Study: Less ice on New England rivers
November 8, 2005Federal scientists say there's increasing evidence the number of days of ice on northern New England rivers have declined significantly in recent decades.
U.S. Geological Survey scientists examined data from stream-flow gauging stations in Maine, New Hampshire, and Vermont.
They looked specifically at the number of days each year of ice-affected flow -- days when there's enough ice in a river to affect the relation between the height and the flow of the river.
They found such days decreased significantly during the 20th century on 12 of 16 rivers they studied. The total number of winter days of ice-affected flow decreased by 20 days from 1936 to 2000, with most of the decrease occurring since the 1960's.
Only four of the 16 rivers had significantly later first dates of ice-affected flow during the fall (ice-in), but 12 of the 16 rivers had significantly earlier spring ice melting. On average, ice-out dates became earlier by 11 days from 1936 to 2000, again with most of the change occurring since the 1960's.
The research is published in the journal Climatic Change.
Copyright 2005 by United Press International
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