Old satellite data, ships' logbooks could reveal history of Arctic ice

Interpreting the Nimbus data is a tricky process involving painstaking analysis of reams "archaic, two-inch tape," according the NSIDC. But if the researchers can construct a high-resolution, season-by-season record of ice expansion and contraction for the 15 years before 1979, the extended timeline will provide a much clearer picture of the trends that led to this decade's alarming Arctic ice retreat.