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Do you think if my NETCDF file has missing value flag, FERRET considers it in calculation? Could you please slightly elaborat ewhy do we need RedSea_Mask and how it is working to compute volume? I am pasting some part of ncdump -h of my data as follows:
ncdump -h tanom_1955-2004_missing_value.ncA/TANOM/ftp.nodc.noaa.gov/pub/WOD/SELECT/CDOME netcdf tanom_1955-2004_missing_value { dimensions: gsize = 2 ; lon = 360 ; nb2 = 2 ; lat = 180 ; depth = 16 ; time = UNLIMITED ; // (200 currently) variables: float lon(lon) ; lon:standard_name = "longitude" ; lon:long_name = "longitude" ; lon:units = "degrees_east" ; lon:axis = "X" ; lon:bounds = "lon_bnds" ; float lon_bnds(lon, nb2) ; float lat(lat) ; lat:standard_name = "latitude" ; lat:long_name = "latitude" ; lat:units = "degrees_north" ; lat:axis = "Y" ; lat:bounds = "lat_bnds" ; float lat_bnds(lat, nb2) ; float depth(depth) ; depth:units = "meters" ; depth:axis = "Z" ; depth:bounds = "depth_bnds" ; float depth_bnds(depth, nb2) ; double time(time) ; time:standard_name = "time" ; time:units = "months since 1955-01-01 00:00:00" ; time:calendar = "standard" ; float climatology_bounds(time, gsize) ; climatology_bounds:comment = "This variable defines the bounds of the climatological time period for each time" ; float t_an(time, depth, lat, lon) ; t_an:long_name = "Objectively Analyzed Mean" ; t_an:units = "degrees_celsius" ; t_an:comment = "Objectively analyzed climatologies are the objectively interpolated mean fields for an oceanographic variable at standard depth levels for the World Ocean." ; t_an:cell_methods = "area:mean depth:mean time:mean" ; t_an:missing_value = 9.96921e+36f ; Thanks, Mubashar From: olivier.marti@xxxxxxxxxxxx Subject: Re: [ferret_users] LEVITUS Ocean Data/FERRET shows differing results Date: Sun, 24 Mar 2013 18:44:03 +0100 To: ferret_users@xxxxxxxx; couragetoknowgc@xxxxxxxxxxx Le 24 mars 2013 à 18:24, Star Physicist a écrit : Which way I should proceed then? How could I overcome this issue? Actually there is a function in CDO for vertical averaging over all grid points called "cdo vertmean ifile ofile" but I don't know whether it can handle bottom shallower sea level. Any suggestion? You should compute a full 3D integral, not 1D/2D ou 2D/1D : USE tanom_1955-2004_missing_value.nc ! Compute a Red Sea mask. Data dependant, what do you have for missing value ? LET RedSea_mask = IF t_an GT -100 THEN 1 ! Use an ad hoc criterion, depending of your data ! Integrate temperature LET RedSea_Temp = t_an[K=1:16@DIN,x=30E:45E@DIN,y=10N:30N@DIN] ! Integrate volume LET RedSea_Vol = RedSea_mask[K=1:16@DIN,x=30E:45E@DIN,y=10N:30N@DIN] LET anom = RedSea_Temp / RedSea_Vol -- Laboratoire des Sciences du Climat et de l'Environnement Institut Pierre Simon Laplace Laboratoire CEA-CNRS-UVSQ - UMR 8212 Tel : +33 1 69 08 77 27 - Mob : +33 6 45 36 43 74 Fax : +33 1 69 08 30 73 |