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Comments 48301 to 48350:

48301. curiousd at 06:49 AM on 23 February 2013
       Why Choose One Textbook for Introductory Climate Change Science Courses?
       

       There is a type of couse offering with the following institutional constraints:

       1. Everything must be covered in one semester. With a week break for Thanksgiving or "Spring Break" one then has 14 weeks.

       2. Since the implications of the science are rather depressing without there being some emphasis on something that can be done, at least half of this one semester course has to be devoted to "What can be done?"  There can be strategies for teaching more than one thing at a time. Thus, the students will be barely conversant with graphs. One can show a graph of corporate average fuel economy (CAFE) in the U.S. and the students will notice fuel economy improved by about 10 - 15 years after the oil embargo in the 1970s. New gas mileage requirements were put onto car manufacturers with about a 10 - 15 year deadline. The students learn about reading a graph and that government action can do good.

       3. In the U.S. the mathematical background of such students, taking the required one semester quantitative course in a large state university, will be on average terrible. One has to teach them how to convert units. Half the class cannot do this. Thus, a problem asking the students  to go from U.S. miles per gallon to European liters per 100 km will be immensely challenging, and at least half the class will miss these problems without special training.

       My favorite innovation.....A "quarter pounder" at McDonalds  is (very approximately) a newtonburger.

       I eventually gave up talking about avogadro's number or moles. To the question ....."How many atoms of carbon are in a 6 gram diamond?" a really common answer is half an atom.

       4. There are 24 chapters to Farmer and Cook, Volume 1 alone and only 14 weeks at the instructor's disposal. So far I see  in Farmer and Cook immense  thoroughness on climate but little coverage of wind power, solar power, nuclear power, or hydropower.

       But the instructor him/herself in the U.S., teaching such a course, is likely to know little  about clmate change at all. Similarly this applies in high schools. For these people, I think Farmer and Cook is the best thing going.

        

48302. Chris G at 06:41 AM on 23 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       OK, so I live in Kansas.  It pains me when these kinds of things happen, and this is not the first time.  For instance, our govenor has declared some of the best areas for wind energy to be natural reserves; thereby, short-circuiting the approval process for the company that wanted to put windmills there. I thought this was odd because he hasn't otherwise been a big supporter of conservation, but then, this is the same government that rushed the coal plant in Holcomb through the approval process in order to get it done before the new EPA mandates took effect.

       The state is predominately Republican, and agriculture is probably the largest industry.  I think we are suffering a result of Republican group-think where they simply can't connect the dots between the economy and the environment, because that would cause them to have thoughts which would be seen as being disloyal to their group.

       I mean, the average bushels of wheat per acre for Texas is 30, Oklahoma 35, Kansas 40, Nebraska 44(?).  Not even counting an increase in extreme heat and drought events, we are looking at somewhere in the vicinity of a 25% loss in productivity as the Kansas climate becomes more like Texas.  It's mind-boggling how they can not see this as being bad for the local economy.  But, if you ask one of our politicians, Moran for example, he will tell you he does not support a carbon tax because he believes it will hurt the economy.  (Face-palm)

48303. Jose_X at 06:39 AM on 23 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       Are we to pass on word to the constituents of Congressman Dennis Hedke that he deep down believes they should not vote since each has only one vote that will have an "insignificant impact on curving" the election?

48304. Composer99 at 05:48 AM on 23 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       Clyde:

       IMO your focus on ubrew12's off-hand comment is derailing the thread.

       Drought in the US midwest is off-topic for this post. There are many other posts on Skeptical Science where attribution of dought can be - and probably already has been - pursued.

       Moderator Response: [DB] Agreed. All further replies to Clyde pertaining to drought should be placed on this thread, not here. Leave a redirect message here as appropriate. Thanks to all for your compliance in this.
48305. Don9000 at 05:21 AM on 23 February 2013
       Putting an End to the Myth that Renewable Energy is too Expensive
       

       Since the posts on this article have slowed, I want to add a comment regarding the construction of nuclear power plants, as an uncle of mine has a vast amount of experience in the field, having worked on many nuclear and fossil fuel-fired plants, and I have had many a chat with him over the years. As a civil engineer with expertise in all things concrete, he experienced a rather dramatic situation back in the mid-1980s, I believe, during the construction of a plant in the midwestern US, I think in Illinois.

