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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 40551 to 40600:

  1. A Miss by Myles: Why Professor Allen is wrong to think carbon capture and storage will solve the climate crisis

    Ha, I'll be sure to mention you next time I see him!  Apologies, though, I assumed you had access to the journals - happy to forward you a copy if you're interested.

    As with anything, the degree of actual risk involved depends on the measures put in place to mitigate that risk.  Perceived risk is about how that actual risk is communicated.  The public (in the UK anyway) are against fracking because the perceived risk is high, primarily because of the stories coming out of the USA of contaminated drinking water.  In this instance, because of light regulations in the US, fracking *has* been a high risk activity.  The industry effectively got up to full-steam before any environmental impact research was carried out, and that is only now beginning to catch up.  CCS would be different (one hopes!), since the research is ongoing before an industry establishes itself and will inform regulators and operators of the requirements to avoid and mitigate.

    Fracking also has a hard sell because it is a deliberate fracturing of the rock, whereas the last thing you want when you're storing CO2 is to do anything of the sort!  Fracking is therefore inherently risky at the start of a project, particuarly if the subsurface geology is not well characterised.  CCS projects, on the other hand, are designed to be 'safe' because any leakage goes against the aim of the project, and there would likely be stiff penalties for allowing CO2 to escape - the framework for this is already in place in the EU under the CCS Directive, I believe.  Therefore, confidence should be high that CO2 storage is a safe thing to do.  Pressure maintenance is, of course, an issue and actually forms part of the basis for my PhD.  Pressure can be relieved or maintained at a level that will/should not induce any/significant siesmicity (through water production, say) and once the injection wells are shut off then pressure will dissipate through time as CO2 dissolves into the water, mineralises, and migrates laterally in the subsurface.  Careful also about scale - hydrocarbon fields are only a fraction of the size of the formations intended for CO2 storage.

    However, as you say, the public equate fracking and CCS as the same thing.  Communicating that they are different, with different levels of risk is clearly a challenge.  In the UK, CO2 storage will be offshore, so less of an issue here but there is already opposition to it in parts of Europe unfortunately!

  2. Dikran Marsupial at 20:01 PM on 27 November 2013
    Global warming since 1997 more than twice as fast as previously estimated, new study shows

    SASM, note section 2.2 of that paper investigates ocean circulation, which is the main difference between the Arctic and Antarctic that I mentioned.  Even if the greenhouse effect has the same direct effect on both poles, you still need to consider the transport of heat around the globe.  If there was no transport of heat by ocean and atmospheric circulation there would be no need to make climate models (GCM stands for General Circulation Model). 

    As I also pointed out, CO2 is not the only forcing that affects global and regional temperatures, so to expect a simple relationship between CO2 and temperature (especially over short timescales less than 30 years or so) is unreasonable.

    The really big point that was missing from my answer to your question was of course ice-albedo feedback.  Any summer melting of sea ice in the Arctic exposes dark ocean water, which absorbs far more sunlight than the bright ice that is now gone, so any warming there tends to be amplified.

  3. Global warming since 1997 more than twice as fast as previously estimated, new study shows

    SASM - your paper is complimentary. It looks at why Antarctica is colder than the Arctic. You will find similar papers over in the "Antarctica is gaining ice", No 10 of popular myths. The paper I stumbled on  at looks at the  role of the ACC in why SSTs are different between hemispheres under the same forcings which I thought was closer to your question. 

  4. No, Greenland Wasn't Green

    "men will desire much the more to go there if the land has a good name"

    Yeah. Lets never forget he was a Property Developer

  5. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    Here's an interesting statistic.  Global warming is causing the Earth's surface to accumulate energy (heat) at 248 times the rate at which the total human population is consuming food energy.  Put another way, global warming is storing 4.14 minutes worth of the total human food energy consumption every second.  That is an impressive figure.  But does it scare you?  Probably not.  The reason is that human food consumption is a difuse energy.  Because it is scattered across all continents, and over seven billion people, it is not concentrated enough to do harm.  It has high entropy.

    In that respect, the energy accumulation due to global warming is more like food consumption, and less like atomic bombs (or hurricanes, or earthquakes).  Indeed, the energy accumulating from global warming has a much higher entropy than that found in food.  Atomic bombs have very low entropy.  As a result, the energy in atomic bombs are capable of doing a lot of work, by rearranging buildings, cars, bridges, and humans.  An equivalent amount of energy with very low entropy would not do the same damage.

