Monte Carlo study of UAV-measurable albedo over Arctic Sea ice

Citation:
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.

Date Published:

2018/01

Keywords:

coastline, engineering, fluxes, Meteorology & Atmospheric Sciences, model, ocean, optical-properties, radiative-transfer

Abstract:

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.

Notes:

n/a

Website

DOI:

10.1175/jtech-d-17-0066.1