Hi,
I have several datasets with different, non-standard polar-stereographic projections. Info from one data set is provided below.
I would like to get help in linking lon and lat with variable dimensions to extract values along a ship-track (time, lat, lon) which is irregular in time and space.
Suggestions on extracting methods are also appreciated - samplexyt is using linear interpolation and I would like to use value from the nearest data point instead.
Please let me know if you need any additional information.
Thanks,
--- Peng
The ferret show data command for one data set shows the following:
currently SET data sets:
1> ./APPx_n025_Tsurf_Cld_daily_1400.nc (default)
name title I J K L
LA Latitude 1:361 1:361 ... ...
LO Longitude 1:361 1:361 ... ...
T_SURF daily APPx Surface Temperature 1:361 1:361 ... 1:365
Both lo and la are 2-dimension arrays and are not the same for all i and j indices.
And ncdump -h gives the following:
netcdf APPx_n025_Tsurf_Cld_daily_1400 {
dimensions:
COLUMNS = 361 ;
bnds = 2 ;
ROWS = 361 ;
TIME = UNLIMITED ; // (365 currently)
variables:
double COLUMNS(COLUMNS) ;
COLUMNS:point_spacing = "even" ;
COLUMNS:axis = "X" ;
COLUMNS:bounds = "COLUMNS_bnds" ;
double COLUMNS_bnds(COLUMNS, bnds) ;
double ROWS(ROWS) ;
ROWS:point_spacing = "even" ;
ROWS:axis = "Y" ;
ROWS:bounds = "ROWS_bnds" ;
double ROWS_bnds(ROWS, bnds) ;
float LA(ROWS, COLUMNS) ;
LA:missing_value = -1.e+34f ;
LA:_FillValue = -1.e+34f ;
LA:long_name = "Latitude" ;
LA:units = "degrees_north" ;
float LO(ROWS, COLUMNS) ;
LO:missing_value = -1.e+34f ;
LO:_FillValue = -1.e+34f ;
LO:long_name = "Longitude" ;
LO:units = "degrees_east" ;
double TIME(TIME) ;
TIME:units = "day since 1997-01-01 14:00:00" ;
TIME:time_origin = "01-JAN-1997 14:00:00" ;
TIME:axis = "T" ;
TIME:bounds = "TIME_bnds" ;
double TIME_bnds(TIME, bnds) ;
float T_SURF(TIME, ROWS, COLUMNS) ;
T_SURF:missing_value = 999.9f ;
T_SURF:_FillValue = 999.9f ;
T_SURF:long_name = "daily APPx Surface Temperature (K)" ;
T_SURF:history = "From APPx_n025_All_daily_1400" ;