       In the middle of the construction of the critical components of the plant, the government-approved supplier of the high-grade sand required for the high strength mix of concrete ran out of the approved sand (despite having supposedly proven to government inspectors that it had enough such sand in its quarry). As my uncle related the story to those of us gathered around the holiday dinner table, the ensuing delay of several months resulted in a cost overrun in the hundreds of millions of dollars, since all the workers involved in the construction operation were contractually entitled to their pay during the wait for a new source of sand to be approved.

       This was merely the biggest and most costly mistake my uncle observed. At different times he pointed out that merely pouring the concrete often involved very costly preparation work and other delays, since many variables--from the exact mix of ingredients to the ambient temperature where it was poured were specified quite exactly in order to guarantee that the concrete would meet the standards. If, for example, the weather was too hot or cold, and there was no way to warm or cool the location of the pour, concrete work had to halt, causing further delays, which in turn often caused additional cost overruns down the line.

       At other times, my uncle noted that seemingly minor mistakes or omissions in the enormously complicated plans for the phsyical buildings associated with a power plant proved quite costly. One he cited was failing to include a particular required cable bundle in the specifications which meant that a major steel beam had to be cut out and re-welded, which was nearly impossible to do while still maintaining the required tensile strength. Another happened when, out of thousands of doors spread throughout one new plant, two doors were switched on the blueprints (a sealable, submarine-style door switched places with a standard office door) and the mistake wasn't discovered till after the concrete had been poured. According to my uncle, these kinds of mistakes were rarely easy to fix--usually because of the technical challenges, but also because of the bureaucracy.

       Finally, he still laments that the industry continued to build the same basic reactor design for decades, even though better designs were on the drawing board, and then compounded this mistake (as he saw it) by instead focusing on arbitrarily changing the little things--like where to route cables or pipes or where to put offices or stairwells or windows or various control rooms, which meant that mistakes kept cropping up and that costs kept increasing, since despite using the same reactor design, his company never could say it built the same plant twice.

       
       I suppose my main point is that building wind farms and solar arrays is not nearly as fraught with such serious potential problems, and the costs of such projects should continue to come down as the builders of the hardware and the installers gain experience. This cost draw-down clearly won't be as quick to happen with the next generation of nuclear plants, as they are likely to experience a vast number of growing pains due to their much greater level of complexity.

48306. william5331 at 05:18 AM on 23 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       I hear this argument ocassionally in New Zealand where I live: that installing renewable energy systems will have an insignificant effect on the world's production of CO₂.  We are a country of 4.3 million (what is the population of Kansas) and should be doing at least our proportional part in reducing the use of fossil fuels.  In fact, since we, like Kansas and the rest of the Western world use 10 times the fossil fuel per capita as the world average, we should be doing 10 times as much.  But forget all that.  Solar panels are now down to the oft quoted $1.00US per nominal watt which puts them in contention with fossil fuels.  They are economically worthwhile to install right now.  The critical factor is the legislative framework around their installation.  The crazy subsidies that Germany and some other European countries give are not necessary.  All that is needed is a system which is fair to both the small installer and the power company.  Most important the government must not try to milk the calf.

       http://mtkass.blogspot.co.nz/2009/09/german-fit-system-brilliant.html

       http://mtkass.blogspot.co.nz/2007/10/excess-energy-what-to-do.html

       http://mtkass.blogspot.co.nz/2009/11/legislation-for-electric-cars.html

48307. Clyde at 05:04 AM on 23 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       The authors conclude that projections of acute and chronic PDSI decline in the twenty-first century are likely an exaggerated indicator for future Great Plains drought severity. Source    Here we show that the previously reported increase in global drought is overestimated because the PDSI uses a simplified model of potential evaporation 7 that responds only to changes in temperature and thus responds incorrectly to global warming in recent decades. More realistic calculations, based on the underlying physical principles8 that take into account changes in available energy, humidity and wind speed, suggest that there has been little change in drought over the past 60 years. Source

        To be clear I'm not saying GW did or didn't cause any one drought. As already stated nobody can say for sure. I thought ubrew12 might of had some new info on the matter.
       Moderator Response:

       [DB] As noted below, discussions pertaining to drought should be placed on this thread, not here. Leave a redirect message here as appropriate. Thanks to all for your compliance in this.