    To illustrate this, consider that the kinetic energy of the first kilometer of the Earth's atmosphere is approximately 7.1*1022 Joules, or about 1 billion atomic bombs.  That is two atomic bombs per square kilometer of the Earth's surface.  That does not trouble us for the energy is diffuse and disorganized.  It has very low entropy.  Where the energy gathered into a pinpoint and then allowed to expand outwards in all directions, it would be as devestating as an atomic bomb.  But because it is diffuse it is no more dangerous than a summer breeze.

    That is the difference between low entropy and high entropy energy - and the energy accumulated at the surface of the Earth has very high entropy.  That is why the widget is scientifically misleading.  It compares very high entropy energy to very low entropy energy.  Without explanation, casual observers (the people at whom the widget are aimed) will assume the energy accumulated also has the properties of all its comparators, ie, the raw destructive power from the very low entropy.  However it does not.  A moments thought shows that it does not have the destructive force of a billion atomic bombs rained down on the Earth's surface per decade.  And people who have that thought will feel misled by the analogies used.

    Finally, although the energy accumulating at the Earth's surface is high entropy, never the less it is decreasing the Earth's overall entropy.  It is not harmless.  Very far from it.  But its harm will be played out over decades and is far less than suggested by the atomic bomb analogy.  

  6. One Planet Only Forever at 16:01 PM on 27 November 2013
    Carbon Emissions on Tragic Trajectory

    Replying to SkepticalinCanada @12,

    I am also a Canadian. Unfortunately, Canada is a collective, and has not had enough collective popular support for the 'giving up of opportunity to benefit from unsustainable and adamaging pursuits that can be gotten away with', to get leadership that leads all of the population toward development of a sustaianble better future for all.

    Individual action is important, but keeping 'those who do not care' from getting away with 'what they wish to be free to do', is what is required. The leadership of Canada has never meaningfuly forced the required change of attitude on that uncaring part of the Canadian population ... so 'Canada' does not care.

  7. Global warming since 1997 more than twice as fast as previously estimated, new study shows

    StealthAircraftSoftwareModeler: 

    The curent and operative SkS Comments Policy can be accessed by clicking on the "Updated Comments Policy" link found immediately above the Comment edit box and below the "Post a Comment" header.  

    You will be better able to interact with SkS authors and readers on this comment thread if you focus your comment on specific issue and do not engage in polemics. Having said that, dialoguing on comment threads  on SkS and other websites may not be the best way for you to learn about climate science. There are other options such as signing up for an oline course or reading a textbook on the subject. 

  8. StealthAircraftSoftwareModeler at 14:33 PM on 27 November 2013
    Global warming since 1997 more than twice as fast as previously estimated, new study shows

    Scaddenp @75. I took a quick look at the abstract (all I can read) and this looks interesting and seems to support what you and Dikran were saying. Thanks for digging it up for me. I’ve done some searching and found this: LINK. This proposes a different mechanism than the paper you found.

    Moderator Response:

    [RH] Hotlinked URL that was breaking page format.

  9. StealthAircraftSoftwareModeler at 14:10 PM on 27 November 2013
    Global warming since 1997 more than twice as fast as previously estimated, new study shows

    Opps. Cut and paste error. Delete the redundant second paragraph in 76.

  10. StealthAircraftSoftwareModeler at 14:08 PM on 27 November 2013
    Global warming since 1997 more than twice as fast as previously estimated, new study shows

    John Hartz @74: I am really trying hard to get this.  I’ve gone and read several different Comment Policies in SkS, one from John Cook back in Nov 10, 2009 and one that I found in the article about the Dunning-Kruger effect.  For the record, I don’t see a link to the Comment Policy from the main menu links and one must search for it.  Between reading these policies, and examining my posts, I think I may have figured out the secret decoder ring of what you call sloganeering. I’ll try harder in the future to avoid it.

    Moderator Response:

    [JH] Repeated text deleted per author's request.

  11. Global warming since 1997 more than twice as fast as previously estimated, new study shows

    On an other track completely, I found this paper ("Interhemispheric asymmetry in transient global warming: The role of Drake Passage") on why models end up with interhemispheric assymetry in warming. The writers note the attribution to land-ocean differences between the hemispheres and Arctic sea ice melt, but also point out the role of the Antarctica Circumpolar Current in isolating Antarctica by running the models with and without a landbridge across the Drake Passage.

  12. A Miss by Myles: Why Professor Allen is wrong to think carbon capture and storage will solve the climate crisis

    Kit, thanks for your comment and I would refer readers here to Kit's blog VitaminCCS (good name!) which appears to be a useful resource on CCS (and say hello to Stuart Haszeldine for me, the last time we met was in a pub in Glasgow some 33 years ago).

