Report: Arctic Ice Conditions: The Same As 200 Years Ago
'The extent of summer sea ice during the 19th century, insofar as it is shown in patterns of navigability inferred from ship tracks, the direct observations of explorers, and a number of native accounts, is remarkably similar to present ice climatology. A chart of northern Canada (Figure 2) shows the routes followed by discovery expeditions and their wintering locations between 1818 and 1859, and also displays the frequency that sea ice has occurred during the recent 30-year reference period 1971–2000. It is perhaps surprising that most of the Northwest Passage was navigated during the 19th century, with expedition ships coming within 150 km of completing the passage on a number of occasions'