       Note: extensive block-quoting, as you do here, is frowned upon by the Comments Policy. Individuals here are expected to paraphrase a referent citation in their own words and include a contextual rationale as the the significance and appropriateness of the citations they furnish.

       Fixed quotation formatting.

48308. dana1981 at 02:30 AM on 23 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       curiousd @2 - as a general rule it's okay to comment on policy but not politics.  For example, 'the Republican Party is blocking climate legislation' is fine, because it's factually true and deals with climate policy and isn't a political attack.  'He opposes climate legislation because he's a Republican' is not okay, because it's purely a political comment.

48309. philipm at 00:06 AM on 23 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       Drilling a new oil well also has “insignificant impact” on energy supply, but they still do it.

48310. DSL at 23:51 PM on 22 February 2013
       It's not happening
       

       On the comment stream at Alex Knapp's Forbes blog:

       Daniel Fisher (Forbes staff): "I am not sure the debate is over whether the climate is warming – obviously it has been getting warmer since the last Ice Age, which was a very short time ago. The question is whether that increase is accelerating in a non-random way, and the acceleration is caused by the measured increase in atmospheric CO2. Does this new method help unravel that?"

       Bob Tisdale: "That would be difficult to show for a couple of reasons. First, the hypothesis of manmade global warming is only supported by general circulation models, which are known to be imperfect representations of the Earth’s climate systems. Second, that hypothesis is not supported by NOAA’s satellite-era sea surface temperature data or by NOAA’s ocean heat content data since 1955."

       Is Tisdale paid? 

48311. DSL at 23:16 PM on 22 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       Try Johanson & Fu (2009), Clyde.  Here's the abstract (emphasis mine): 

       "Observations show that the Hadley cell has widened by about 2°–5° since 1979. This widening and the concomitant poleward displacement of the subtropical dry zones may be accompanied by large-scale drying near 30°N and 30°S. Such drying poses a risk to inhabitants of these regions who are accustomed to established rainfall patterns. Simple and comprehensive general circulation models (GCMs) indicate that the Hadley cell may widen in response to global warming, warming of the west Pacific, or polar stratospheric cooling. The combination of these factors may be responsible for the recent observations. But there is no study so far that has compared the observed widening to GCM simulations of twentieth-century climate integrated with historical changes in forcings. Here the Hadley cell widening is assessed in current GCMs from historical simulations of the twentieth century as well as future climate projections and preindustrial control runs. The authors find that observed widening cannot be explained by natural variability. This observed widening is also significantly larger than in simulations of the twentieth and twenty-first centuries. These results illustrate the need for further investigation into the discrepancy between the observed and simulated widening of the Hadley cell."

48312. CBDunkerson at 22:54 PM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       If we look at the extent (length x width / concentration) trend the ice will be gone in ~20 years.
       If we look at the area (length x width) trend the ice will be gone in ~10 years.
       If we look at the volume (length x width x thickness) trend the ice will be gone in ~5 years.

       Notice how the duration shrinks as the 'completeness' of the information increases. That is, ice volume tells us about ALL of the ice while area ignores thickness and extent is area further distorted by how concentrated the ice is. All three of these trends have been accelerating AND converging. The gaps between them were much greater even just five years ago. In another five years I think they'll be in near alignment... either because they will have all hit near zero or because the extent and volume will converge on the area trend. I don't think there is any chance of the extent trend being the 'correct' one.

48313. Dikran Marsupial at 21:27 PM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       artcicio - the predictions do not assume constant thickness.  They do not take advantage of our knowledge of thickness, but that is not the same thing.  I suspect that one of the reasons for looking at extent, rather than volume is that there is insufficient historical data available, which meant that until recently, models of ice volume were too uncertain.

       Note Walt Meiers comments about the timing of an ice-free Arctic, they apply to volume just as they do to extent/area.