    Unfortunately, I can't comment on the paper you linked to because it is paywalled (at a cost of  $35), but from your description of it, I don't doubt that the Duke paper we cited may well have unresolved uncertainties over natural baselining. Many of the disputes about methane and other contamination of aquifers due to fracking have similar problems. I do think that many of the contamination reports in movies like "Gasland" are exaggerated. But not all of them are. For example, a recent paper by Jackson et al looks very convincing to me. 

    Even if the aquifer contamination hazards of fracking and CCS are shown to be low, public opinion is likely to take some convincing. The difficulty that gas production companies have had in starting exploration projects in France, England, Quebec and New Brunswick are bellwethers of what CCS projects can expect in the future. Let's not forget that the quantities of water that are injected in fracking operations, although large, are much smaller than the liquefied gas amounts in CO2 sequestration projects. The injections of frack fluid are also short term to fracture the reservoir, after that the focus is on withdrawing fluid from the subsurface layer, reducing pore pressures as the gas is produced. In contrast CCS projects will continue to inject huge quantities of fluid over time, raising or maintaining pore pressures.

    This will lead not only to a higher propensity to leak or flow into other geological layers, but also a larger tendency to trigger earthquakes, because pore pressures will be elevated for longer. It may well be the case that most CCS sites will not leak much CO2 back to the atmosphere, but actual and perceived risks of CCS projects will be greater, I think, than for fracking projects, especially at the massive scale that is required of CCS to make a dent on global GHG emissions.

  13. A Miss by Myles: Why Professor Allen is wrong to think carbon capture and storage will solve the climate crisis

    Andy, RE: Hazards, be careful of the conclusions of the Duke paper on potential environmental impacts of CO2 on shallow aquifers by Little and Jackson.  See comments made by Gilfillan and Haszeldine here: http://pubs.acs.org/doi/abs/10.1021/es104307h Specifically, they concluded that CO2 could elevate concentrations of metals above USEPA guidelines in the aquifers studied, failing to stress that natural concentrations in these aquifers already exceeded the USEPA values, and secondly that in several cases metal concentrations were lower aith reaction with CO2, but they chose not to highlight this.  Much research has been done in this area, and is ongoing, and most of it concludes that there is a overall lack of concern with regard to "contaminating" water supplies.

    In any event, while the risk of CO2 leaking is definitely there, it is very unlikely that leakage would actually occur in the vast majority of storage projects.  Four mechanisms are employed in a typical storage site (residual, stratigraphic, solution and mineral trapping) to ensure CO2 is permanently locked away.  Public opinion is strongly against CO2 storage where the risks are poorly communicated, and I think your section on "Hazards" could be improved to communicate that the risks are nothing like what you are implying.  Perhaps I have read it wrong, but given this is my area of specialty in CCS, if it doesn't read right to me, then Joe Public isn't likely to find comfort in it either!

  14. No, Greenland Wasn't Green

    The vikings saw a few green coastal areas, but obviously not the interior and its vast scope. The term greenland was wishful thinking, or ignorance, or a marketing ploy to attract people.

    What caused the medieval warm period of europe? Presumably it could happen again, and seems to have had a reasonably rapid onset. Imagine if this was overlaid over human induced warming. This could have unpredictable and unwanted consequences to say the least.

  15. No, Greenland Wasn't Green

    There is already extensive discussion of the Viking settlement of Greenland in comments here, and especially here, starting with the comments of Spoonieduck and leading on to extensive rebutals.  Sufise it to say that the evidence supports the claims that:

    1. At the time of Norse settlement, as now, Greenland was less green (verdant) than either Iceland or Norway, so the name "Greenland" had a substantial marketing element, as noted in the saga.
    2. Greenland in limited areas then, as now, could support a small scale pastural industry, with some growth of vegetables and grains in gardens.
    3. Despite this, the settlements could not survive without extensive fishing and sealing, some of the products of which were traded to Iceland and Norway for grain, grain products (beer) and wood.
    4. Evidence from Norse settlement does not support claims that Greenland was warmer in the MWP than in the current decade, although due to some Norse harbours being bound by ice until recently, it was warmer than in the mid twentieth century. 

    As a minor point, the blog above appears to have already replaced the former content at the first link in my post (as is intended), but the update information has not been updated.

  16. No, Greenland Wasn't Green

    The history of the Greenland settlements is described in some detail in chapters 7&8, pages 211-276 of Jared Diamond's book 'Collapse - How societies choose to fail or succeed' published 2005 by Penguin.

