Field Notes: The Polar Field Services Newsletter

Arctic Sea Ice Clearing Early from Northwest Passage

Daily Arctic sea ice extent on August 16 was 5.95 million square kilometers (2.30 million square miles). The orange line shows the 1979 to 2000 median extent for that day. The black cross indicates the geographic North Pole.

The National Snow and Ice Data Center’s update on Arctic sea ice on Aug. 17 underscores the dramatic difference between present day ice melt and that from 100 years ago. According to the most recent data sea ice presence in the Northwest Passage is “well below the 1969 to 2000 average.” Although the passage isn’t entirely clear, there is little coverage. Here’s what NSIDC had to say about the conditions:

Conditions in the Northwest Passage are quite variable and do not necessarily reflect overall conditions in the Arctic. However, today’s conditions in the Northwest Passage would likely astonish 19th century explorers such as McClure, Franklin, and Amundsen. In upcoming decades, the passage will be increasingly likely to open during summer.

Throughout the Arctic there has been rapid and significant ice melt and the remaining ice (known as sea ice extent) is the second lowest on record.

Sea ice data updated daily, with one-day lag. Orange line in extent image (left) and gray line in time series (right) indicate 1979 to 2000 average extent for the day shown.

According to the data, July arctic sea ice covered an average of 3.2 million square miles (8.4 million square kilometers). This is 16.9 percent below the 1979-2000 average extent and the second lowest July extent since records began in 1979. The record low July was set in 2007. This was the 14th consecutive July with below-average Arctic sea ice extent. July 1996 was the last year that had above-average sea ice extent. —Rachel Walker

Leave a Reply

Your email address will not be published. Required fields are marked *