48314. arcticio at 20:40 PM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       These predictions assuming constant thickness ignoring actual oberservations do not even work as first approximation. Wasn't the final advice from last SEARCH sea ice outlook to include volume?

       Sea ice went from a mostly perennenial to a predominantly seasonal ice pack. Cryosat and PIOMAS both agree on meters of tickness lost North of Greenland and the Archipelago. Ice drift speed doubled in recent decades probably rendering Meier's point meaningless. Absorbing new observations the discourse moved on long ago.

       Don't irresponsibly feed policymaker with a prediction of an ice free Arctic in decades based on extent math while all other facts propose that will happen in a few hundred weeks.

       Get sceptic on the skills of a sea ice model ignoring thickness and dynamics.

48315. curiousd at 19:24 PM on 22 February 2013
       In Wall Street Journal op-ed, Bjorn Lomborg urges delay with misleading stats
       

       Comment on bchip at #7 above:

       Missing from the thread are comments on the ways the legal and political system in the U.S. impedes renewable implimentation in cases in which subsidies are not needed.

       Example:

       1. Since 1977 the price of standard crystalline solarcells has fallen by a factor of 35. This is sometimes referred to as "The Swanson Effect".  See URL http://www.marctomarket.com/2012/12/great-graphic-solar-energy-and-swansons.html

       2. But the he price of installation of solar cells varies strongly from place to place, and is much less in Germany than in the U.S. See the URL

       3.  The plummiting cost of crystalline silicon solar cells was a contributor to the Solyndra bankruptcy; and make technologically more complex concentrating solar systems less important.  See:

       http://topics.nytimes.com/top/news/business/companies/solyndra/index.html

       and:

       http://www.solarpowerworldonline.com/2012/11/business-issues-the-capitalist-case-for-solar/

       4. 

         Over half of the homes in Bangladesh lack a grid connection. But for $300 a typical off grid user can power light bulbs, a television set, and a fan by off grid rooftop solar.  

       5.  I then pose the following rhetorical question: In, say, Connecticut, although a well heeled person might construct his/her sustainable home via a combination of solar and geothermal, why cannot someone who lives, say,  in an apartment flat instead purchase solar installations for a large scale desert location in a part of the country with better insolation and receive corresponding cuts in his/her electric bill? On a smaller scale, such a concept was recently tested in California by  

       Conclusion:

        

       There is an obvious solution to this problem

        

        

       Moderator Response: [RH] Fixing font size on link that's breaking page formatting.
48316. Dikran Marsupial at 19:23 PM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Kevin, it was Phillipe's question that you ducked, so your reply should have been directed to him.  I was merely pointing out to you that if you want to take part in a scientific discussion, giving adequate answers to peoples questions and not avoiding difficult issues is generally a good idea.

48317. Rob Honeycutt at 15:38 PM on 22 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       Clyde...  It's a matter of relative chance.  It's possible you'd see such an extraordinary drought without influence from global warming.  But global warming makes it much more likely that such extraordinary doughts will occur.  

       So, you kind of have two choices.  This was an extreme occurence and unlikely to occur again for a long time, or this is a function of human induced changes in the climate system and more likely to become more frequent, or even normal.

       You choose where you're going to put your money.

48318. Chris G at 15:34 PM on 22 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       Clyde, if you want a proof, I suggest you take up theoritical mathmatics; there are no proofs in applied sciences.  There are probabilities.  Droughts have become more widespread, and in particular, 3-sigma heat waves are more than 10 times more common than they were prior to 1980.  

       So, do we know absolutely that there would not have been a drought and heat wave last year (and the year before) in the US with an atmosphere at 290 ppm? No.

       Do we know there is more energy in the climate system than there was prior to the industrial revolution?  The odds that every metric taken on that is wrong are infintesimaly small.

       What do you think is more likely, that adding energy to the system shifts precipitation patterns and results in more frequent high temperatures, or that adding energy to the system has had no effect?

48319. Clyde at 15:11 PM on 22 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       ubrew12 says - The bizarre truth is that Heartland farmers in Kansas are only now in business thanks to 'Big Government'-backed farm insurance programs that tax the ordinary American to help them through their global-warming-induced drought.

       
       Wheres the proof GW caused the drought?
       

