Re: question about satellite data

The SST data type in the file is short, you need to convert to float to get
values in the actual range. When you read the data try

f = addfile(filename,"r")
sst = short2flt(f->sst)
printMinMax(sst,1)

This should give you the values you want. The function short2flt uses the
attributes scale_factor and add_offset associated with the variable to
convert to float.

Maria


On Tue, Jul 22, 2014 at 5:50 PM, Vanúcia Schumacher <
vanucia-schumacher@hotmail.com> wrote:

> I would like to plot the values ​​corresponding to these=
 data (sst:actual_range
> = -1.8f, 35.31f ;), but when I plot the variable sst, plotting the
> range (sst:valid_range = -500s, 4000s ;
> ), why?
> How can I plot the range I need? -1.8 to 35.31
>
>
> netcdf sst.mnmean {
> dimensions:
> lat = 180 ;
> lon = 360 ;
> time = UNLIMITED ; // (391 currently)
> nbnds = 2 ;
> variables:
> float lat(lat) ;
> lat:units = "degrees_north" ;
> lat:long_name = "Latitude" ;
> lat:actual_range = 89.5f, -89.5f ;
> lat:standard_name = "latitude" ;
> lat:axis = "Y" ;
> lat:coordinate_defines = "center" ;
> float lon(lon) ;
> lon:units = "degrees_east" ;
> lon:long_name = "Longitude" ;
> lon:actual_range = 0.5f, 359.5f ;
> lon:standard_name = "longitude" ;
> lon:axis = "X" ;
> lon:coordinate_defines = "center" ;
> short sst(time, lat, lon) ;
> sst:long_name = "Monthly Mean of Sea Surface Temperature" ;
> sst:unpacked_valid_range = -5.f, 40.f ;
> sst:actual_range = -1.8f, 35.31f ;
> sst:units = "degC" ;
> sst:add_offset = 0.f ;
> sst:scale_factor = 0.01f ;
> sst:missing_value = 32767s ;
> sst:precision = 2s ;
> sst:least_significant_digit = 2s ;
> sst:var_desc = "Sea Surface Temperature" ;
> sst:dataset = "NOAA Optimum Interpolation (OI) SST V2" ;
> sst:level_desc = "Surface" ;
> sst:statistic = "Mean" ;
> sst:parent_stat = "Weekly Mean" ;
> sst:standard_name = "sea_surface_temperature" ;
> sst:cell_methods = "time: mean (monthly from weekly values interpolated=
 to
> daily)" ;
> sst:valid_range = -500s, 4000s ;
> double time(time) ;
> time:units = "days since 1800-1-1 00:00:00" ;
> time:long_name = "Time" ;
> time:actual_range = 66443., 78313. ;
> time:delta_t = "0000-01-00 00:00:00" ;
> time:avg_period = "0000-01-00 00:00:00" ;
> time:prev_avg_period = "0000-00-07 00:00:00" ;
> time:standard_name = "time" ;
> time:axis = "T" ;
> time:bounds = "time_bnds" ;
> double time_bnds(time, nbnds) ;
> time_bnds:long_name = "Time Boundaries" ;
>
> // global attributes:
> :title = "NOAA Optimum Interpolation (OI) SST V2" ;
> :Conventions = "CF-1.0" ;
> :history = "Wed Apr 6 13:47:45 2005: ncks -d time,0,278 SAVEs/
> sst.mnmean.nc sst.mnmean.nc\n",
> "Created 10/2002 by RHS" ;
> :comments = "Data described in Reynolds, R.W., N.A. Rayner, T.M.\n",
> "Smith, D.C. Stokes, and W. Wang, 2002: An Improved In Situ and
> Satellite\n",
> "SST Analysis for Climate, J. Climate" ;
> :platform = "Model" ;
> :source = "NCEP Climate Modeling Branch" ;
> :institution = "National Centers for Environmental Prediction" ;
> :references = "
> http://www.esrl.noaa.gov/psd/data/gridded/data.noaa.oisst.v2.html\n",
> "http://www.emc.ncep.noaa.gov/research/cmb/sst_analysis/" ;
> }
>
>
>
> ---
> Vanúcia Schumacher
> Mestranda em Meteorologia - UFV
> Meteorologista -UFPel
> Departamento de Meteorologia Agrícola - DEA
> Cel: (31) 9978 2522
> DEA: (31) 3899 1890
>
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>

Received on Tue Jul 22 11:58:25 2014