SGP/IRT/E9 - Sky temperature bias

Measurements of sky temperature, especially those <250K, were positively biased compared 
with AERI because there was no compensation for the reflectivity of the gold mirror. The 
problem was corrected by changing the IRT emissivity from 1.000 to 0.987.

Use sky temperature measurements less than 230K with caution. Biases as large as 30K have 
been observed when the actual temperature, as measured by AERI, is less than 210 K.

• sky_ir_temp

• sky_ir_temp_min
• sky_ir_temp_max
• sky_ir_temp