48320. Rob Honeycutt at 15:01 PM on 22 February 2013
       Mars is warming
       

       Novemdecillist...   Is there something to give you indication that others are not thinking outside this particular box?  I would suggest that scientists have made careers out of looking into a wide range of boxes to see if there could possibly be other explanations for what they see.  In fact, other planets warming would be one of the first in a long series of other boxes researchers would check into.

48321. stressedchef at 14:51 PM on 22 February 2013
       Climate's changed before
       

       Another aspect of the "climate has changed before" argument, not covered off in the current answer, is the implication that current climate change should not be considered alarming. "It's changed before, and yet here we are" may be a fair summary of this version.

       Is it worth adding some relevant discussion and cross-filing the argument under both the "It's not us" and "It's not bad" taxonomies?

       The main responses seem to me to be that a) deep past climate changes were not much fun for living things at the time, being associated with mass extinctions and great upheaval; b) human societies and economies are adapted to the climate they developed in, and so even changes within the range of natural changes of the distant past would be very disruptive; and c) humans now use a very high proportion of potential quality farmland, affordable freshwater and so on to accommodate a large population with high (for many) or rising (for many) living standards; there is not much safety margin  to prevent a loss of living standards if climate change erodes availability of some of the resources we depend on.

48322. curiousd at 14:03 PM on 22 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       In post 2 above I should have said solar enterprises for CO2 offset, not solar offset enterprises.

48323. curiousd at 14:00 PM on 22 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       Question.....I personally tend to agree with ubrew12 in post 1.  But what is the deal about political posts in SKS anyway? After several months of research into solar offset enterprises I found that if you go from charities to small businesses to various investment strategies, all are largely controlled by laws and politics. In SKS I feel I must not be too specific, but in essence I became convinced that at least in the U.S. the main impediments to large scale use of  renewables are to be found not in our technology, but in our form of government.  SKS is by good reason non political, and though I do understand why a line must be drawn, I am now somewhat confused about where that line is drawn. 

48324. rehuie at 13:05 PM on 22 February 2013
       In Wall Street Journal op-ed, Bjorn Lomborg urges delay with misleading stats
       

       Another major problem with the use of GDP is how impacts on it are used. There appears to be a fundamental assumption of linearity. That is, if agriculture is 10% of the GDP, and agricultural yields are reduced by 10%, the GDP takes only a 1% hit. This is probably correct for small changes. But if the changes are large, this is clearly not correct. If agriculture takes a 20-30% hit, then the folks who generate the other 90% of the GDP are going to be spending most of their time looking for food, so the GDP takes a much larger dive. This is but one small example – I’m sure others can generate more.

48325. KR at 12:05 PM on 22 February 2013
       Mars is warming
       

       Also worth noting are the astronomers - who spend their careers looking at the stars, including spectral and intensity measurements. If we had entered a nebula (that was somehow unobserved at a distance) the reduction in starlight over the last 40 years would have been quite noticeable. Not to mention spectral changes in sunlight, measured either from the surface or from satellite. 

       Given a complete lack of evidence for a hypothesis of interstellar dust/climate interaction, I would classify it on the same level as "climate elves". 

48326. ubrew12 at 11:34 AM on 22 February 2013
       Low emissions are no justification for Kansas scaling back renewables
       

       There's a groundbreaking book in American politics, Thomas Franks 'Whats the Matter with Kansas?', that helps explain what is going on here, "where small farmers cast their votes for a Wall Street Order that will eventually push them off their land".  Where former lobbiests for tobacco grower Phillip Morris joined hands with the Koch Brothers to create a 'Heartland' American Astroturf movement of 'Salt of the Earth' dupes.

       The bizarre truth is that Heartland farmers in Kansas are only now in business thanks to 'Big Government'-backed farm insurance programs that tax the ordinary American to help them through their global-warming-induced drought.  And, thanks to 'Heartland-values' propaganda, they then USE their solvent status to proselytize against those very 'Big Government' programs, and the Climate Change 'nonsense' they would otherwise seek to redress.

       "We're not in Kansas anymore, Toto"

48327. scaddenp at 11:25 AM on 22 February 2013
       Mars is warming
       

       And also worth noting (as this and articles on other planets show) that real evidence for climate change on the other planets is somewhat lacking. See the intermediate versions.

