Typical surface albedos of major surface types

Typical albedos for major surface types in the Arctic are summarized in Table 5.3. There is a wide range of values even within the general categories. In part, the range is explained by small-scale topography as it influences the geometry of insolation and heterogeneities in the physical properties of the surface being considered. For example, the albedo of tundra or boreal forest can differ strongly over small space scales due to variations in species distribution, leaf area, soil characteristics, and soil moisture.

Table 5.3 Representative albedos for different Arctic surfaces compiled from numerous sources

Fresh snow 0.70-0.90

Melting snow 0.50-0.60

Water 0.06-0.10a

Dry tundra 0.23-0.26

Wet tundra 0.10-0.20

Multiyear sea ice 0.55-0.75

Thick firstyear sea ice 0.30-0.60

Meltponds on sea ice 0.15-0.40

Notes: a Varies widely with solar zenith angle

Most surfaces are forward scattering and scatter differently over different portions of the solar spectrum. Hence the range also manifests variations in the spectral nature of the solar flux and the relative magnitude of direct versus diffuse components. Snow cover, both on land and sea ice, dominates the Arctic for much of the year and merits special attention. Warren (1982), Barry (1996), and Nolin and Liang (2000) provide comprehensive reviews. Maykut (1986) discusses the spectral reflectance and albedo characteristics of sea ice.

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