The Annual Arctic Sea Ice Drama Begins

Wed, 2011-07-27 09:33Chris Mooney
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The Annual Arctic Sea Ice Drama Begins

In my last post, I discussed how the increasing risk of devastating heat waves—unlike the worsening of tornadoes—is definitely a phenomenon we can link to global warming. And now, as summer plods on, it’s time to begin paying attention to another one: the continuing decline of Arctic sea ice.

The extent of ice covering the Arctic has been declining for decades, and reached a record low in September of 2007, nearly 40 percent below its long term average. This wasn’t solely the product of global warming—weather patterns also have a lot to do with ice extent, and they contributed to the 2007 record. 

Nevertheless, much like the worsening of heat waves, Arctic ice decline is one of the most obvious  impacts of global warming—and this year, it’s possible that Arctic ice extent might reach a minimum even lower than it did in 2007.

The annual Arctic sea ice minimum occurs sometime in September—that’s when the ice cover has received the most summer heat and shrunken accordingly, before beginning to build again as winter sets in. There’s a natural cycle of melt and freeze, but global warming is perturbing that cycle.

As I reported in New Scientist last year, the ice doesn’t simply rebound, during winter, back to where it was before. Rather, total ice volume has been declining, and most ice is now “first year” ice, rather than “multi-year” ice. In other words, it melts entirely in the summer, rather than surviving a full cycle and adding to its girth over years.

Which brings us to 2011: The National Snow and Ice Data Center, at the University of Colorado, is reporting that as of now, ice extent is even lower than where it was at this time of year in 2007, the record-breaker. The melt got an early start this year in many parts of the region, and has been going gangbusters ever since.

That doesn’t ensure there will be a record shattering: Weather patterns, the alignment of winds, and many other factors ultimately determine what happens with the ice and whether a record will be broken. But overall, you can bet Arctic ice extent will keep trending downward, breaking records regularly. The ice will also be losing volume steadily, and becoming “younger”: less and less of it will even be a year old.

Oh…and you can bet that deniers will have some way of explaining all of this. This year, they may have to start the rationalizations in just over a month.

Previous Comments

Oh, by the way, his work is not ‘on hold’ as you say, is on administrative leave and facing accusations of scientific misconduct by the federal agency that employs him.
Stop playing the ‘victim’ card in these cases!

‘Oh, by the way, his work is not ‘on hold’ as you say, is on administrative leave and facing accusations of scientific misconduct by the federal agency that employs him.
Stop playing the ‘victim’ card in these cases!’

So, Einstein, what effect do you think this has:

‘They have rifled through all of Dr. Monnett’s e-mails and seized his papers and equipment, impeding his ability to work even before he was ordered to stay home;’

on Dr Monnett’s ability to continue his work.

DK to the fore with you here that is for sure!

‘And now for the true story, from the Anchorage daily news;’

Which is just an echo of your first.

http://thinkprogress.org/romm/2011/07/30/283748/polar-bears-still-screwed-by-global-warming/ - Regards, Tom Gray, Wind Energy Communications Consultant

This blog has attracted an infestation of braying deniers– sad to see, when we know plenty about how much change in net insolation occurs during glacial cycles, and how that compares to the impact of the CO2 we’re adding to the atmosphere. We know it’s anthropogenic, we know the CO2 levels are increasing much faster than they did leading up to the last rapid warming, and we know what it does to retain heat in the climate system. These big bold denunciations of the idea that we could have any effect on the climate system reveal nothing but the ignorance and arrogance of the braying ignorati. It would be nice to have a serious discussion of evidence, history and climate science– but that’s a tall order around here. Sad.

Too bad that not a lot of people care about our world’s oceans considering that 50% of the air we breathe comes from it. Check this video out. http://youtu.be/57_KdKrJKeM

http://psc.apl.washington.edu/wordpress/wp-content/uploads/schweiger/ice...BPIOMASIceVolumeAnomalyCurrentV2.png?%3C?php%20echo%20time%28%29%20?

The 2010 melt season was a tipping point of sharply decreasing Minimum Volumes for the Arctic. This year peak volume was of shorter duration than the maximums in 2011 and 2012. Volume started dropping soon after reacing the maximum.

If you just want to look at the surface have a look at

http://nsidc.org/data/seaice_index/images/daily_images/N_daily_concentra...

or at

http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseri...

Note that the total area has been below or close to the record low 2012 area values since 2013/May.

And still the denial goes on

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