48328. Tom Curtis at 11:02 AM on 22 February 2013
       Mars is warming
       

       Novemdecellist @33, there is a very simple reason to think that our motion through the galaxy has very little do do with current changes in climate.  Specifically, it will take us 1360 years to travel just one light year at our current rate of travell.  In the direction we are travelling, there are no nebulae to obscuring local stars, so we know the nearest nebula to be many light years away.  Apparently the nearest nebula of any sort, L134, is around 300 light years away, and not in our direction of travel.

       It follows from this that the radiation, and molecular density of the space through which we are travelling has not changed appreciably in hundreds of thousands of year; and will not change appreciably for hundreds for thousands more years except in the cases of nearby supernovas.  And if it is not changing, it is not the cause of change.

48329. Novemdecillist at 11:00 AM on 22 February 2013
       Mars is warming
       

       We have NOT been measuring the other planets temperatures systematically since the 70's.... and I did not state the the majority of EARTH warming does originate with our mismanagement of the planet.  I was only stating that IF other planets in our system might all be experiencing warming, then we should  look at other possibilities be they "weird" or undiscovered! 

48330. scaddenp at 10:14 AM on 22 February 2013
       Mars is warming
       

       Whether travels on the galactic path had anything to do with past climate change is harder to decide, but we can see clearly that it has very little to do with post-1970 climate change. Why? because we have good measurements of the climate determinants. The only "space" factor affecting climate is TSI, whether from change of angle, change of solar luminense or "space dust". This is accurately measured by satellites since 70's and is stable if not decreasing (see "its the sun" argument), and yet the earth warms. Why look to weird, unknowable, out-there sources of warming when there is a perfectly reasonable, physically plausible solution coming right out of the smoke stack? Or to put it another way, we have measurably increased the energy flux onto the surface of the earth with increased GHGs. What mechanism do you propose by which this would not cause warming?

48331. Novemdecillist at 09:35 AM on 22 February 2013
       Mars is warming
       

               Thinking 'outside the box' is a school not often visited by some.   In all the discussions of planetary global warming (i.e.  Earth, Mars Jupiter, Saturn, Pluto) very little attention is given to our solar system's travel above, below, and around the galactic plane on its cyclical route round the Galaxy. (approx 240k+ years).  Conditions along the path are hard to predict since historic records are only now being established.  Therefore any theories or calculations of planetary temperatures from volcanic, atmospheres, rings of dust, or human intereactions, etc. must include calculations of the density and  position of materials encountered along our solar systems path and its interactions with the Sun's activities.  These conditions make it extremely difficult to predict any astronomical algorithm's absolute forecasting the reason for Earth's warming trends.  In other words,  the best thought humans put forth probably has not reached a definite answer in totallity to the question, "Why is Earth warming?" 

48332. Roger D at 09:04 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       My "prediction" is 4.2million Km2, based on cheating, i.e. putting a straight-edge up to the computer screen, and eyeballing a vertical line through Gavin Crawleys prediction line in Fig. . The intersection for 2013 minimum is ~4.2 million Km2 (with a low of ~3.2 and a high of ~5.1 million Km2)

       Given that Gavin's predictions have proven better than average, and also that there is an ongoing trend of less multi-year ice (oops, sorry Steve Goddard, I mean an ongoing trend of  "increasing extent of Jan-Sept. ice growth") it doesn't make any sense to choose something like 5million Km2 as a likely ice extent, and then put an error bar on that.

        

48333. Bob Wallace at 08:54 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Keith #43 - my observations and expectations match yours.

       I have a small pond outside my living room window that freezes to 100% extent and melts to 0% multiple times per year.  After being frozen over for days, it goes from almost frozen over to ice free in short hours.

       The Arctic sea ice has gotten (comparatively) very thin.  A few decades back the Russans set up their ice observatory stations on 20'/6m thick ice.  Now they report that they have to hunt for 6'/2 meter ice.  And they have to be prepared to move quickly if that ice begins to break apart.

