Estimating Cloud Optical Depth from Surface Radiometric Observations: Sensitivity to Instrument Noise and Aerosol Contamination

Abstract The spectral-difference algorithm of Barker and Marshak for inferring optical depth τ of broken clouds has been shown numerically to be potentially useful. Their method estimates cloud-base reflectance and τ using spectral radiometric measurements made at the surface at two judiciously chosen wavelengths. Here it is subject to sensitivity tests that address the impacts of two ubiquitous sources of potential error: …