Ice coverage

Review from the Office of the Ombudsman | English Services


Statement on The National that in 2008 “ice coverage shrank to the second- lowest level since experts started tracking it”

You wrote last year to complain about a brief story on The National on September 17, 2008, that said that in 2008 “ice coverage shrank to the second-lowest level since experts started tracking it.”

You said that The National had “misreported” the data and “twisted” the story; that, in fact, there was “more ice than the previous year.”

The then Acting Executive Producer of The National, Mark Harrison, responded saying that the source of the story, The National Snow and Ice Data Center, had described the satellite survey information in the same way as the CBC story. He pointed to information that appeared to show that the “strong negative trend in summertime ice extent characterizing the past decade continues.”

You were not satisfied with the response and asked for a review.

While you are correct that the 2008 data showed an increase in Artic ice, the major sources of scientific data characterize the increase in the same way that The National did. I cite an extract of a study by the same National Snow and Ice Data Center:

“The Arctic sea ice September minimum extent reached new record lows in 2002 (15.3 percent below the 1979-2000 average), 2005 (20.9 percent below), and 2007 (39.2 percent below). In 2007, Arctic sea ice broke all previous records by early August—a month before the end of melt season (see Arctic Sea Ice Shatters All Previous Record Lows). In 2008, the September minimum was the second lowest on record, only 9 percent above 2007, despite cooler summer conditions (see Arctic Sea Ice Down to Second- Lowest Extent; Likely Record-Low Volume).

Decline Causes
Greenhouse gases emitted through human activities and the resulting increase in global mean temperatures are the most likely underlying cause of the sea ice decline, but the direct cause is a complicated combination of factors resulting from the warming, and from climate variability. The Arctic Oscillation (AO) is a see-saw pattern of alternating atmospheric pressure at polar and mid-latitudes. The positive phase produces a strong polar vortex, with the mid-latitude jet stream shifted northward. The negative phase produces the opposite conditions. From the 1950s to the 1980s, the AO flipped between positive and negative phases, but it entered a strong positive pattern between 1989 and 1995. So the acceleration in the sea ice decline since the mid 1990s may have been partly triggered by the strongly positive AO mode during the preceding years (Rigor et al. 2002 and Rigor and Wallace 2004) that flushed older, thicker ice out of the Arctic, but other factors also played a role.”

In my research I discovered more recent data from scientists in Canada and Greenland that substantiate the notion that the small increase last year was not a “positive” development.

It would appear that The National had a solid basis for its brief story and was correct to put the slight increase in 2008 in context.


There was no violation of CBC's Journalistic Standards and Practices.

Vince Carlin
CBC Ombudsman