       I think that in the next few years we'll see a rapid melting of first year ice and that will clear the Fram and CA channels for the last remaining multi-year ice to be flushed out of the Arctic.  I won't be surprised to go from significant extent to "Where's the ice?" in less than a month.

        

48334. dana1981 at 08:40 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Note that the summer storm had a small impact on the 2012 Arctic sea ice minimum.  There almost certainly would have been a record even without the storm.

48335. Djon at 08:39 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Kevin,

       
       Following your suggestion, when I look at figure 2 I see:

       - 1986 more or less matches your description, apparently fully recouping the loss that occurred in 1984 and 1985.

       - 1992 followed a year of recovery not loss, and 1992 alone didn't have a recovery as large as the preceding two loss years, 1989 and 1990, put together

       - 1997 was a year of loss rather than recovery.  You presumably meant 1996, not that it recouped two immediately preceding years of loss either.  If I were in a generous mood, I guess I'd allow that 1996 recouped the two years of loss that occurred in 1989 and 1990, though I don't see how that helps your argument that the losses of last year should be expected to be recouped this year.

       - 2001, like 1992, followed a year of recovery.  Unlike 1992, it looks as though the 2001 recovery was about the same size as the preceding two years of loss put together.

       - 2006 didn't recoup the loss in 2005, let alone the loss of 2004 and 2005 combined

       You're failing to convince me that any careful analysis underlies your beliefs about sea ice.

48336. cRR Kampen at 08:30 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       #43, Keith - that is my point exactly. This is why catastrophe theory applies, and not gaussian thinking. Even my hypothesis on the evolution of arctic sea ice these years is based on the same sort of observations re canal, pond and lake ice.

       That hypothesis dates from 2005 and predicted first arctic ice free summer at +10 to +15 years, which means I can seriously fail this year or next.

       The prediction was based on the miracle Britain-sized hole appearing in the north of the East Siberian Sea in August '05, in an area where for centuries to many millenia a massive 2-4 metres ice, usually affixed to the Siberian coast including during the minimum, was the norm.

       I am actually quite aghast at the amount of underestimation of this process even in (semi-)professional circles.

48337. cRR Kampen at 08:20 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       #40 Tom, I am aware of that. The question is: what do we mean by 'the mean' here? Obviously we do not mean the 1979-2000 ice extent/area/volume mean for this number has (literally...) no meaning anymore. Therefore expectations based on this regression concept for 2013 running a higher minimum than 2012 are rather gratuit.

       As for the discussion on error bars, as of this year one side of such a bar is very easy to place: it is on the zero of the vertical axis.

48338. Kevin8233 at 07:16 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Dikran,

       Some of the other reasons,

       1.  2012 was warm

       2.  2011 was warm

       3.  etc

       4.  Put several years together in a row that were warm and the logical deterioration of the thickness of the ice occurs.  Look at the trend for ice volume.  All of these things point to a decreasing ice extent, my point was that the storm was a major cause (not saying the only) for it to be lower than expected.  Looking at the "professionals'" predictions, they were all above the actual, so obviously they thought the actual was exceptional as well.

       Looking at fig2, you can see several recovery years that do recoup a couple of years losses - these do not portend a general recovery of the overall trend - nor am I implying that - look at years 1986,1992,1997,2001,and2006.

48339. KR at 06:25 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Ok, I'll throw a few cents into the ring, based on a simple polynomial extrapolation (R² = 0.8194).

       • 4.04 Mk^2 +/-0.8 (2σ) extent
48340. scaddenp at 06:19 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       I'll go with 4.1 +/- 0.9, error bars based on variability, number on crude extrapolation.

       Got to ask Kevin - if it goes below 4, what conclusions are going to draw? What sort of data is required to change your mind? At the moment, I would say 5 is "Math You Do as a "skeptic' to Make Yourself Feel Better", and as likely to be as accurate as Rove.
       