    Diamond states that:

    "According to the sagas and medieval histories, around the year 980 a hot-blooded Norwegian known as Eric the Red was charged with murder and forced to leave for Iceland, where he soon killed a few more people and was chased out to another part of Iceland. Having ended up, there too, in a quarrel and killed still more people, he was this time exiled entirely from Iceland for three years ...

    ... Eric ... spent the next three years exploring much of the Greenland coast, and discovered good pastureland inside the deep fiords. On his return to Iceland he lost yet another fight, impelling him to lead a fleet of 25 ships to settle the newly explored land that he shrewdly named Greenland."

  17. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    ...and all of earth's systems seem to be connected via rubber bands; each in synchronous tension...until, when a few very important rubber bands become stretched to their yield point!  Snap!  Letting the huge wound up flywheel spin out of control.

    Apologies for the non-scientific perspectives.

  18. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    meb58 @11 "huge metal disk" is itself a famous metaphor for climatic inertia; see the 1979 "Charney Report":

    "[T]he ocean, the great and ponderous flywheel of the global climate system, may be expected to slow the course of observable climatic change. A wait-and-see policy may mean waiting until it is too late." 

    http://www.skepticalscience.com/nrc-report-on-ocean-heat.html

  19. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    I am an avid reader here, though I rarely comment...I'm not a scientist per se.  But one of the comments above really caught my attention with regard to the 4 hiroshima bombs; that the scale of eath's systems can absorb this kind of heat - with consequences of course.  The eye openner here is analogoous to spinning a huge metal disk...it takes an awful lot of energy to get it going but once in motion watch out.  This makes me think that even the most current radical measures to reduce warming won't be enough to slow warming...?

  20. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    As I mentioned on another blog recently, there is another precedent for the Hiroshima as a unit of energy that appeared on our national broadcaster a month before the original discussion: YouTube

    At the 9:50 mark, the host says:

    With such a huge area alight, a massive amount of energy was released into the atmosphere.

    In fact, in the peak 10 minutes of flaming, more energy was released than the Hiroshima atomic bomb.

    The reason is because people have an idea of what an atomic bomb looks like. We’ve all seen footage of them on TV, and pictures of the devastation they caused. We have some idea of the awesome amount of energy involved. And equating ten minutes of that fire to one Hiroshima atomic bomb emphasises just how big that fire was.

    So Australia’s national broadcaster had already, without fuss, used the Hiroshima atomic bomb as a unit of energy to try to help people conceptualise something that is inherently hard to grasp.

    For some reason my comment on that blog post about this prior art was ignored. Instead now there are additional comments relating to this widget and stolen SkS forum messages. Go figure.

  21. No, Greenland Wasn't Green

    From the 13th century Saga of Eric the Red (Eiríks saga rauða):

    In the summer Eirik went to live in the land which he had discovered, and which he called Greenland, "Because," said he, "men will desire much the more to go there if the land has a good name."

  22. Will extreme weather like super typhoon Haiyan become the new norm?

    "(The possible exception is disasters in the US, which seem never to be the fault of the victim.)"

    Just sayin', but there was an awful lot of blaming (or at least stigmatizing) the victims around Katrina.  And of course the 'God's fury' loons came out of the woodwork for Sandy as well, New York being in their eyes a Sodom on the Hudson.

    But (slightly closer to the topic at hand) I wonder about even the presumption that warnings lag greatly in all developing nations.  For example, the Christian Science Monitor reported that:

    www.csmonitor.com/World/Latest-News-Wires/2013/1113/Typhoon-Haiyan-Was-the-government-prepared

    Moderator Response:

    [JH] Unnessecary white space deleted.

  23. Help make our coverage bias paper free and open-access

    I've just asked the publisher for an update on the open access process. Hopefully I'll have more information tomorrow.

  24. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    @Dana1981 Thanks for the link to the original discussion. I missed that one. 

  25. Most of the last 10,000 years were warmer

    As noted above, I have overinterpreted the data available to me.  This is always a risk when interpreting scientific data as a non-expert.  In particular, not being expert I have not always read the range of scientific papers on a subject to put the particular papers on which I rely into context.  In this case I accepted too readilly the data from Langen and Vinthner, (2009), or more properly, their webpage on that paper.  Prompted by Foster/Wright above, I have since looked at a greater range of the literature and found a significantly more southerly source of Greenland precipitation in most papers (again without claiming an exhaustive search, so I may be missing something.  There are three key papers in this reassessment.

