THREDDS OPeNDAP speed Matlab

Question

Using the following code in Matlab:

nc_file_list = {'http://data.nodc.noaa.gov/thredds/dodsC/ghrsst/L2P/MODIS_A/JPL/2015/287/20151014-MODIS_A-JPL-L2P-A2015287235500.L2_LAC_GHRSST_D-v01.nc.bz2'};


temp.sl = ncreadatt(nc_file_list,'/','northernmost_latitude');

I try to get a single attribute from a netcdf file on a THREDDS OPeNDAP server. Ive been told this should be very quick as the netcdf philosophy is build around accessing small parts of data in big data sets.

The total size of the netcdf file is around 20 Mb. Running this code takes 17 seconds (internet speed is 5 Mb/s).

I need to process 19,000 files so I want this netcdf attribute reading to go alot quicker. Is there a way to read the attribute of the link given above in under 1 second?

Answer 1

You can use the THREDDS DAS Service as is explained by this answer:

Answer 2

The file is bz2-compressed, so the whole thing must be decompressed before the NetCDF library can perform random access operations on it. There's no way to avoid that.