The determination of land emergence from sea level observations in southeast Alaska

Abstract

Sea level observations in southeast Alaska show a maximum rate of land emergence relative to the level of the sea of 3.96 cm/yr at Bartlett Cove, Glacier Bay. A conservative estimate of total maximum emergence, based on direct observations, is 154 cm from 1922 to 1960. Land emergence at a rate greater than 1.9 cm/yr is found within an area roughly bounded by Skagway, Juneau, the outer coast, and a north-south line located about half-way between the head of Glacier Bay and Yakutat. The area of emergence is reniform, with its major axis oriented in a north-south direction. Its steepest slopes lie to the south and west. The feature appears to be the result of rebound from present localized deglaciation or the combination of present localized and general post-Wisconsin deglaciation. The study is based on 28 separated series of sea level observations extending as far back as 1887 and 5 continuous series, the oldest extending back to 1919. The oldest series of observations within the 1.9 cm/yr emergent zone dates from 1902.