Arctic multiyear ice classification and summer ice cover using passive microwave satellite data

The ability to classify and monitor Arctic multiyear sea ice cover using multispectral passive microwave data is studied. Sea ice concentration maps during several summer minima have been analyzed to obtain estimates of ice surviving the summer. The results are compared with multiyear ice concentrations derived from data the following winter, using an algorithm that assumes a certain emissivity for multiyear ice. The multiyear ice cover inferred from the winter data is approximately 25 to 40% less than the summer ice cover minimum, suggesting that even during winter when the emissivity of sea ice is most stable, passive microwave data may account for only a fraction of the total multiyear ice cover. The difference of about 2×106 km2 is considerably more than estimates of advection through Fram Strait during the intervening period. It appears that as in the Antarctic, some multiyear ice floes in the Arctic, especially those near the summer marginal ice zone, have first-year ice or intermediate signatures in the subsequent winter. A likely mechanism for this is the intrusion of seawater into the snow-ice interface, which often occurs near the marginal ice zone or in areas where snow load is heavy. Spatial variations in melt and melt ponding effects also contribute to the complexity of the microwave emissivity of multiyear ice. Hence the multiyear ice data should be studied in conjunction with the previous summer ice data to obtain a more complete characterization of the state of the Arctic ice cover. The total extent and actual areas of the summertime Arctic pack ice were estimated to be 8.4×106 km2 and 6.2×106 km2, respectively, and exhibit small interannual variability during the years 1979 through 1985, suggesting a relatively stable ice cover.

[1]  D. Eppler,et al.  Digital Processing of Passive Ka-Band Microwave Images for Sea-Ice Classification , 1984 .

[2]  S. Ackley,et al.  Passive microwave in situ observations of Winter Weddell Sea ice , 1989 .

[3]  S. Wharton,et al.  The Land Analysis System (LAS) - A general purpose system for multispectral image processing , 1987 .

[4]  R. B. Alley.  Texture of polar firn for remote sensing , 1987 .

[5]  W. Campbell,et al.  Beaufort Sea ice zones as delineated by microwave imagery , 1976 .

[6]  A. K. Fung,et al.  Emission from an inhomogeneous layer with irregular interfaces , 1981 .

[7]  R. E. Moritz.  The Ice Budget of the Greenland Sea. , 1988 .

[8]  G. Jackson,et al.  Concurrent remote sensing of Arctic sea ice from submarine and aircraft , 1991 .

[9]  F. Carsey.  Summer Arctic sea ice character from satellite microwave data , 1985 .

[10]  H. Zwally,et al.  Time-dependence of sea-ice concentration and multiyear ice fraction in the Arctic Basin , 1978 .

[11]  Per Gloersen,et al.  Variations in the Arctic, Antarctic, and global sea ice covers during 1978-1987 as observed with the Nimbus 7 scanning multichannel microwave radiometer , 1988 .

[12]  H. Zwally,et al.  Antarctic Sea Ice, 1973-1976: Satellite Passive-Microwave Observations , 1983 .

[13]  H. Jay Zwally,et al.  ASPECTS OF ARCTIC SEA ICE OBSERVABLE BY SEQUENTIAL PASSIVE MICROWAVE OBSERVATIONS FROM THE NIMBUS-5 SATELLITE. , 1984 .

[14]  Ola M. Johannessen,et al.  Norwegian Remote Sensing Experiment: Evaluation of the Nimbus 7 scanning multichannel microwave radiometer for sea ice research , 1983 .

[15]  D. A. Rothrock,et al.  Principal component analysis of satellite passive microwave data over sea ice , 1988 .

[16]  H. Zwally,et al.  Comparison of Observed and Modeled Ice Motion in the Arctic Ocean , 1987, Annals of Glaciology.

[17]  John E. Walsh,et al.  Multiyear sea ice in the Arctic: Model‐ and satellite‐derived , 1990 .

[18]  R. Colony,et al.  Sea ice motion as a drunkard's walk , 1985 .

[19]  W. Campbell,et al.  Satellite and aircraft passive microwave observations during the Marginal Ice Zone Experiment in 1984 , 1988 .

[20]  Donald J. Cavalieri,et al.  Arctic sea ice 1973–1987: Seasonal, regional, and interannual variability , 1989 .

[21]  R. Ramseier,et al.  An algorithm to measure sea ice concentration with microwave radiometers , 1985 .

[22]  T. Grenfell,et al.  Temporal variations of the microwave signatures of sea ice during the late spring and early summer near Mould Bay NWT , 1985 .

[23]  P. Guest,et al.  Variations of mesoscale and large‐scale sea ice morphology in the 1984 Marginal Ice Zone Experiment as observed by microwave remote sensing , 1987 .

[24]  R. Barry,et al.  Arctic sea ice characteristics and associated atmosphere — Ice interactions in summer inferred from SMMR data and drifting buoys: 1979–1984 , 1989 .

[25]  W. Campbell,et al.  Determination of sea ice parameters with the NIMBUS 7 SMMR , 1984 .

[26]  W. Campbell,et al.  Aircraft measurements of microwave emission from Arctic Sea Ice , 1971 .

[27]  Walter B. Tucker,et al.  Physical properties of summer sea ice in the Fram Strait, June-July, 1984 , 1987 .

[28]  E. Ronald,et al.  Fram Strait ice flux calculations and associated Arctic ice conditions , 1989 .

[29]  T. Vinje.  The Drift Pattern of Sea Ice in the Arctic with Particular Reference to the Atlantic Approach , 1982 .

[30]  F. D. Carsey,et al.  Arctic sea ice distribution at end of summer 1973–1976 from satellite microwave data , 1982 .

[31]  Josefino C. Comiso,et al.  Characteristics of Arctic winter sea ice from satellite multispectral microwave observations , 1986 .

[32]  B. E. Troy,et al.  Microwave emission from high Arctic sea ice during freeze-up , 1984 .

[33]  Thomas J. Schmugge,et al.  SI1GNATJURE$ O F FIRST-YEAR AND :,:MULTIYEAR , 2009 .

[34]  Vassilios Makios,et al.  Dielectric properties of fresh and sea ice at 10 and 35 GHz , 1974 .

[35]  J. C. Comiso,et al.  Sea ice effective microwave emissivities from satellite passive microwave and infrared observations , 1983 .