Re: [ferret_users] Save grid area [nlon,nlat] to file?

["William S. Kessler" <william.s.kessler@xxxxxxxx>]

Isn't that what XBOX and YBOX do?

I guess you'd have to scale by cos(latitude) if your grid is in degrees.

let pi=4*atan(1)
let cell_area =  
xbox[g=gridname]*ybox[g=gridname]*cos(pi*y[gy=gridname]/180)

BK

On Sep 13, 2011, at 2:52 PM, Paul Young wrote:

> Hi all,
>
> I've seen that there are several entries in the archives about  
> saving the area for a particular region (using @din; e.g. http://www.pmel.noaa.gov/maillists/tmap/ferret_users/fu_2004/msg00026.html) 
> , but is there a simple way to return a variable that is dimensioned  
> (nlon, nlat) and has the the grid cell areas for each cell? Else, do  
> I need to step through and do the geometry myself?
>
> I'm looping through a bunch of different models (perhaps some on  
> spectral grids) and I'd like to have a generic script. I'm  
> envisaging something like:
>
> use "var_for_model_X.nc"											!Load in any variable on the  
> model grid (e.g. surface pressure: lon, lat, time)
> let cell_areas = { something clever in one/two lines! }					! 
> Calculate areas [lon,lat]
> save/file="cell_areas_for_model_X.nc" cell_areas					!Save them to  
> netcdf
>
> I bet the solution is very simple and staring me in the face, but -  
> as I can't see it - please forgive me for crowd-sourcing from the  
> help list.
>
> Cheers,
>
> Paul