>The function zonal_mpsi_Wrap will calculate the zonal mean
>stream function of atmosphere.
>I found the global zonal mean is give a good results. But when
>I do the zonal mean only in the Pacific ocean, say, between
>120E and 280E, I found the result doesn't seem right. Does
>this mean the function only calculates the global zonal
>mean streamfunction?
Yes: Notice the definition in the documentation:
/ PS
|
2 pi a cos(lat) |
ZONAL_MPSI(lev,lat) = --------------- | V(lev,lat) dp
g |
|
/ p
the [ 2 pi a ] is the circumference of the earth.
My guess is the following will work:
Let v(lev,lat,lon) and ps(lat,lon) and using coordinate subscripting:
lonE = 120.
lonW = 280.
zmpsi = zonal_mpsi(v(:,:,{lonE:lonW}),lat,p,ps(:,{lonE:lonW}))
ratio = (lonW-lonE)/360.
zmpsi = ratio*zmpsi
use the zonal_mpsi_Wrap if meta data retension is desired
http://www.ncl.ucar.edu/Document/Functions/Contributed/zonal_mpsi_Wrap.shtml
zmpsi = zonal_mpsi_Wrap(v(:,:,{lonE:lonW}),lat,p,ps(:,{lonE:lonW}))
If there is a time dimension just add the additional dim.
good luck
D
_______________________________________________
ncl-talk mailing list
ncl-talk@ucar.edu
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
This archive was generated by hypermail 2b29 : Thu Apr 21 2005 - 10:02:55 MDT