48341. Djon at 06:12 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       If you wanted to say my error band was nonsensical, just say so. I think your unwillingness to have your understanding of what is likely to happen to sea ice extent in the next year judged based on your error band is a much more convincing demonstration that your error band is nonsensical than my simply saying so.  Just because you don't like being mocked for writing nonsense isn't a good reason to retire mockery as a debate technique.
48342. keithpickering at 05:12 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Personally I'm skeptical of all statistical methods to predict SIA. I say this based on my personal observation over decades of the way ice melts on the lake behind my house. The area of the ice is extremely non-linear during ice melt. During the winter, ice covers 100% of the lake. During spring, as the weather warms, the ice still covers 100%, because it's melting mostly from the bottom up. At some point the edge gives way to open water, and the covered area is 99% to 98%. And then, in about a day, it goes from 97% to zero, as the ice is no longer thick enough to withstand the wind.

       We're seeing basically the same fall-off-the-cliff behavior in the Arctic, starting in the Kara Sea and working east. Last year it made it all the way arount to the Beaufort, and it will again this year too (although at even higher latitudes).

       If you want to know when summer ice will hit zero, ignore extent and look at the volume. Ice melts from the bottom up.

48343. Dikran Marsupial at 05:09 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Kevin, well quite, which is one of the reasons that your very confident prediction of a record September recovery seems somewhat peculiar.

       
       By the way, in this post, you ducked the question posed by Phillipe here.  He asked you to list the "number of factors" [note plural] involved in last year's record other than the storm that had already been mentioned.  Pointing out that "that [the storm] was "one" of the other reasons" suggests you either didn't read his post with sufficient assiduity, or that you were being deliberately evasive.  Please could you answer the question, so that we can understand your reasons for your prediction.
       

48344. Kevin8233 at 04:59 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Dikran (35):

       That is what I was trying to say, it is easy to set a re-freeze record when so much melted previously.  The re-freeze record is not indicative of a new trend, as you point out, the new max is still less than the previous max.  I was not trying to state otherwise.

48345. Tom Dayton at 04:57 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       cRR Kampen, there is no "physics" behind regression to the mean. Regression to the mean is a human perceptual/judgment of the mathematical fact that (by definition of the mean) observations are more likely to be closer to the mean than farther from it. When observations are independent of each other, an observation happening to be far from the mean does not change the probability of the next observation most likely being closer to the mean than farther from it.  The human perception/judgment of those two observations is that the second observation moved toward the mean (regressed toward the mean).

48346. Kevin8233 at 04:56 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Djon,

       I did not expand my error bars.  the +/- 4.5 is 5 times Tamino's error band.  Since you want to place a consequence to my being wrong, I suggested using Tamino's error band.  Maybe you would prefer to use his band without multiplication? (5.0 +/-.9)   If you wanted to say my error band was nonsensical, just say so.

        

48347. Djon at 03:51 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Kevin,

       
       Do I have to have made a prediction for your prediction to be wrong?  In school, did you complain to teachers who gave you a bad grade on a test because I hadn't taken the same test?  Maybe, unlike you, I'm not overconfident enough to think I can predict the sea ice minimum to within +/- 100,000 square kilometers seven months in advance.  Although "overconfident" doesn't seem like the right word since you don't seem willing to stand by your prediction, judging by your apparent desire to expand your error bars from +/-0.1M to +/-4.5M.

48348. Dikran Marsupial at 03:33 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Kevin, I'm sure Tamino would concede that his prediction was falsified if the observations were outside his stated error bars.  There is a good reason why Taminos error bars and mine are much broader than yours, which is because that is the basic scale of inter annual variability around the trend.

       I suspect Djon was being lenient as the error bars on your prediction are clearly unrealistic, unless there is something fundamental that you know about Arctic sea ice that the rest of us don't know (including the scientists who work on this for a living).

48349. Kevin8233 at 03:26 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Djon,

       How about 5 times Tamino's error band.  That would make it 0.5 to 9.5 million Km^2.

       Where is your prediction? 

48350. Dikran Marsupial at 03:22 AM on 22 February 2013
       2013 Arctic Sea Ice Extent Prediction
       

       Kevin, see figure 4, there was indeed a record gain in Arctic sea ice this year, but the January sea ice extent was still lower than last year nevertheless, so the trend in winter extent is still downwards.

       The fact that the record gain is very likely to be simply due to the record loss last year is exactly why Goddard and Watts are wrong, it is exactly what would be expected, and doesn't signal any kind of recovery of sea ice, because the extent itself is still on the decline even with a record gain.

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