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Hello,
I have two spatial data sets NDVI and Precipitation (P)
P is on a Mercator projection and NDVI on a lat, lon grid. I would like to have them both on a simple lat, lon grid.
I guess, I need to regrid P on a lat, lon grid and then regrid NDVI on the same grid.
Problem is that I do not know how to get P off the Mercator projection.... any suggestions?
Below is how P comes up in ferret and the netcdf information from opening the file in R. Weirdly ncdump did not read the precipitation file. FInally at the bottom the header of the netcdf file for NDVI
I can do a shade DAILY_RAINFALL[l=1],lon,lat
and I get P mapped on a lat, lon map, but as the dimensions for P are actually "projection_y_coordinate" and " projection_x_coordinate" given meters I don't quite know how to get the variable onto a lat lon grid.
THank you for all your thoughts, best, Joerg
yes? use ukcp09_gridded-land-obs-daily_5km_rainfall_19820101-19821231.nc
yes? show data
currently SET data sets:
1> ./ukcp09_gridded-land-obs-daily_5km_rainfall_19820101-19821231.nc (default)
name title I J K L
DAILY_RAINFALL
Daily precipitation amount 1:180 1:290 ... 1:365
TRANSVERSE_MERCATOR
... ... ... ...
LAT 1:180 1:290 ... ...
LON 1:180 1:290 ... ...
(R) ukcp09_gridded-land-obs-daily_5km_rainfall_19820101-19821231.nc (NC_FORMAT_NETCDF4):
7 variables (excluding dimension variables):
double daily_rainfall[projection_x_coordinate,projection_y_coordinate,time] (Contiguous storage)
_FillValue: 1e+20
standard_name: lwe_thickness_of_precipitation_amount
long_name: Daily precipitation amount
units: mm
cell_methods: time: sum
grid_mapping: transverse_mercator
coordinates: lat lon
int transverse_mercator[] (Contiguous storage)
grid_mapping_name: transverse_mercator
longitude_of_prime_meridian: 0
semi_major_axis: 6377563.396
semi_minor_axis: 6356256.909
longitude_of_central_meridian: -2
latitude_of_projection_origin: 49
false_easting: 4e+05
false_northing: -1e+05
scale_factor_at_central_meridian: 0.9996012717
double time_bnds[bnds,time] (Contiguous storage)
double projection_y_coordinate_bnds[bnds,projection_y_coordinate] (Contiguous storage)
double projection_x_coordinate_bnds[bnds,projection_x_coordinate] (Contiguous storage)
double lat[projection_x_coordinate,projection_y_coordinate] (Contiguous storage)
units: degrees_north
standard_name: latitude
double lon[projection_x_coordinate,projection_y_coordinate] (Contiguous storage)
units: degrees_east
standard_name: longitude
4 dimensions:
time Size:365
axis: T
bounds: time_bnds
units: hours since 1800-01-01 00:00:00
standard_name: time
calendar: standard
projection_y_coordinate Size:290
axis: Y
bounds: projection_y_coordinate_bnds
units: m
standard_name: projection_y_coordinate
projection_x_coordinate Size:180
axis: X
bounds: projection_x_coordinate_bnds
units: m
standard_name: projection_x_coordinate
bnds Size:2
netcdf ndvitest {
dimensions:
LON2017_2196 = 180 ;
LAT1657_1836 = 180 ;
TIME1 = 12 ;
variables:
double LON2017_2196(LON2017_2196) ;
LON2017_2196:point_spacing = "even" ;
LON2017_2196:axis = "X" ;
LON2017_2196:standard_name = "longitude" ;
double LAT1657_1836(LAT1657_1836) ;
LAT1657_1836:point_spacing = "even" ;
LAT1657_1836:axis = "Y" ;
LAT1657_1836:standard_name = "latitude" ;
double TIME1(TIME1) ;
TIME1:point_spacing = "even" ;
TIME1:axis = "Z" ;
TIME1:standard_name = "altitude" ;
short NDVI(TIME1, LAT1657_1836, LON2017_2196) ;
NDVI:missing_value = -5000s ;
NDVI:_FillValue = -5000s ;
NDVI:units = "1" ;
NDVI:long_name = "NDVI" ;
NDVI:history = "From ndvi3g_geo_v1_1982_0106.nc4" ;
// global attributes:
:history = "PyFerret V7.1 (optimized) 20-Nov-18" ;
:Conventions = "CF-1.6" ;
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