Annual variability of white and black sky spectral albedo at the Central Facility

 
Poster PDF

Authors

Joseph J. Michalsky — NOAA/Earth System Research Laboratory/Global Monitoring Division & CU-Boulder/Cooperative Institute for Research in Environmental Sciences
Ellsworth G. Dutton — NOAA/OAR/ESRL
Gary B. Hodges — NOAA- Earth System Research Laboratory

Category

Radiation

Description

We explore the annual variability of both white- and black-sky albedo at the Southern Great Plains Central Facility using lamp-calibrated data from the E13 and C1 MFRSRs, and the 10m and 25m MFRs. These instruments measure at six narrowband channels: 415, 500, 615, 673, 870, and 940 nm. White- sky albedo is the reflectance of the surface under diffuse-sky conditions. Black-sky albedo, also known as directional-hemispherical reflectance, is the reflectance of the surface from direct-beam illumination only. Using the surface albedo measured under overcast conditions, the components of the upwelling signal can be separated under black-sky conditions. The primary assumption for this analysis is that the diffuse albedos are comparable under both cloudy and clear-sky conditions.