    1)  Johnsen et al (1998) find that most of Greenland precipitation, particularly on the west coast comes from "the subtropical part of the North Atlantic Ocean", with the best modelled results with an assumed source close to weather ship E (Echo), ie, just north of the Mid Latitude High:

    (Source)

    2)  Of particular interest in this discussion is Werner et al (2001), which examines source water for precipitation in both Greenland and Antarctica.  The find the only overlapping source for Summit at Greenland, and Vostok in Antartica is the tropical Indopacific, which provides just 10% of Greenland's precipitation, but 44% of Vostoks. Polar Seas provide 15% of Greenlands moiture, and the North Altantic 28%.  In all, 72% comes from the extratropical NH, and the remainder from the tropics, with none from the SH.

     

    3)  Also of interest is Sodemann et al (2008a), which discusses the sources of winter precipitation in Greenland.  In particular, the examine the effect of the North Atlantic Oscillation (NAO) on the sources:

       

    Again, the dominance of the North Atlantic as a source is evident; but so to is the large shift in source with a shift from postive to negative NAO.

    Overall, a clear picture that most precipitation from Greenland comes from the extratropical North Atlantic and Polar seas.  There is almost no moisture from the SH, and none from the SH extra-tropics.  There is an almost complete divergence between sources for Greenland and Antarctic ice, showing that neither can be considered a global proxy.  Further, Greenland ice shows a significant shift  in source based on dominant weather states (NAO) making it even less suitable as a global proxy.

    So, while my over interpretation has lead to a clear error in relationshipt to the dominant source of Greenland precipitation by placing it to far north, it does not effect the conclusion that Greenland ice cores are a regional, not a hemispheric or global proxy.  Curiously, the 44% contribution from tropical waters to the Vostok precipitation makes it, though clearly not a global proxy, a significantly better approximation than Greenland ice cores. 

  26. Global warming since 1997 more than twice as fast as previously estimated, new study shows

    StealthAircraftSoftwareModeler: Your three most recent posts have been deleted for violating the Comments Policy prohibition against sloganeering. Your proposensity to pratter on about anything and everything is indeed tiresome to Moderators and readers alike.

    Please read the SkS Comments Policy and adhere to it. If you do not, you will forfeit your privalege to post comments on this site. 

  27. Global warming since 1997 more than twice as fast as previously estimated, new study shows

    Further PS on SST change. What period on time are you looking at? Decadal level cycles like PDO and AMO affect SSTs. If you are only looking at <20 years, then that data doesnt tell you much about climate change.

  28. Global warming since 1997 more than twice as fast as previously estimated, new study shows

    PS. My evidence of ideological bias. In an interview with Watts on PBS.

    "SPENCER MICHELS: What’s the thing that bothers you the most about people who say there’s lots of global warming?

    ANTHONY WATTS: They want to change policy. They want to apply taxes and these kinds of things may not be the actual solution for making a change to our society."


    To me that sounds pretty much like the wonderful "skeptic" logic of "The only solution I can see to AGW involves things contrary to my political ideology, therefore AGW must be wrong". A better approach would be think up a solution that it is compatiable with your ideology.

  29. Global warming since 1997 more than twice as fast as previously estimated, new study shows

    You are only considering SST. How about looking at basin wide OHC? Looking at THC, you have northward movement of warm water into arctic, where it indeed cools, and sinks.

    Have you found things on this site by the way that arent backed by peer-reviewed published science (something you certainly cant say about Watts)? Do you think authors here delibrately mischaracterize science to support an idealogical position? It is good to be skeptical about science but there is a big difference between skepticism and delibrately pushing misinformation.

  30. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    Nice idea on ocean warming. I have another comment on communicating the science to the average person. Firstly I think the mainstream climate science community has done a fine job with the IPCC reports, and on sites like this.

    However there are problems as well. The issue is that the public mostly gets its information from the popular media and the sceptics tend to manipulate that and dominate it well. I have rarely heard the IPCC or leading climate scientists full force in the popular media pushing their case and refuting the sceptics.

    The few occassions I have heard the climate scientists in the press or on television, they over complicate things. I know scientists want to do science, but communication is essential people. Dont leave it to journalists or Al Gore he has too much political baggage. The public will only respect climate scientists or the IPCC.

  31. Most of the last 10,000 years were warmer

    re: steve foster @38-40, further research has shown that I have over interpreted the global circulation diagram and the data from one study shown above. It does not, however, support "Foster's" claims. I will discuss this in detail in a follow on post, but first go point by point through "Foster's"' claims:

    1) The troposphere includes the entire atmosphere from the base of the lowest blade of grass to (approximately) 150 hpa.  As such, it certainly includes winds over the ocean surface, and over Greenland, and hence it is tropospheric winds that account for the snowfall in Greenland.

