Longitude/Latitude from NetCDF with (row,column)

Question

I downloaded a "Sentinel-3 Land Surface Temperature" netcdf file. I want to get the longitude and latitude for each temperature entry in the file. Well the file has pairs of rows and column. Using Python I can get the temperature using :

from netCDF4 import Dataset
with dataset as ncFile:
 nc_attrValue = ncFile.variables['LST'][1000][1000]
 print(type(nc_attrValue))

So any idea how I can convert [1000][1000] to longitude or latitude. Here is a snapshot of the file netcdf file converted to .cdl using NCO:

 netcdf LST_in {
dimensions:
 columns = 1500 ;
 orphan_pixels = 187 ;
 rows = 1200 ;
variables:
short LST(rows, columns) ;
 LST:_FillValue = -32768s ;
 LST:add_offset = 290.f ;
 LST:long_name = "Gridded Land Surface Temperature" ;
 LST:scale_factor = 0.002f ;
 LST:standard_name = "surface_temperature" ;
 LST:units = "K" ;
 LST:valid_max = 32767s ;
 LST:valid_min = -32767s ;
// global attributes:
 :absolute_orbit_number = 12616U ;
 :comment = " " ;
 :contact = "[email protected]" ;
 :creation_time = "20180720T144045Z" ;
 :history = " 2018年07月20日T14:40:45Z: PUGCoreProcessor /data/ipf-s3/workdir47/568114279/JobOrder.568114279.xml" ;
 :institution = "SVL" ;
 :netCDF_version = "4.2 of Mar 13 2018 10:14:33 $" ;
 :product_name = "S3A_SL_2_LST____20180720T124923_20180720T125223_20180720T144045_0179_033_323_3240_SVL_O_NR_003.SEN3" ;
 :references = "S3IPF PDS 005 - i2r7 - Product Data Format Specification - SLSTR, S3IPF PDS 002 - i1r6 - Product Data Format Specification - Product Structures, S3IPF DPM 007 - i1r8 - Detailed Processing Model - SLSTR Level 2" ;
 :resolution = "[ 1000 1000 ]" ;
 :source = "IPF-SL-2 06.13" ;
 :start_offset = 21649 ;
 :start_time = "2018-07-20T12:49:23.587859Z" ;
 :stop_time = "2018-07-20T12:52:23.279310Z" ;
 :title = "SLSTR Level 2 Product, Land Surface Temperature measurement" ;
 :track_offset = 998 ;
data:
 LST =
 _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, 
 _, _, _, _, _, _, _, -7188, -6706, -6884, -6249, -6173, -6721, -6924,

Answer 1

# Imports
from netCDF4 import Dataset
# Define reading function
def slstr_read_nc(fdir):
 """
 Read lon, lat SLSTR data
 
 Args:
 fdir = string with the path and filename of the SLSTR product
 Returns:
 lon -- 2d ndarray of longitude
 lat -- 2d ndarray of latitude
 """
 # Read Data
 # Open NetCDF
 nc = Dataset(fdir, mode='r')
 
 # Read variables from ncdf
 lon = nc.variables['longitude_in'][:]
 lat = nc.variables['latitude_in'][:]
 # Close netcdf
 nc.close()
 
 return lon, lat
# Define path and NC filename
path = './'
fname = 'geodetic_in.nc' # this is the lat, lon NC file
fdir = os.path.join(path, fname)
# extract lat, lon
lon, lat = slstr_read_nc(fdir)
lon.shape
lat.shape

Output:

>>> lon.shape
(1200, 1500)
>>> lat.shape
(1200, 1500)