Last week, the National Snow and Ice Data Center came out with the estimate that we did not quite ​set a record for the minimum extent of Arctic sea this year. Rather, 2011 seems to have come in a slight second to 2007.

However, another scientific group does claim that we've hit a new record. Who's right?

I don't know, but I don't think either bit of news is the most important thing to focus on. For as Skeptical Science points out, we also just learned that total sea ice volume reached a new low in 2010 (wonky hide-the-punchline paper here). And that is, to my mind, a much bigger deal than what total sea ice extent is doing on a year by year basis.

Remember, extent is a measure of area covered, and volume is a measure of total ice mass. (More clarification here.)

There is a strong case that volume matters more, because extent can be misleading. Why?

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.

A naturally forming ice dam caused water to leak into and overflow a toxic gold tailings pond in Yellowknife, Northwest Territories on May 14. The water is now draining back into the creek, which feeds to Back Bay on Great Slave Lake a few kilometres downstream. Great Slave Lake is the second largest lake in the Northwest Territories, the deepest in North America, and the 9th largest in the world. 

Originally one of the most pristine bodies of water in the world, the lake water was rendered undrinkable by pollution from the mining industry. The people of Yellowknife have sourced their water elsewhere, until now. City officials have tabled a proposal to source Yellowknife’s drinking water from Yellowknife Bay, which encompasses Back Bay, connected to the recent leak.

The Giant tailings hold the toxic byproducts of decades of gold mining, including tonnes of dangerous arsenic trioxide. The gold roasting process that produced seven million ounces of gold began in the 1940s at the city’s Giant gold mine, and was discontinued in 2004. The gold deposits were contained in arsenopyrite mineral formations, necessitating the separation of gold from arsenic, leaving 237,000-260,000 tonnes of highly toxic, water soluble arsenic trioxide dust, stored in 15 underground chambers a few hundred metres from Great Slave Lake.

A paper published this week in the prestigious journal Nature shows that in fact Antarctica is getting warmer, consistent with an overall trend of global temperature rise.

For years, industry-funded “skeptics” have been harping on in the mainstream media that Antarctica was getting colder instead of warmer. This apparently was evidence that global warming was all a big mistake.

Stating the obvious, the authors of this latest study said that warming temperatures in Antarctica are “difficult to explain” without linking them to carbon emissions from the burning of fossil fuels.

Misinformation about Antarctic cooling has been frustrating for researchers trying to communicate the seriousness of climate change to the public.

“The thing you hear all the time is that Antarctica is cooling and that’s not the case,” said Eric Steig of the University of Washington in Seattle, lead author of the study in Thursday’s edition of the journal Nature.

DesmogBlog was contacted this month by Nature – the most prestigious science journal in the world  – about our latest posting on the Deep Space Climate Observatory. 

It seems their editors were interested in the news we broke that the Air Force was considering launching this $100 million mothballed spacecraft – minus the Earth observing instruments.

Last week they published an 800 word article based on information we provided to them about this bizarre story.

Alas, our extensive research on the DSCOVR mission was not mentioned in the Nature article, but such is the lot of a blogger.

More importantly, the exposure provided by this piece in one of the premier journals in the world will hopefully light a fire under NASA to not to kill this vital mission.

With the Canadian federal election off to the races, DeSmogBlog has deployed an army of polar bears across Canada that will be working to raise the profile of climate change issues, especially around the environmental impacts of Alberta's oil sands operations.

The campaign is called the Arctic Front, and many of our regular readers will remember that we began this campaign during the Alberta provincial election earlier this year. Since then we have expanded our capabilities and now have polar bears stationed across the country, ready to get out the message at town hall forums,debates, rallies and other events.