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Podgorny, I, Lubin D, Perovich DK.  2018.  Monte Carlo study of UAV-measurable albedo over Arctic Sea ice. Journal of Atmospheric and Oceanic Technology. 35:57-66.   10.1175/jtech-d-17-0066.1   AbstractWebsite

In anticipation that unmanned aerial vehicles (UAVs) will have a useful role in atmospheric energy budget studies over sea ice, a Monte Carlo model is used to investigate three-dimensional radiative transfer over a highly inhomogeneous surface albedo involving open water, sea ice, and melt ponds. The model simulates the spatial variability in 550-nm downwelling irradiance and albedo that a UAV would measure above this surface and underneath an optically thick, horizontally homogeneous cloud. At flight altitudes higher than 100 m above the surface, an airborne radiometer will sample irradiances that are greatly smoothed horizontally as a result of photon multiple reflection. If one is interested in sampling the local energy budget contrasts between specific surface types, then the UAV must fly at a low altitude, typically within 20 m of the surface. Spatial upwelling irradiance variability in larger open water features, on the order of 1000 m wide, will remain apparent as high as 500 m above the surface. To fully investigate the impact of surface feature variability on the energy budget of the lower troposphere ice-ocean system, a UAV needs to fly at a variety of altitudes to determine how individual features contribute to the area-average albedo.

Podgorny, I, Lubin D.  1998.  Biologically active insolation over Antarctic waters: Effect of a highly reflecting coastline. Journal of Geophysical Research-Oceans. 103:2919-2928.   10.1029/97jc02763   AbstractWebsite

Near an Antarctic coastline or sea ice edge, multiple reflection of photons between the high-albedo surface and a cloud will increase the downwelling surface insolation not only over the high-albedo surface itself but also out over the adjacent open water. This insolation enhancement is examined with a Monte Carlo radiative transfer model. The insolation enhancement extends to a typical distance of 4 km out to sea, with the most important effects being within 2 km of the coastline. The strength of the multiple reflection effect depends primarily on cloud base height and cloud optical depth and only slightly on cloud geometrical thickness. The insolation enhancement is also a function of wavelength, being larger for ultraviolet wavelengths than for the visible. This is due to a slightly greater contribution from Rayleigh scattering at the shorter wavelengths, although at ultraviolet wavelengths where ozone absorption is strong, tropospheric ozone absorption can offset the Rayleigh scattering contribution at larger cloud optical depths. On the basis of the limited range of the multiple reflection effect (2-4 km out to sea) the insolation enhancement due to the high-albedo coastline is unlikely to be a major influence on the primary productivity of all Antarctic waters; however, it may influence phytoplankton blooms near the coast and photobiological experiments carried out at coastal research stations. Also, the insolation enhancement may have significance in sea ice leads and polynyas.