Re: EP-Flux near real time

The Subject 'EP-Flux near real time' is not clear.
What is meant by "near real time" ?

Eddy flux quantities are (say) u't' which require
a mean quantity (uavg, tavg). There are many EP flux forms.
The following should help you write the code.

   U(time,lev,lat,lon), T(time,lev,lat,lon)
      0 1 2 3

Say you have one month U,T at 6hrly times
--------
Without meta data

   uavg = dim_avg_n(U, 0) ; 3D
   tavg = dim_avg_n(T, 0)
   up = U-conform(U, uavg, (/1,2,3/) ) ; 4D
   tp = T-conform(T, uavg, (/1,2,3/) )
   uptp = up*tp
   uptp_avg = dim_avg_n(uptp, 0) ; 3D
--------
With meta data (recommended) and printing variable overviews

   uavg = dim_avg_n_Wrap(U, 0) ; (lev,lat,lon)
   tavg = dim_avg_n_Wrap(T, 0)
   printVarSummary(uavg)
   printVarSummary(tavg)

   up = U-conform(U, uavg, (/1,2,3/) )
   copy_VarMeta(U, up)
   up@long_name = "u'"
   printVarSummary(up) ; (time,lev,lat,lon)

   tp = ...

   uptp = up*tp
   copy_VarCoords(U, uptp)
   uptp@long_name = "u't'"
   uptp@units = "(m/s)-K"
   printVarSummary(uptp) ; (time,lev,lat,lon)

   uptp_avg = dim_avg_n_Wrap(uptp, 0)
   uttp_avg@long_name = "monthly avg u't'"
   printVarSummary(uptp_avg) ; (lev,lat,lon)

Note: **all** non-linear quantities must be computed
       **at each time step**

On 6/11/12 9:25 AM, Wilhelm Haygen wrote:
> Hi,
> Does anybody has experience in calculating/computing EP-Flux by using NCL?
> Especially based on variable U, V and T (Theta)?
> Thanks for your sharing,
>
> WH,
>
>
>
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Received on Mon Jun 11 11:17:30 2012