    2)  Water vapour is carried far higher into the atmopshere in the tropics than anywhere else, but not in any significant amount into the stratosphere.  That is because the troposphere reaches to a far higher altitude in the tropics than elsewhere on the planet.  Because water vapour precipitates out with the cold, the stratosphere in fact has very little water vapour compared to the troposphere:

    (Source)

    3) You are missing the point.  The dry band at the northern edge of the NH Hadley zone results means nearly all water vapour from the tropics has been precipitated out.  Only a portion of it then travels further north, with most returnd to the tropics by the trade winds.  Of that which travels north, much of it will be precipitated out, with some of that being replaced by newly evaporated water vapour from mid-latitude oceans.  This is particularly the case as it travels along the surface.

    4)  Actually, Antarctica (168 mm year continental average) does recieve less precipitation than the Arctic (<500 mm per year average), with the highest most central regions of Antarctica receiving 50 mm per year compared to <100 to 200 mm per year for central Greenland (described as the driest part of the Arctic).

    5) The Arctic ocean varies quite significantly in winter temperatures, and away from the ice edge varies also in summer temperatures.

    6) Foster completely ignores the second figure in my preceding graph which shows the large difference in circulation between Holocene and glacial conditions, something I specifically commented on.

    7) As Phillipe Chantreau @40 points out, your maths on distances is just wrong.  More crucially, the stratosphere has very little moisture compared to the troposphere as can be seen by comparing the figure above to the zonally averaged specific humidity:

    (Source)

    Comparison shows a specific humidity of at least 1 g/Kg, ie, 1000 ppm by mass, through out the surface troposphere.  For comparison, stratospheric values are around 4 ppm by volume.  As H2O is a light molecule, that drops to closer to 2 ppm by mass.  Therefore the stratosphere is several orders of magnitude too dry to be the major source of precipitation at any location in the troposphere.  It is also far too dry to be a channel through which tropical (still less SH) moisture is tranferred to the poles.

  32. 2013 SkS Weekly Digest #47

    Neven is now covering the seabed methane article on his Arctic Sea Ice blog: http://neven1.typepad.com/blog/2013/11/and-the-wind-cries-methane.html#more

  33. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    Wonder if it would be a good idea to have it configurable so that the default comparison can be changed by setting a parameter in the embedding code?

  34. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    What about 25 hair dryers (1500 watts each) for every human on Earth running 24/7?

    Or 2 or 3 electric cars?

  35. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    I would encourage people who have concerns about the Hiroshima bomb unit of energy to read John Cook's post from a few months ago, 4 Hiroshima bombs worth of heat per second.  This wasn't a spur of the moment decision, we put a great deal of thought into it.

    And if you're uncomfortable with that unit, the widget offers others like Hurrican Sandys, lightning bolts, etc.

  36. Carbon Emissions on Tragic Trajectory

    wili@13,

    Here's an interesting quote from that article:

    About 17 teragrams of methane [...] escapes each year from [...] East Siberian Arctic Shelf, said Natalia Shakova, [...]; the world emits about 500 million tons (teragrams) of methane every year from manmade and natural sources. The new measurement more than doubles the team's earlier estimate of Siberian methane release, published in 2010 in the journal Science.

    (my emphasis)

    If their estimates are accurate, that would partially explain the increase in CH4 concentration from late 2000s:

    Methane.jpg

    The concentration increased by ~.050ppm, from 1.740ppm, which is %3, while contribution from Arctic Shelf's emissions jumped from ~8/500 (1.6%) to ~17/500 (3.5%). That difference (up to 2%) does not quite make up the %3 difference in concentrations but the most of it. The rest must be coming from other sources, perhaps increased emissions from hydraulic fracking. Keep in mind that these are just rough envelope calculation by myself; proper calculations may give different proportion.

  37. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    Hi, I like the idea of using metaphors in order to get the message to the public....but. To use the image of Hiroshima bombs to instruct people about global warming seems to me a little over the edge. Scientifically the comparison is like 5 pears equals 5 appels. And I do not really think that the public gets the message except that naming Hiroshima is like naming the Holocaust. It is intended to shock people. I think people should be shocked about Global Warming, but for the right reason.

  38. 2013 SkS Weekly Digest #47

    Thanks for the mention. :)

    Moderator Response:

    [JH] You're welcome and thank you for all that you do.

  39. Most of the last 10,000 years were warmer

    DB...  Why am I not surprised?

