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Up Topic Products and Algorithms / Satellite Data Products & Algorithms / Level 2 chlor_a conversion (locked)
- By mhess Date 2011-01-27 16:55
Are the DN values in the *.L2_LAC_OC .hdf files for the chlor_a parameter the actual values in mg/m3 or is there a conversion equation?  If conversion is necessary, can you please point me to this eqaution?  Thanks.  Mark
- By bryan Date 2011-01-27 17:07
We store chlorophyll as a float in Level-2, in mg/m^3.  No conversion is needed.  -32767.0 is the fill value.  This information is contained in the meta-data.       

float chlor_a(Number of Scan Lines, Pixels per Scan Line) ;
                chlor_a:long_name = "Chlorophyll Concentration, OC4 Algorithm" ;
                chlor_a:slope = 1.f ;
                chlor_a:intercept = 0.f ;
                chlor_a:units = "mg m^-3" ;
                chlor_a:bad_value_scaled = -32767.f ;
                chlor_a:bad_value_unscaled = -32767.f ;

-- bryan
- By mhess Date 2011-01-27 17:12
Great - that's what I had thought.  Good to get verification.  Thanks for the fast respnse. Mark
Up Topic Products and Algorithms / Satellite Data Products & Algorithms / Level 2 chlor_a conversion (locked)



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