Last week, NSIDC scientist Andrew Slater died unexpectedly. It goes without saying that the news shocked me, and I wasn't the only one (here's the memorial web page).
I had never met him, although we mailed once or twice in the past year. He also occasionally commented on the Arctic Sea Ice Forum, to chime in or explain one thing or other about some of the work he did.
Most of all, I increasingly used images and graphs from his wonderful personal website, for blog posts and on the Arctic Sea Ice Graphs website, that features several of his graphs on the front page.
I guess that's why the passing of this near-stranger really struck me emotionally. The fact that a scientist would spend so much of his energy and own time to freely share all that info and visualized data, not just for fellow scientists via the peer-review process, but for the lay public as well, on a website chock-full of near-real time graphs (snow cover, sea ice, model forecast)...
It's invaluable. It really says something about a person.
Speaking of model forecast, here on the blog and on the forum, people continuously referred to Slater's model, which over the years performed really well in the SIPN Sea Ice Outlooks:
A couple of days ago a paper was published in the journal Revista de Climatología by Diablobanquisa, a Spanish blogger who regularly writes about Arctic sea ice on his blog. In this paper Diablobanquisa, together with his co-author, presents a new time series of September Arctic sea ice extent, including data for the Siberian sector. I think the work looks very solid and gives us an improved view of pre-satellite Arctic sea ice.
Below is the English abstract of the paper, preceded by the graph showing the results of the new time series (updated up to 2015):
Since 1979 satellite-borne passive microwave sensors have provided a continuous and consistent record of Arctic sea ice extent. This record shows a significant downward trend, particularly at September, when Arctic sea ice reaches its annual minimum. Records before 1979 exist, but are not consistent with the satellite record and have limited reliability, specially before 1953. We present a new time series of September Arctic sea ice extent from 1935 to 2014 that includes data for the Siberian sector (AARI operational charts) not used previously in the Arctic wide existing time series (Walsh, HadISST). The new record has been adjusted to be consistent with satellite data. The trend for 1935-2014 is -3.5% decade, while the trend for the satellite era is -13.3% decade. However, the trends since 1935 until early 1980s are positive and statistically significant. The trends turn negative in the 1990s, reaching statistical significance from 2006 onwards. The lowest annual minimum in the pre-satellite era is higher than any annual minimum after 2001.
Median September Arctic sea ice extent for the lowest decade of the pre-satellite era (1935-1944, left) and for the lowest decade of the satellite era (2005-2014, right):
Methodology and several graphs comparing the results to previous work, can be found over on Diablobanquisa (Spanish version including conclusion here). There's also a separate thread over on the Arctic Sea Ice Forum.
Congratulations and thank you, Diablo + co-author!
Today is the winter solstice. If you live on the Northern Hemisphere of our planet Earth, today is the shortest day of the year. In a sense it's the start of the countdown towards a new melting season, with the Sun slowly creeping northward a bit every day, although the sea ice still has a couple of months to expand and thicken some more, of course.
Most of you who are interested in the Arctic, probably know that during the 2015 AGU Fall Meeting NOAA put out its annual Arctic Report Card. The report contains a lot of details on everything concerning the Arctic in 2015, and that mostly means melting. Melting sea ice, melting glaciers, snow cover loss, etc., and the consequences thereof.
There's a very good article by Yereth Rosen on the ADN Arctic Newswire website, and Robertscribbler also put a blog post up today, but if you want a quick, visual summary, there's this video that NOAA put out last week:
Some other news concerning the Arctic that received traction in the media lately, is this new paper by Yeager et al. that was published in Geophysical Research Letters two weeks ago. Its title Predicted slowdown in the rate of Atlantic sea ice loss lacks the nuance that what is actually meant is winter sea ice loss, but it's explained in the rest of the text. Strangely enough, a paper by the same authors also appeared on the Nature website last week in which the nuance is omitted entirely, in both title (Possible pause in Arctic sea-ice loss) and text. Then again, the rest of the text is behind a pay-wall (edit: never mind, I have been informed that it's just a reference to the GRL paper, not a paper in itself).
Either way, the theory is that a weakened Atlantic Meridional Overturning Circulation (AMOC) will prevent warm Atlantic waters from going deep into the Arctic, and thus in winter sea ice will expand. See this informative Science Codex article for further details and quotes from the paper's researchers, such as this one:
Despite this being the second melting season that rebounds from the spectacular sea ice loss event of 2012, there have been some notable events that characterize this melting season. We may have already become used to these events, but may do well to remember that they were much rarer before 2007.
