[ldm-users] Problem calculating GOES-16 brightness temperature from radiance

• To: ldm-users@xxxxxxxxxxxxxxxx
• Subject: [ldm-users] Problem calculating GOES-16 brightness temperature from radiance
• From: Arthur A Person <aap1@xxxxxxx>
• Date: Fri, 12 Jan 2018 08:43:56 -0500 (EST)

Hi... 

I'm trying to calculate brightness temperature from radiance for GOES-16 IR 
channel 7 using rebroadcast data 
but my values compared to McIDAS imagery are coming out 15 to 20 degrees C too 
warm. I'm using the following 
values and code: 

Test imagery: 
OR_ABI-L1b-RadC-M3C07_G16_s20180112232223_e20180112235008_c20180112235045.nc 

rad (radiance) is read in from and auto-scaled by netCDF, 
planck_fk1: 202263.0 
planck_fk2: 3698.18994140625 
planck_bc1: 0.4336099922657013 
planck_bc2: 0.9993900060653687 

bt = ( planck_fk2 / np.log( (planck_fk1/rad)+1 ) - planck_bc1 ) / planck_bc2 
bt = bt - 273.15 

Can anyone tell me if I'm missing a step or spot a dumb mistake? 

Thanks... Art 

-- 
Arthur A. Person 
Assistant Research Professor, System Administrator 
Penn State Department of Meteorology and Atmospheric Science 
email: aap1@xxxxxxx, phone: 814-863-1563 

• Follow-Ups:
  • Re: [ldm-users] Problem calculating GOES-16 brightness temperature from radiance
    • From: Pete Pokrandt