Gravity increase at the South Pole

John C. Behrendt

doi:10.1126/science.155.3765.1015

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Gravity increase at the South Pole

John C. Behrendt

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Abstract

Measurements made between December 1957 and January 1966 of the gravity difference between the McMurdo Sound pendulum station, which is on bedrock, and the South Pole station, which is on the Antarctic ice sheet, show a gravity increase at the South Pole of 0.11 milligals per year. The most likely hypothesis for the increase is that it was caused by ice flowing downslope across a gravity gradient and by the sinking of the South Pole station as a result of accumulation of ice. An alternate hypothesis that the gravity increase was caused by a decrease in ice thickness, of about 40 centimeters per year, is theoretically possible but is not supported by direct evidence.

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John C. Behrendt. 1967. Gravity increase at the South Pole. https://doi.org/10.1126/science.155.3765.1015

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