My file:

variables:
	double LONGITUDE(LONGITUDE) ;
		LONGITUDE:standard_name = "longitude" ;
		LONGITUDE:long_name = "longitude" ;
		LONGITUDE:units = "degrees_east" ;
		LONGITUDE:axis = "X" ;
	double LATITUDE(LATITUDE) ;
		LATITUDE:standard_name = "latitude" ;
		LATITUDE:long_name = "latitude" ;
		LATITUDE:units = "degrees_north" ;
		LATITUDE:axis = "Y" ;
	double time(time) ;
		time:standard_name = "time" ;
		time:units = "months since 2010-01-16 00:00:00" ;
		time:calendar = "standard" ;
	double BC(time, LATITUDE, LONGITUDE) ;
		BC:long_name = "Black_Carbon" ;
		BC:_FillValue = -1.e+34


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need in this way:


variables:
	float lon(lon) ;
		lon:long_name = "Longitude" ;
		lon:units = "degrees_east" ;
		lon:standard_name = "longitude" ;
		lon:axis = "X" ;
	float lat(lat) ;
		lat:long_name = "Latitude" ;
		lat:units = "degrees_north " ;
		lat:standard_name = "latitude" ;
		lat:axis = "Y" ;
	double time(time) ;
		time:units = "days since 1850-01-01 00:00:00" ;
		time:calendar = "standard" ;
	float BC(time, lat, lon) ;
		BC:long_name = "Black_Carbon" ;
		BC:standard_name = "tendency_of_atmosphere" ;
		BC:units = "kg m-2 s-1" ;
		BC:code = 6 ;
		BC:species = "BC" ;
		BC:molecular_weight = 12.f ;
		BC:molecular_weight_units = "g mole-1" ;