Re: help with surface area calculation

From: Dennis Shea <shea_at_nyahnyahspammersnyahnyah>
Date: Sat Mar 10 2012 - 08:43:56 MST

Correction
   rmask = where(temp(nlt,nln).le.-1.8, 1, rmask)
should be
   rmask = where(temp.le.-1.8, 1, rmask)

Correction
   rmask = where(temp.gt.-1.8.and.temp(nlt,nln).le.0., 2, rmask)
should be
   rmask = where(temp.gt.-1.8.and.temp.le.0., 2, rmask)

On 3/9/12 8:22 PM, Dennis Shea wrote:
> [1] As noted, you can sum the area [TAREA] of each grid cell.
>
> [2] Further, do not use a double do loop. Use the 'where' function.
> where is an array function
>
> http://www.ncl.ucar.edu/Document/Functions/Built-in/where.shtml
>
> EG: Use
> rmask = where(temp(nlt,nln).le.-1.8, 1, rmask)
>
> and not
> if(.not.ismissing(temp(nlt,nln)).and.temp(nlt,nln).le.-1.8) then
> rmask(nlt,nln) = 1
>
> --
> Use
> rmask = where(temp.gt.-1.8.and.temp(nlt,nln).le.0., 2, rmask)
> Not
>
> if(.not.ismissing(temp(nlt,nln)).and.temp(nlt,nln).gt.-1.8.and.temp(nlt,nln).le.0.)
> then
> rmask(nlt,nln) = 2
> --
>
> You may want
>
> rmask = ocn->REGION_MASK
>
> rmask = rmask@_FillValue ; set all to _FillValue
>
> Then set your mask; then sum the TAREA fir eacj mask value
>
> Good luck
>
>
>
> On 3/9/12 8:05 PM, klindsay@ucar.edu wrote:
>> Angie,
>>
>> Based on the variable names you are reading from localfile, it seems
>> like you are
>> dealing with model output from the ocean model POP. The variable TAREA
>> in the model
>> output contains the surface area of each grid cell, computed in a way
>> that is
>> consistent with the model discretizations.
>>
>> Hope this helps,
>> Keith
>>
>>
>>
>>
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Received on Sat Mar 10 05:44:05 2012

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