albedo classification

A classification of sea ice using its albedo

The following table contains a classification of sea ice types using the albedo as a classifier. The numbers behind the quoted albedo values indicate the proper reference, where the value was obtained.
Total albedo is dependent on the incoming radiation because the albedo is not constant over the range of incoming short wave radiation. In general spectral albedo is highest in the short wave end of the spectrum. A higher amount of the long wave spectrum is absorbed in the atmosphere (clouds) during overcast conditions. Albedos are therefore higher by up to 0.10 in an overcast situation as compared to clear sky conditions (Perovich, 1996).

dirty ice

bare ice
0.05-0.72 melting ice
0.25-0.56 2) 0.60 3)

clean ice
0.05-0.72 new ice
0.05-0.15 5)

nilas
0.05-0.24
    dark          light
0.05-0.17 1) 0.241)

ice
0.05-0.90 young ice
0.20-0.35
grey        grey-white
0.20 1)        0.35 1)

growing bare ice
0.05-0.72

first year ice
0.24-0.64 5)

second year ice
0.70 5)

dry snow
0.80-0.90 6) multiyear ice
0.72 2)

snow covered ice
0.70-0.90

wet snow
0.70-0.80 6)

quiet open water
0.05 1)

Dirty ice
Sediment concentrations of 1000 g/m3 can reduce the albedo from 0.70 to less than 0.35 4). This is particularly important in Arctic Sea Ice. Biological material can have a similar effect.

SOURCES

1) Allison, I. R. E. Brandt, and S. G. Warren (1993) East Antarctic sea ice: albedo, thickness distribution and snow cover. J. Geophys. Res., 98, 12417-12429.

2) Grenfell, T. C. and G. A. Maykut (1977) The optical properties of ice and snow in the Arctic Basin. J. Glac., 18, 445-463.

3) Grenfell, T. C. and D. K. Perovich (1984) Spectral albedos of sea ice and incident solar irradiance in the southern Beaufort Sea. J. Geoph. Res., 89, 3573-3580.

4) Light, B., H. Eicken, G. A. Maykut, and T. C. Grenfell (1998) The effect of included particulates on the optical properties of sea ice. J. Geoph. Res., 103, 27739-27752

5) Perovich, D. K. (1996) The optical properties of sea ice. CRREL Monogr., 96-1, 25 pp.

6) Wiscombe, W. J. and S. G. Warren (1980) A Model for the spectral albedo of snow. I: Pure snow. J. Atm. Sc.,
37(12), 2712-2733.

to Sea-Ice Nomenclature Overview page

		dirty ice
	bare ice 0.05-0.72		melting ice 0.25-0.56 2) 0.60 3)


		clean ice 0.05-0.72		new ice 0.05-0.15 5)
				nilas 0.05-0.24	dark light 0.05-0.17 1) 0.241)
ice 0.05-0.90				young ice 0.20-0.35	grey grey-white 0.20 1) 0.35 1)
			growing bare ice 0.05-0.72
				first year ice 0.24-0.64 5)
				second year ice 0.70 5)
		dry snow 0.80-0.90 6)		multiyear ice 0.72 2)
	snow covered ice 0.70-0.90
		wet snow 0.70-0.80 6)
quiet open water 0.05 1)