200 hPa geopotential heights

From: Michael Notaro <mnotaro_at_nyahnyahspammersnyahnyah>
Date: Wed Jun 22 2011 - 16:16:42 MDT

Does anyone see a problem with this segment of code
for computing 200 hPa geopotential heights from a regional
climate model output? The values I get seem a little bit higher
than I expected by say 100 m.

Thanks, Michael

; Assign the topography to zsfc
zsfc=new((/dimsizes(time),148,158/),float)
do it=0,dimsizes(time)-1
zsfc(it,:,:)=topo
end do
copy_VarCoords(ps,zsfc)

; Convert water vapor mixing ratio to specific humidity
q=q/(1.+q) ; mix rat to spec hum

; Use temperature and specific humidity to compute virtual temp
t=t*(1.+0.61*q)
copy_VarCoords(q,t)

sigma=a->sigma

; Get pressure at each sigma
p=pres_sigma(sigma,ps) ; hPa
copy_VarCoords(t,p)

; Compute heights
z=p(time|:,iy|:,jx|:,kz|::-1)
z=hydro(p(time|:,iy|:,jx|:,kz|::-1),t(time|:,iy|:,jx|:,kz|::-1),zsfc)
z=z(:,:,:,::-1)

; Retrieve 200 hPa heights
p1=p(time|:,iy|:,jx|:,kz|:)
h200=int2p(p1,z,200.,2)
h200_less=h200(:,:,:,0)
copy_VarCoords(ps,h200_less)

v=h200_less(iy|:,jx|:,time|:)

ctl(:,:,iy)=dim_avg_Wrap(v)

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Received on Wed Jun 22 16:17:30 2011

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