Vertical interpolation of all state fields from model to pressure levels is performed in linear in ln(p) fashion.
. All underground wind components are the same as those at the first model level above ground.
.Temperature applies a constant θv computed from an average of the 2nd and 3rd model levels above ground.
.Humidity fields are defined by maintaining the average RH of the 2nd and 3rd model levels above the surface.