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I believe it depends on how it's done. If they use scrubbers to take the SO2 out, there won't be a similar reduction in CO2.
Go, Schiedam! :-)
Everybody wants clean air. We in the West do, the Chinese do, and it'll also be high on the wish list of Indians and people from other developing nations, once their living standards go up. But good things can also have drawbacks. And in this case it could be a... Continue reading
Posted 4 days ago at Arctic Sea Ice
AiG, my hunch is that it's because of low pressure areas dominating the Arctic (expressed by a highly positive Arctic Oscillation that had the same effect in November 2013) keeping the cold in the centre of the Arctic and winds pushing the ice inwards at the edges (for instance on the Atlantic side of the Arctic where there's a lot of room for expansion). This doesn't mean all that much in itself. A lack of expansion might well mean the core is getting thicker. And the effects of a positive AO may be different from January onwards, etc. But that is what I think is causing the hiatus, I mean the slowdown in growth. But growth will resume at a pace similar to the average, either soon or a few weeks from now.
The original was 3.2 MB, which makes the page load slow for some people, so I tried to make it smaller, but didn't get it lower than 2.7 MB. Btw how do you ask for email notifications of replies to comments here? Unfortunately, I don't believe there is such a function, like there is in Wordpress and Blogger, which is really handy.
Compared to what? What dataset?
Albeit we can't assume the melting season already would have started, can we? No, let's not assume that. :-P But, as alluded to in the previous blog post, the (very) positive AO has resulted in an ice growth hiatus, just like it did in 2013 (though less pronounced).
Here's a Discover magazine article I noticed a couple of days ago, containing a nice (but big) animation that shows how many days per year (parts of) the Arctic will be ice-free in the future if things keep going as they are: If global warming continues unabated, humans are likely... Continue reading
Posted Nov 14, 2015 at Arctic Sea Ice
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center: Yes, I'm still focused on how 2015 is doing compared to the 2013 and 2014 rebound years, and... Continue reading
Posted Nov 4, 2015 at Arctic Sea Ice
the rate of refreeze this year has been pretty amazing, if you are following the IJIS numbers. You can say that again. 1 million km2 in just 6 days! That's pretty impressive.
Toggle Commented Oct 18, 2015 on PIOMAS October 2015 at Arctic Sea Ice
Definitely an interesting graph, Pete. Thanks for posting. In a sense this is acting as a negative feedback on ice loss. Indeed, this ties in with the Slow Transition stuff that Chris Reynolds has been writing about for some time now.
Toggle Commented Oct 16, 2015 on PIOMAS October 2015 at Arctic Sea Ice
I'm a bit late with this, as the latest data (up to September 30th) was released last week. To make up, here's Andy Lee Robinson's latest video showing the PIOMAS sea ice volume minimum long-term trend: --- Here is the updated Arctic sea ice volume graph as calculated by the... Continue reading
Posted Oct 15, 2015 at Arctic Sea Ice
You crazy alarmist, you. ;-)
Toggle Commented Oct 13, 2015 on 2015 minimum overview, part 2 at Arctic Sea Ice
As you know, I did use snow cover in June for my submission to SIPN July report, where I predicted 4.61 M km^2 for the Sept minimum. The final NSIDC number for the Sept minimum is 4.63, which makes my entry the closest of all SIPN entries, and makes it look like I know what I'm talking about :o) I had noticed that, Rob. Well done!
Toggle Commented Oct 4, 2015 on 2015 minimum overview, part 2 at Arctic Sea Ice
I think it's reasonable, although mainstream opinion (I believe, haven't done a survey) is between 2030 and 2040. I personally believe it could happen at any particular melting season under exceptional circumstances, like weak initial ice state because of a cloudy winter, heavy preconditioning during May and June, followed by a July we saw this year (or warmer), and then a warm, stormy August. At the same time some negative feedback might kick in, or some unforeseen natural variability keeping things on a plateau*. Of course, that would be a reprieve, nothing more. Whether the Arctic practically melts out before 2030 or after 2050 is not all that relevant (especially if human societies keep opting for business-as-usual). It's about the process, not the end result, as the consequences are most probably already upon us and becoming more and more visible. * I don't want to think about it, but it could just as easily be the opposite: positive feedback kicking in, unforeseen natural variability kicking off the turbo.
Toggle Commented Oct 2, 2015 on 2015 minimum overview, part 2 at Arctic Sea Ice
Neven, So they essentially quantified a reason for a feedback that they already knew existed and was affecting the long-term trend? Bob, my understanding - based on this BBC article - is that they didn't really quantify all that much, but rather found evidence for the heat eddying upwards. Like the mission's chief scientist, Jennifer MacKinnon, says: "The strength of [these currents] has been incredible," Dr MacKinnon said. "We now need to disentangle what the contribution of that process is to the multi-year, inexorable decline of the sea ice." And the NSIDC's Dr Julienne Stroeve comments: "I think it is quite important to understand this type of mixing of warmer ocean waters at depth with the sea ice," she told the BBC. It will be crucial, Dr Stroeve added, to quantify exactly how much heat is reaching the ice and how much melting it has caused. "In 2007 more than 3m of bottom melt was recorded by [an] ice mass balance buoy in the region, which was primarily attributed to earlier development of open water that allowed for warming of the ocean mixed layer. But perhaps some of this is also a result of ocean mixing."
