From the University of Calgary Utoday:
Melting Arctic ice cap at record low – By Heath McCoy
Think of a poor hamster on a spinning wheel, caught up by momentum and unable to stop until it’s overwhelmed, sent tumbling, crashing out of control inside.
That’s the analogy John Yackel, head of the department of geography, makes when he considers the annual summer ice melt in the Arctic, which he’s been closely monitoring for the past 15 years – documenting the ice cover as it’s steadily shrunk in the wake of Arctic and global warming.
Thoughts of imminent crashes seem particularly ominous this year as last week marked the unofficial peak, or the end of the summer ice melt, with ice levels more dramatically diminished than at any time since satellite monitoring began 33 years ago.
The previous record low for Arctic sea ice extent, set on Sept. 18, 2007 with a 4.17-million sq.-km. ice cap, was already shattered by the end of August this year when it had melted to below 4-million sq. km.
“This is the smallest minimum ice extent we’ve ever had, and not just in the satellite record, but probably in the last million years,” says Yackel, a sea ice geophysicist and climatologist.
From the patterns he has observed, this year’s extreme melt could be the beginning of a frightening trend.
Yackel and the university-based Cryosphere Climate Research Group use satellite technology to research the physical properties of Arctic ice. As recently as the 1980s, most of the ice in the Arctic Ocean was “multi-year ice,” – thick ice that would remain throughout the summer. At that time, the split between multi-year ice and seasonal ice – ice that would melt away in the summer – was about 80 per cent multi-year and 20 per cent seasonal.
“In the last 20 years we’ve almost gotten to the point where we’ve reversed that ratio,” Yackel says, predicting the ice extent that covers the Arctic Ocean “is likely to be gone in the summers within the next 20 to 25 years, if not sooner.”
The depleting ice cover would have serious ramifications for the planet. Arctic ice acts as a reflector of sunlight, helping regulate the Earth’s temperature, cooling the climate.
“When there’s no longer that sea ice below the air mass and it’s just open ocean, that’s when more moisture off the ocean’s surface gets into the atmosphere and the water vapor in the atmosphere makes for more violent storms,” says Yackel.
“We can also expect to see an increase in storm frequency and storm intensity for most of the world’s populated places as the Arctic and Earth continues to warm.”
David A. Evans says:
September 29, 2012 at 7:43 am
This is an attempt to baffle with bullshit. – in response to my information about ice being a poor insulator. Gee, I didn’t know that providing the U value of ice compared to insulators was baffling with bullshit. Is that your standard way of dealing with data-based comments that refute your position? Since Tim Folkerts commented at length on this, I won’t comment further.
You said: It’s not at all strange, never said it was, happy you admit that as you’ll find out.
Actually, you did say that, on September 26, 2012 at 12:13 pm: Strangely, the water under the ice is warmer and not exposed to allow either radiative or conductive energy loss.
You said: Except of course, they aren’t at the same temperature. Has the Kelvin scale escaped your notice? No, I’m fully aware of the Kelvin scale and agree that the slightly warmer water will radiate more skyward than ice. But that is mitigated by the fact that water has lower reflectance than sea ice, per the paper I cited earlier.
I said: …you seem to be implying that open water conducting/convecting heat into the air near the surface is a good thing. In fact, it is not – it’s the temperature differential between Arctic air and lower latitude air that drives the jet stream. A smaller differential means a weaker jet stream, which in turn means more erratic weather. To which you replied: Now you’re just making shit up.
Once again, you reply with another rigorous scientific refutation of my statement * sarcasm*. How do you think our weather happens? Magic? Happenstance? I’m sure you’ve watched the weather news before and heard of summer heat waves finally breaking due to Arctic air coming down, so clearly the Arctic climate has some influence on the weather we experience in the US. Here is one paper on the impact of increased Arctic temperatures: http://www.agu.org/pubs/crossref/2012/2012GL051000.shtml
From the abstract: “These effects are particularly evident in autumn and winter consistent with sea-ice loss, but are also apparent in summer, possibly related to earlier snow melt on high-latitude land. Slower progression of upper-level waves would cause associated weather patterns in mid-latitudes to be more persistent, which may lead to an increased probability of extreme weather events that result from prolonged conditions, such as drought, flooding, cold spells, and heat waves.”
Feel free to post papers or studies that support a counter position – otherwise you are the one that’s just making shit up.
As to the university degree point, it sucks that your employer doesn’t value actual experience and skills over a piece of paper.
Update on the rate of change graph:
http://i49.tinypic.com/xudsy.png
Clearly shows the re-emergence of the cyclic pattern and end of the continued and accelerating melting that occured between 1997-2007.
All available data was used up to sept 2011 but the broad filter window cannot provide a result up to the end of the period ( no Mike’s Nature Tricks were employed) . The shorter filter gives a bit more information at the end.
Despite the recent peak that did provide some recovery, the cycle average is still below zero, so there is still a smaller underlying melting trend comparable to early 90s.
Looking directly at rate of change gives us a better idea whether it’s melting recovering than trying to infere it by looking at a plot of ice coverage.
Looking at all the data tells a very different story from cherry picking one day per year and ignoring changes in the rest of the year.
To Anthony Watts,
Thanks for running this piece. I happen the think that most remarkable and most damaging change about to occur in the next decade or two will be the loss of our Arctic Sea Ice in the NH summertime. Measurements suggest that this change is about to occur by the time my young grandchilden graduate from college.
This change will cause enormous additional warming on top of that which is already occurring due to GHG-based changes. Imaging changing the Arctic from an ice-covered place to an open ocean. Ice reflects about 90% of incoming sunlight back out into outer space while an open, ice-free ocean reflects only about 10%. In the NH summertime when the NH is tilted towards the Sun so that the entire Arctic region is exposed to sunlight all day long for several months, there will be a lot more solar radiation being deposed onto our planet.
The only positive aspect of this looming problem is that it’s occurrence and easier-to-understand scientific basis just might finally cause our leaders to admit that planet Earth has a big problem – and thereby not be so easily fooled and misled by the enormous forces behind our continued use and even continued development of fossil-fuel sources of energy.
” Ice reflects about 90% of incoming sunlight back out into outer space while an open, ice-free ocean reflects only about 10%. ”
Sort of …
1) Sunlight shining straight down only reflects about 10%, but that number increases as the angle decreases. Light on smooth water at 80 degrees reflects about 40%, increasing to 100 % at 90 degrees. (But water is rarely smooth, which has the effect of reducing the effective angle and reducing the reflection.) I suspect that the number is closer to 20% averaged over the Arctic (which is still way less than the reflectivity of ice).
2) The Arctic is often cloudy, in which case the surface has little effect. Yes, the sunlight that does get thru will get absorbed better by water, but that will not be anywhere near the full insolation.
P. Solar,
That is a thought-provoking graph. On the one hand, there seem to be a cyclic pattern with a period of ~ 5.4 years. That pattern is interrupted from about 1997-2005, but seems to be re-forming. That might suggest that we are “getting back to normal” after a decade of unusual drops in ice extent.
On the other hand, that pattern is not all that strong. There are three peaks that fit pretty well, but 2 that don’t. And there is no a priori reason to expect a 5.4 year cycle. If it was an 11 year cycle, I could image it was related to the sun spot cycle. If it was two years, I could image some sort of annual feedback, where small ice one year drives large ice the next (for example, more open water one summer allows more effective cooling, leading to more ice the next year). But 5.4 years seem a rather odd period with no obvious driver. A weak correspondence with no theoretical foundation makes me a bit skittish.