  40. Will extreme weather like super typhoon Haiyan become the new norm?

    wpsokeland@34

    "The average trmperature of our globe is varying over the past 30 years with swings of 0.1 to 0.2 degrees centigrade -- up and down. The general overall trend is upward. Since the solar constant, your only energy source ts constant and, if greenhouse gases were continually increasing via human input, the average temperature of our globe would be continually increasing. There would be no temperature swings as seen in the data. Any PhD in heat transfer would know that a different energy source is active in the real temperature variation." (my emphasis)

    I agree that any Ph.D. in heat transfer understands conservation of energy, and thus, to the extent that the thermal energy that is added to a system isn't converted into something else like chemical potential energy, latent heat of phase change, mechanical work, or mechanical potential energy, the average temperature of the system (as long as "average temperature" is calculated by properly weighting temperature data with heat capacity of the material at the recorded temperature, to accord with conservation of energy) is generally physically forced to rise when you add thermal energy to it.  I don't think you have to be a specialist in heat transfer or have a Ph.D. or even a B.S. in anything to understand conservation of energy.  Conservation of energy is an intuitive concept that people are generally taught in required science courses in high school if not before.    

    That said, I suspect you are misapplying the principle of conservation of energy to the global climate.  What do you mean by "average temperature of the globe?"  I assume you probably mean average surface air temperature over land?  If so, that represents a very tiny component of the thermal energy of the climate system, about 90% of which is found in the oceans.  Given the cycles of heat flow back and forth between the oceans and the land and atmosphere, it is unsurprising and consistent with AGW theory that there are fluctuations in land surface air temperature rather than a constant rise.  My understanding is that, when you account for warming of the oceans, the total thermal energy of the climate system has been consistently increasing over the past 30 years, as would be expected given the thermal disequilibrium caused primarily by spiking CO2 levels primarily due to human activities.  

  41. Carbon Emissions on Tragic Trajectory

    LiveScience has a good article on the methane study, too. LINK

    RealClimate and neven's Arctic Sea Ice blog are both planning lead posts on this story soon. How about SkS?? '-)

    Moderator Response:

    [RH] You can actually hotlink your own URL's if you look at the second tab above the comments box labeled "insert." Just highilght the text you want to link and the paste the URL into the box that pops up. It's easy and will save the moderators some work. Thx!

  42. Global Warming Paws Fails to Materialise: Earth Still Warming and Global Sea Level Rising Like Gangbusters

    I sent a summary of this paper to a friend who is both a scientist and somewhat skeptical of the AGW consensus. She sent me a response to the article (and a few others that address the gap in arctic coverage) by Judith Curry. I read Judith's response and I had a very hard time following her critique. I have seen some responses to what Judith Curry has written on other issues in the comments on Skeptical Science but I am not aware of anything on this particular issue. I would like to provide my friend with a response to Judith Curry's critique that focuses on the science. Any suggestions?

  43. Dikran Marsupial at 02:19 AM on 26 November 2013
    Global warming since 1997 more than twice as fast as previously estimated, new study shows

    Thanks Michael, glad to hear my intuition wasn't too far out!  Hopefully this fully addresses SASM's question.

  44. Global warming since 1997 more than twice as fast as previously estimated, new study shows

    Dikran,

    Freezing of sea ice releases a lot of heat into the atmosphere.  This accounts for much of the increase in temperature in the Arctic in fall.  Then the ice insulates the ocean from the coldest part of the winter.  In the summer, that heat is absorbed again from the sun to melt the ice.

    The melting and refreezing of sea ice does not contribute to the net heat budget of Earth since it is returned later.  Melting ice caps uses some heat, but it is a small fraction of what the Earth absorbs from AGW.

  45. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    Dang, deleted some text in that last paragraph.  The gist is apparent, I hope.

  46. 4 Hiroshima bombs per second: a widget to raise awareness about global warming

    Heh, synchonicity...

    A while back I was talking with one of my colleagues in the staff tea room and, after a bit of back-of-the-journal-envelope arithmetic, we worked out that at the rate that the human population is currently growing, if one started from around the time that the Keeling curve data began to be collected the rate of Hiroshima energy accumulation would follow pretty closely the human population clock as it ticks over today.

    Except that the accumulation of energy is about 4.6 bombs/second using the value for Little Boy was actually a little greater than the rate of turning over of the human population clock, so the HPC would run too slow...

  47. Dikran Marsupial at 18:41 PM on 25 November 2013
    Global warming since 1997 more than twice as fast as previously estimated, new study shows

    SASM If you want to avoid the impression of trolling, when someone answers your question, explicitly state those parts of the answer that you accept, and explain why you reject those parts of the answer that you do not accept.  Do not just raise another objection without dealing correctly with the answer you have already been given.  A common tactic of trolls is not to give a hostage to fortune by explicitly agreeing to anything as it means that they cannot then go back to that topic later and say the opposite.  Also if someone asks you a direct question, give a direct answer.

