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Electrolytic conductivity of snow and glacier ice from Antarctica and Greenland

1968; American Geophysical Union; Volume: 73; Issue: 12 Linguagem: Inglês

10.1029/jb073i012p03643

2156-2202

Anthony J. Gow,

Winter Sports Injuries and Performance

Conductivity measurements have been made on snow and ice samples from pits and deep drill holes at a number of localities in Antarctica and Greenland. Conductivities of the order of 1–2 μmhos/cm only were recorded at the inland sites. Data from deep cores representing more than 1900 yr of continuous snow accumulation at Byrd station, Antarctica, and more than 400 yr of deposition at Inge Lehmann, Greenland, showed no significant variations of conductivity with time. Measurements of freshly precipitated snow from a single coastal location in McMurdo Sound, Antarctica, also yielded relatively low conductivities of the order of 3–4 μmhos/cm. The substantial increase observed in the conductivity of core samples from near the surface of the Ross Ice Shelf at Little America V can most probably be attributed to wind-borne salts of marine origin that had accumulated on the surface after the snow was deposited. A peak conductivity of 49 μmhos/ cm was recorded in snow estimated to have been deposited within 20 km of the seaward edge of the Ross Ice, Shelf, and the maritime effect could still be detected in samples deposited more than 40 km from the ice front. For samples deposited at distances of greater than 200 km from the edge of the Ross Ice Shelf conductivities never exceeded 2 μmhos/cm. The very low conductivities observed in ice cores from near the bottom of the Ross Ice Shelf confirm earlier conclusions, based on detailed petrographic studies of the cores, that the 258-meter-thick ice shelf at Little America V is composed entirely of glacial ice.