Toggle Commented Oct 2, 2015 on 2015 minimum overview, part 2 at Arctic Sea Ice
I think Barry meant September average or monthly minimum instead of 'anomaly'.
Toggle Commented Oct 2, 2015 on 2015 minimum overview, part 2 at Arctic Sea Ice
It's clear - and always has been - that heat in the ocean plays and has played a big part in the long-term thinning of the ice pack (read my blog post on Ocean Heat Flux for instance). They haven't documented the effect per se, but rather one of the possible reasons of the effect, the others being ocean currents bringing heat into the Arctic (again, see that blog post), and heat coming in through the ice-albedo feedback. Unfortunately it's very difficult to quantify, but scientists are working on that. It's important stuff, not just because of the implications for AGW etc.
Toggle Commented Oct 2, 2015 on 2015 minimum overview, part 2 at Arctic Sea Ice
AiG, there's a graph for 'decline in spring snow cover' on MA Rodger's website that runs until Feb 2015. Here's a bar graph for Spring with trend line from Rutgers University Global Snow Lab. And here's Fall and Winter. As you can see the latter two have upward trends, which probably has to do with all that open water at the end of the melting season dumping moisture in the atmosphere. Still, this negative feedback is quickly overcome in Spring and Summer. I'm still surprised at that. But maybe Spring/Summer snow cover has now reached a limit, I don't know. It'd be interesting to see if the snow line has retreated further North.
bobcobb, I haven't yet looked into it as much as I should have, but yeah, this could be a serious positive feedback. There's enough heat in the lower layers of the Arctic Ocean to melt all of the Arctic sea ice many times over.
Toggle Commented Oct 2, 2015 on 2015 minimum overview, part 2 at Arctic Sea Ice
In a couple of days, on October 6th, the Sea Ice Prediction Network is hosting a webinar: This webinar, entitled "The 2015 Sea Ice Outlook: Post-Season Discussion" will provide discussion of the 2015 summer sea-ice conditions, a review and analysis of outlooks contributed from 2008 to 2015, and discussion of the challenges and successes of predictions at the local scale. Julienne Stroeve, Larry Hamilton and Cecilia Bitz will be speaking. Be sure to register.
Toggle Commented Oct 1, 2015 on 2015 minimum overview, part 2 at Arctic Sea Ice
This is a continuation of Part 1, wherein I posted several graphs and maps depicting the 2015 minimum, and the weather conditions leading up to it (Tamino has a great blog post showing the long-term sea ice extent trends, all of them, not just the cherry-picked, meaningless one the GWPF... Continue reading
Posted Oct 1, 2015 at Arctic Sea Ice
Hi, Pete. Yes, I noticed. PIOMAS volume will be discussed in Part 2.
Toggle Commented Sep 26, 2015 on 2015 minimum overview, part 1 at Arctic Sea Ice
Cato, my impression is that the maximum had very little influence on the melting season. I know several commenters speculated about how 1 million km2 less than 2012 at one point, would surely mean that 2015 would break the record, but it simply doesn't work that way. That million had simply vanished after a couple of weeks. A maximum can be very high because during the last 2-3 weeks of the freezing season lots of thin ice is formed at the edge of the ice pack, because of wind pushing the ice outwards and low temps freezing the leads that pop up behind the floes (probably one of the main reasons of high Antarctic sea ice extent in recent years). Conversely, a max can be low because winds are compacting the pack and temps aren't low enough to freeze the open water. But at a certain point, after the melting season has started, thicker ice is reached, and other years catch up again. In theory though, if a max is low, say because of events on the Pacific side of the Arctic, and weather conditions are conducive to melting and absorption of radiation (sunny weather, warm temps from land because snow melts fast there) the head start could be capitalized. We saw some of that happen this year during June, but then the weather switched and action on the Pacific side stalled for several weeks. And that's how it goes most of the time.
Toggle Commented Sep 24, 2015 on 2015 minimum overview, part 1 at Arctic Sea Ice
Are you prepared to speculate yet about what 2016 holds in store for the sea ice in the Arctic? I'm always willing to speculate, Jim, but it's easier near the end of the freezing season. Along the way we get an idea of MYI transport into the Beaufort Sea and out of Fram Strait, volume, thickness distribution, amount of snow on the ice, temperatures, atmospheric pressure and cloudiness (read: outgoing radiation), etc. But I agree that events in the Pacific are highly intriguing. Of course, El Niño pushing out all that heat, but also the positive PDO and that so-called Blob in the North Pacific. We'll see how the Bering and Okhotsk Seas react to that (the small amount of sea ice there at the end of the freezing season was the main reason the maximum was so low and reached so early). What interests me right now in the Arctic is the absence of spikes on the DMI 80N temperature graph. I mean, SSTs have been reasonably high this melting season (see the comparisons I did for each ASI update), but apparently this heat either hasn't been released yet or it isn't crossing the 80° boundary. The last time that it took so long for spikes to show up was in 2009. As you can see on the CT SIA graph I posted in this blog post, the Arctic Ocean is being covered with fresh ice pretty fast, and if all that heat (also brought up by turbulence, as you say, thanks for that) doesn't get dumped in the air, but part of it stays in the water, insulated by ice and snow, this might play a role next year. So, that's my speculation for now. :^)
Toggle Commented Sep 24, 2015 on 2015 minimum overview, part 1 at Arctic Sea Ice