Hello,
Just to share: ESA Copernicus disseminates gridded NDVI data 47040 x
120960 derived from satellite observations.
The files are quite large relatively to a climate reanalysis file.
All in all, you can always convert a large GeoTIFF file to NetCDF
utilizng GDAL (e.g., to apply NCO or other software)
Below is the CDL output for on one of Copernicus NetCDF files.
Size is 793 MB (831,860,266 bytes)
> ncks --cdl -M --hdn c_gls_NDVI300_201601010000_GLOBE_PROBAV_V1.0.1.nc
netcdf c_gls_NDVI300_201601010000_GLOBE_PROBAV_V1.0.1 {
dimensions:
lat = 47040 ;
lon = 120960 ;
variables:
ubyte NDVI(lat,lon) ;
NDVI:_FillValue = 255ub ;
NDVI:grid_mapping = "crs" ;
NDVI:scale_factor = 0.004f ;
NDVI:missing_value = 255ub ;
NDVI:flag_meanings = "Missing cloud snow sea background" ;
NDVI:add_offset = -0.08f ;
NDVI:long_name = "Normalized Difference Vegetation Index 333M" ;
NDVI:standard_name = "normalized_difference_vegetation_index" ;
NDVI:flag_values = 251ub, 252ub, 253ub, 254ub, 255ub ;
NDVI:units = ;
NDVI:valid_range = 0ub, 250ub ;
NDVI:_Storage = "chunked" ;
NDVI:_ChunkSizes = 1272, 3270 ;
NDVI:_DeflateLevel = 4 ;
NDVI:_Shuffle = "true" ;
char crs ;
crs:long_name = "coordinate reference system" ;
crs:semi_major_axis = 6378137. ;
crs:spatial_ref = "GEOGCS[\"WGS
84\",DATUM[\"WGS_1984\",SPHEROID[\"WGS
84\",6378137,298.257223563,AUTHORITY[\"EPSG\",\"7030\"]],TOWGS84[0,0,0,0,0,0,0],AUTHORITY[\"EPSG\",\"6326\"]],PRIMEM[\"Greenwich\",0,AUTHORITY[\"EPSG\",\"8901\"]],UNIT[\"degree\",0.0174532925199433,AUTHORITY[\"EPSG\",\"9108\"]],AUTHORITY[\"EPSG\",\"4326\"]]"
;
crs:grid_mapping_name = "latitude_longitude" ;
crs:_CoordinateTransformType = "Projection" ;
crs:_CoordinateAxisTypes = "GeoX GeoY" ;
crs:inverse_flattening = 298.257223563 ;
crs:GeoTransform = "-180.0000000000 0.0029761905 0.0
80.0000000000 0.0 -0.0029761905" ;
crs:longitude_of_prime_meridian = 0. ;
double lat(lat) ;
lat:standard_name = "latitude" ;
lat:long_name = "latitude" ;
lat:DIMENSION_LABELS = "lat" ;
lat:units = "degrees_north" ;
lat:_CoordinateAxisType = "Lat" ;
lat:axis = "Y" ;
lat:_Storage = "contiguous" ;
double lon(lon) ;
lon:standard_name = "longitude" ;
lon:long_name = "longitude" ;
lon:DIMENSION_LABELS = "lon" ;
lon:units = "degrees_east" ;
lon:_CoordinateAxisType = "Lon" ;
lon:axis = "X" ;
lon:_Storage = "contiguous" ;
// global attributes:
:Conventions = "CF-1.6" ;
:parent_identifier = "urn:cgls:global:ndvi300_v1_333m" ;
:copyright = "Copernicus Service information 2016" ;
:time_coverage_end = "2016-01-10T23:59:59Z" ;
:title = "10-daily Normalized Difference Vegetation Index 333M:
GLOBE 2016-01-01T00:00:00Z" ;
:product_version = "V1.0.1" ;
:history = "Processing line NDVI: 2016-04-22" ;
:time_coverage_start = "2016-01-01T00:00:00Z" ;
:long_name = "Normalized Difference Vegetation Index" ;
:processing_mode = "Near Real Time" ;
:orbit_type = "LEO" ;
:references = "http://land.copernicus.eu/global/products/ndvi"; ;
:platform = "Proba-V" ;
:archive_facility = "VITO" ;
:identifier =
"urn:cgls:global:ndvi300_v1_333m:NDVI300_201601010000_GLOBE_PROBAV_V1.0.1"
;
:sensor = "VEGETATION" ;
:institution = "VITO NV" ;
:processing_level = "L3" ;
:source = "Derived from EO satellite imagery" ;
:_Format = "netCDF-4" ;
:_SOURCE_FORMAT = "NC_FORMAT_HDF5" ;
} // group /
2017-06-26 8:08 GMT+03:00 Ward Fisher <wfisher@xxxxxxxx>:
> Hello all,
>
> We've been asked a question regarding the largest netCDF file that we are
> aware of, in terms of a real file containing practical data. I am not aware
> of any specific single large data file "in the wild", so I thought I would
> ask the mailing list. Does anybody out there have (or is aware of) a
> particularly large netCDF file in their collection?
>
> Thanks in advance, have a great evening all,
>
> -Ward
>
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