    Now as to the assymetry.  The Arctic is an ocean and it has currents floating into and out of it all the time.  As the Arctic ocean is colder than the Atlantic or Pacific, that suggests that these ocean currents are on balance transporting heat into the Arctic, causing it to be warmer than would otherwise be the case.  This doesn't happen for the Antarctic, becase it is a land mass, so the ocean currents can't bring heat to the pole (note the Anarctic peninula is warming).  Secondly if sea water gets much colder than 0C it freezes, rather than getting colder.  This means that the ocean under the ice is much warmer than the air above it in the Arctic.  There is no similar phenomenon that stops the rock under the ice in Antarctica from getting colder until there is an equilibrium with the air temperature above the ice.  I am not a physicist, but my intuition suggests that the formation of ice is slightly exothermic (i.e. gives out heat) as otherwise you wouldn't need heat to melt it.  That explains why the oceans don't get much colder than a few degrees below zero C (depending on salinity).  I suspect someone here who is a physicist can explain the details.

    P.S. I was going more for an English civil war look ;o})>

  48. 2013 SkS Weekly Digest #47

    re: Toon of the Week

    Brilliantly summing up COP19 and the undergoing political process. Just plain and simple brilliant.

    And not for the first time.

  49. Super Typhoon Haiyan: Realities of a Warmed World and Need for Immediate Climate Action

    YubeDude,

    Side note on bamboo for construction/scaffolding:

    I first came across it being extensively used in Hong Kong. My first thought was that it was a third world thing (not really knowing Hong Kong's financial status at 22 year of age). But then someone told me that it was a great material, as it was cheap, lightweight, easily and quickly grown, strong and flexible. Scaffolding can be more extensive and higher thanks to the weight/strength ratio.

    I also learned that it is a better scaffolding material for high winds, taking the force of wind better than metal, owing to the flex, and that if it falls, the lighter weight does less damage.

    So though it looks like a compromise developing countries have to make, it turns out that it may well be a better choice of material, especially for high wind events.

    Rebuilding costs to developing countries is a subtler issue than at first glance. If infrastructure is cheaply made and restored, then rebuilding could be less onerous, other factors depending, than for wealthier countries with expensive infrastructure. But a fairly safe generalization is that structures in the developing world (bamboo scaffolding aside), do not withstand high winds as well as wealthier countries. Immediate impact for third world communities is more devastating. And, according to the IPCC, most areas of the world more vulnerable to the risks of climate change are where developing countries are.

  50. 2013 SkS Weekly News Roundup #47B

    Trevor S @4, voters have only limited influence over the policy outcomes of elections, despite propaganda to the contrary.  The first, and most fundamental reason for this is that voters do not get to vote for policies individually.  When you go to an election, you get to vote for a candidate for your local seat and (depending on jurisdiction) perhaps also an upper house member and/or chief executive.  The candidates you are voting for will have a large number of policies, either personally, or as dictated by the policies of the party for which they stand.  Consequently, when you vote for a particular member, you do not, because you cannot vote for any one policy.  Rather you vote for a bundle of policies, some of which you may disagree with.  Further, you do not just vote for that bundle of policies, but also for the member (and their party), and hence as part of the bundle for which you vote is an estimate of the integrity, intelligence and vigour of the candidate and the administrative competence of the party.

    If this were not enough, candidates will often hide some of their policies, of simply change their policy after election.  On top of that, the voter is more or less lied to continuously by the supposedly free press, much of which considers its role in a democracy to by similar to that of Pravda in the USSR.  Even diligent citizens, therefore, must be to some extent ill informed.

    Consequently, the claim that the policy outcome of a newly elected government is "what the voters want" is simplistic, and in fact must be false in any democracy in which policies are not approved line by line by the electorate.  At best, the policy outcomes are what the voters can live with, given the range of policy and administrative alternatives.

    This is not to exonerate voters for the slow and ineffectual response to climate change.  However, the politicians and journalists who should have as their first duty the facilitating of their full accountability to the electorate, but who have instead resorted to irrational policies, faux policy debates, personality politics, and outright lies (in the case of politicians); and to false balance (at best) and in many cases outright anti AGW mitigation propaganda (in the case of journalists) bear far heavier blame.  They are betraying democracy, and with it the citizens of their nations.  Unfortunately, in the face of global warming, they are betraying future generations at the same time. 

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