Take for instance, the Northern Sea Route that has opened up completely yet again, for the 7th year in a row. Shipping has been increasing there from year to year, and this year will probably be no different, given the following forecast for sea ice conditions in the second half of the navigation season:
Things look less easy in the Northwest Passage, where the main passage will probably remain closed again this year (after being open in 2007 and 2009-2012), although several yachts are making it through the southern route, such as Le Manguier (hat-tip to @arcticio):
But this year's main course is the sea ice in the Laptev Sea. Literally.
In previous melting seasons we had already witnessed a pronounced retreat of sea ice in this region of the Arctic. The event was quickly dubbed 'Laptev Bite', because that's what the open water grabbing its way towards the Pole looked like. But this year it's more than a bite. It's much wider and further into the pack, further than I have ever seen it go.
Arcticio sent me this animation that shows the progression of the retreat during August:
Here's a question I received some time ago from a reader of this blog who is in the process of writing a novel. I thought it'd be a nice way to pass our time while we wait for the latest PIOMAS update. My answer is basically the either/or image on the right, but maybe you come up with other ideas.
The question:
I am working on my first novel and want to check on the scientific validity of an idea: If an object were left on the ice near the North Pole how long could it conceivably remain frozen in the ice?
I know that the ice at the North Pole is different than land based ice. Whereas land based ice can reach thicknesses/depths of thousands of feet and exist for tens or hundreds of thousands of years, the ice at the North Pole is only two to three meters thick. I’m sure there is some melt or erosion on the bottom of the ice, and ocean currents keep the cap in constant motion moving ice from the center of the cap to the edge of the cap where it presumable melts or breaks off in the spring and summer. Both of these factors, and more I’m sure, affect the age of the ice at the North Pole.
So although my object could remain frozen in Greenland or Antarctica virtually forever there is a plausible time frame that it could remain frozen at the North Pole. My object would have been left on the ice circa 1800.
This is only indirectly linked to Arctic sea ice, and something I found out today, but a little over two months ago emeritus Professor of Physics at the University of Colorado at Boulder, Albert Allen Bartlett, passed away at the age of 90.
Bartlett was famous for the following quote: "The greatest shortcoming of the human race is our inability to understand the exponential function." This quote was part of a talk called Arithmetic, Population and Energy that he gave 1,742 times in 49 states and seven other countries. At the time, back in 1969, when Bartlett first held his talk, world population was about 3.7 billion.
“Arithmetic, Population and Energy” to a group of CU students on Sept. 19, 1969, the world population was about 3.7 billion. He proceeded to give it another 1,741 times in 49 states and seven other countries to corporations, government agencies, professional groups and students from junior high school through college. - See more at: http://www.colorado.edu/news/releases/2013/09/09/cu-boulder-campus-mourns-death-longtime-celebrated-physics-professor-al#sthash.Bxefv8Ja.dpuf
You might have been behind one of the 5 million views on Youtube, but if you haven't, I highly recommend watching the talk, appropriately called "the most important video you'll ever see":
People like Bartlett produce people like Bartlett.
The greatest shortcoming of the human race is our inability to understand the exponential function.” - See more at: http://www.colorado.edu/news/releases/2013/09/09/cu-boulder-campus-mourns-death-longtime-celebrated-physics-professor-al#sthash.Bxefv8Ja.dpuf
“The greatest shortcoming of the human race is our inability to understand the exponential function.” - See more at: http://www.colorado.edu/news/releases/2013/09/09/cu-boulder-campus-mourns-death-longtime-celebrated-physics-professor-al#sthash.Bxefv8Ja.dpuf
“The greatest shortcoming of the human race is our inability to understand the exponential function.” - See more at: http://www.colorado.edu/news/releases/2013/09/09/cu-boulder-campus-mourns-death-longtime-celebrated-physics-professor-al#sthash.Bxefv8Ja.dpuf
I'm supposed to be on a holiday and should let this one slide, but it's too much. I was expecting fake skeptics to remain mostly silent in face of the ice massacre up north, but apparently they acutely sense how big this blow is to the remaining shred of their credibility, and so they upped the ante of misleading and distorting stupidity. Anyone can see and judge the silliness of paid shill Marc Morano, 5-sentence posts regurgitator/vomiter Steve Goddard and of course WUWT. But this Sunday Times article, written by well-known pseudo-journalist Jonathan Leake (search for his name on Deltoid) had a quote by presumed scientist John Christy that really got my hackles up:
Professor John Christy director of the Earth System Science Centre at
the University of Alabama in Huntsville, said the Arctic had indeed
warmed, but there was also anecdotal and other evidence suggesting
similar melts from 1938-43 and on other occasions.
"Climate change is a murky science", he said. "To some it's an easy
answer to say it's due to extra green house gasses. To the rest of us,
separating natural variability from human impacts remains a wicked
problem."
