NSIDC - Arctic Sea Ice 1 Million+ KM2 Below 2005 Record - 1st-Time Ice-Free Area Size Of California

[hatrack]

10 September 2007
Overview of current sea ice conditions
Sea ice extent continues to decline, and is now at 4.24 million square kilometers (1.63 million square miles), falling yet further below the previous record absolute minimum of 5.32 million square kilometers (2.05 million square miles) that occurred on September 20–21, 2005.

Current Sea Ice Conditions: September 9, 2007

Figure 1 provides the updated map of sea ice extent for September 9, 2007. Sea ice extent now stands at 4.24 million square kilometers (1.63 million square miles). The magenta line shows the median September monthly extent based on data from 1979 to 2000.

The Northwest Passage is still open. The Northeast Passage, along the coast of Siberia, is still closed by a narrow band of sea ice.

Figure 1: Sea ice extent for for September 9, 2007



Current sea ice conditions in context

Figure 2 is the updated time series of daily ice extent for 2007, which can be compared to the time series for 2005 and to the 1979-2000 average. Compared to conditions cited in our last entry on September 3, we have lost an additional 180,000 square kilometers (69,000 square miles) of ice, an area roughly the size of Florida. However, the rate of loss from day to day has greatly slowed.

The absolute minimum for 2007 could occur any day now. While on average, based on data from 1979 to 2000, this minimum has occurred around September 13, it has occurred as late as September 25.

Figure 2: Summer melt season Arctic sea ice extent



Yesterday's sea ice extent compared to perennial sea ice

Figure 3 further illustrates the significance of this year’s decline in sea ice. In this figure, we overlay two areas. Gray areas within the Arctic Ocean indicate where sea ice was present every day of every year from 1979 through spring 2007. Yesterday’s sea ice is in white, and the overlap areas are in light gray. The dark gray color represents the region that is ice-free for the first time in the satellite record.

What does this figure really tell us? It tells us that a large area is, for the first time since the satellite record began, not covered by sea ice.

The amount and location of summer sea ice varies from year to year, so even after twenty-eight years it would not be surprising to have some small areas that are newly ice-free each year. However, this year the first-time ice-free area is extremely large—roughly the size of the state of California.

Figure 3: September 9, 2007 sea ice extent compared
to perennial sea ice 1979 to 2006



EDIT

http://nsidc.org/news/press/2007_seaiceminimum/20070810_index.html

[phantom power]

1. I see they've had to move the scale on the graph to accomodate that pesky blue line.

[hatrack]

2. Those pesky facts! You've tried scrubbing, you've tried spinning, but they just keep coming back!

Can't wait for Michael Crichton to "explain" this away.

Oh, and I heard on NPR this morning that Rupert Murdoch is instructing Fox television executives to work energy conservation and climate into their story lines. Thankfully, the legendary independence of the Fox News Division will remain unaffected!!

[AlecBGreen]

3. yeesh

we're 20 percent lower than the previous record and there's plenty more melting ahead. I think we've found our tipping point....

[greenman3610]

4. recommended reading

"With Speed and Violence-Why Scientists Fear Tipping Points in Climate Change" by Fred Pearce


"Under a Green Sky" by Peter Ward
(you'll need to be strong to read this one..)