Commenters over at Skeptical Science quickly took this nonsense apart. First FrankD:
Danske Meteorologiske Institut published a series of annual reports
on arctic sea ice covering most years from 1893 to 1956. The link has
one folder per year, with each containing individual pages (month
identified by the trailing digit) and the whole annual report (about 5
meg each).
Just referring to August extent...
Its true that ice extent was lower in the 1930s than it had been in the
preceding 30 years. In particular, 1938 saw a dramatic reduction from
the previous years - it was probably 1.4 M km^2 below the then long term
average and maybe 0.6 M km^2 below the already low years in the late
30's (carefully measured using Eyeball, Mk I).
So, it is fair to say there were some big melts in the 30's. But Christy's false equivalence is an epic fail - "similar melts" is pretty nice weasel-wording for mine. 1.4 M km^2 below recent climatology? Considered like that, 1938 was like 2010, I guess.
But in absolute terms, August 1938 extent was much greater (4 M km^2?) than today. So any attempt to conflate the two is...well...I can['t think of an adjective suitable for polite company.
Taking the Kinnard graphic - the 1930's "similar melt" is the second last dip on the graph, the first decline with modern observational data. This saw a return to "normal" after a peak that had seen the greatest extents in 500 years.
Compared to the current decline on Kinnard (even without "enhancement")? Well, even on Sesame Street they could tell you when one of these things was not like the other...
The sea ice is leaving us a bit more every year. It's time to start contemplating its absence, which is why I teamed up with Kevin McKinney to write an extended version of the shorter piece you might see pop up here and there. Because you know, disappearing sea ice isn't without consequences. And that's why it shouldn't leave you cold.
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Why Arctic sea ice shouldn't leave anyone cold
The first world in ancient Norse mythology, Niflheim, sounds just like the Arctic ice. Its snow- and ice-melt gave rise to the frost giant Ymir, from whose body the whole cosmos was formed. Today, science tells us a different story about the sea ice, but in that story, too, the ice is far older than humans. According to Polyak et al. (2010):
…sea ice became a feature of the Arctic by 47 [million years before the present], following a pronounced decline [in carbon dioxide concentrations]… Ice was apparently most widespread during the last 2–3 million years, in accordance with Earth's overall cooler climate.
Since modern humans are just 200,000 years old, the ice might as well be eternal.
But not unchanging. We live in that part of an ice age that is termed an interglacial, when some of the ice retreats in summer. During modern human history the ice cap has melted back each summer as Earth tipped toward the sun, then grown again with new freezing as the year turned toward the Winter solstice.
I had seen his name here and there when researching one thing or other, but never realized that Norbert Untersteiner was such a giant in sea ice physics. Below is the entire text I copied from the University of Washington's Polar Science Center website:
In memory of Norbert Untersteiner (1926-2012)
The Arctic is losing its sea ice. Today Arctic research lost one of its giants. Norbert Untersteiner passed away on March 14, 2012 at home with his wife Krystyna and son Lukas at his side.
Reports about changes in the Arctic are all over the news. Norbert wasn’t a friend of the media frenzy around every new record. However, it is hard to imagine any serious scientific assessment of these changes without encountering the work of Norbert Untersteiner.
Norbert is the father of modern day sea ice physics. He was the station leader of the 1957 International Polar Year Arctic drifting station Alpha, the first manned drifting ice station conducted by the West. This experience informed and inspired Norbert’s leadership of the Arctic Ice Dynamics Joint Experiment (AIDJEX) in the early 1970s. This was truly pioneering research that required an ambitious field campaign with up to four manned camps on the drifting pack ice. It paved the way for subsequent numerical models of sea ice used in modern climate models which are used today to predict and understand global climate change. At the conclusion of AIDJEX, Norbert formed the Polar Science Center (PSC) at the University of Washington. As the Director of PSC from 1981-1988 he inspired the thoughtful integration of logistics, observations, and modeling, used by PSC in advancing Arctic research for more than 30 years.
I saw this news item in the blog news feed in the right side bar and thought it was worth a post. From the BBC website:
Arctic 'tipping point' may not be reached
By Matt McGrath Science reporter, BBC World Service
Scientists say that current concerns over a tipping point in the disappearance of Arctic sea ice may be misplaced.
Danish researchers analysed ancient pieces of driftwood found in Northern Greenland which they say is an accurate way of measuring the extent of the ancient ice loss.
Writing in the journal Science, the team found evidence that sea ice levels were about 50% lower than today when temperatures warmed around 5,000 years ago.
They argue that a tipping point under current scenarios is unlikely, as changes to wind systems can slow down the rate of melting.
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