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Comments 38701 to 38750:

  1. A methane mystery: Scientists probe unanswered questions about methane and climate change

    In the figure by Andy@2, the biggest surge of emmisions happened at N mid-lattitude around 2002-2003. That was immediately followed by the biggest drop in the following year at the same location (is it really the same 'locality' in the raw data or just happens to be in the same band but somewhere else, e.g. NAmer vs. Europe/Asia?). These are the two biggest anomalies on this figure. Has anyone looked at explaining this? Do we have a 'smoking gun' here (but do not understand the processes involved yet) or is it just random noise from naturaql variabilities?

  2. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    Last year, Tamino estimated the influence of ENSO with a 2-box model, NASA forcings and SOI data for ENSO.

    Could someone explain me what's the difference with this tremendous new study ?

  3. A methane mystery: Scientists probe unanswered questions about methane and climate change

    thanks, witsend @10 for pointing out that paper. However, the study was about live, standing trees, not dead/decaying trees. Its sample size was very small, the variability (range) near 100% in most cases, and its extrapolation (from the mean) rather bold. If real, there is no reason to believe the source (~20 Tg/yr, thus relatively small) would not have existed before 2007/08, thus cannot explain the current rise.

  4. Discussing global warming: why does this have to be so hard?

    In the '2014 SkS Weekly News Roundup #6' there was an article 'How to convince your friends to believe in climate change' that seemed fairly helpful.  Shortly, avoid trotting out Scientific facts or Scientific consensus.  Come from your heart, state that the issue is important to you.  Then offer 4 reasons why you 'came around': 1)taking action is like taking insurance, 2)taking action will involve nuclear power, 3)since illness hits people where they live, talk about how tropical illnesses are expected to spread if we do nothing, 4)mention that the US Department of Defense considers AGW to be a top threat.  If I get the psychology right, you aren't talking to people who care about Nature, and have probably already pegged you for a 'Tree Hugger'.  These people are prudent and buy insurance policies to cover most things, they like nuclear power because they know it irritates the 'greenies', like most people they feel illness in their bones, and they are apt to salute whenever you mention the Military.  Good Luck!

  5. Discussing global warming: why does this have to be so hard?

    What Russ R is pointing to for "unintended consequences" to my mind is actually the certainity of pursuing policies favoured by business lobby groups which nearly always turn out badly - namely using subsidies. That these will have unintended consequences is a near certainity not an uncertainity. I accept the need for government subsidies on health and education but in every other arena, they tend to be a disaster. "Dry" governments of both left and right here (NZ) in the 90s ended subsidies right across the economy - a good move. 73% renewable generation and no subsidy in sight. First step is kill subsidies on fossil fuel, second step is ban new generation using FF and let the market decide the next best source. The obvious foreseeable consequence is that you will pay more your energy. However, you are going to pay more future energy one way or the other - if not directly, then through your insurance bill if not worse.

  6. Discussing global warming: why does this have to be so hard?

    CBD @14...  But I think all that is a function of how many conservatives are processing the problem. Scientists say we have this looming issue that can have extremely severe consequences in 75-100 years. In the minds of many people that just doesn't compute at all. When you say, "75-100 years" you might as well be telling them the problem is on another planet. And then we're saying we need to adjust markets and taxes to compensate for this problem that exists on another planet.

  7. Discussing global warming: why does this have to be so hard?

    I tend to agree with Russ R.  The cost of the baby steps we have taken to reduce emissions are going to be insignificant compared with what we need to do to stay at 400.  The costs are up front.  The benefits and costs avoided are a number of decades in the future. 

    HOWEVER, when I went to look for a specific example, it went the other way.  The five year ownershop costs for a Nissan Leaf, according to Edmunds, are about $4000 less than the five year costs of a Toyota Corolla.  And that doesn't include the $7,500 tax subsidy that the leaf gets. For someone who just needs a commuter car, the Leaf is a good deal. 

  8. Discussing global warming: why does this have to be so hard?

    This just doesn't match my experience. So far as I have seen, nearly everyone who contests AGW does so on the basis of disbelieving one or more of the three 'known and not controversial' items listed in the OP.

    Yes, it would be wonderful to have a logical discussion about risk and uncertainty and the best course of action in the face of proven realities... but that just isn't anything remotely similar to what I see. I'd estimate maybe one 'skeptic' in a thousand accepts the basic realities of global warming and is only questioning the details. Frequently, even those who actively say that they accept the science will 'slip' and repeat the most demented illogical arguments imaginable. Thus, I don't believe this is a 'rational debate' at all. Getting to that stage would require a significant change in beliefs by the vast majority of climate 'skeptics'.

    To take the Inhofe example, no it doesn't seem likely that he has a 'villain lair' where he plots new ways to destroy the planet, but he also certainly isn't anything like the 'rational skeptic' portrayed in this post. No, he is out there saying that human greenhouse gas emissions cannot cause warming. That volcanoes caused CO2 levels to rise. That AGW is all a big hoax. Et cetera. And he isn't alone. That is standard fare from Fox News, Limbaugh, virtually every GOP politician, and the rest of the 'conservative' (an even less accurate term than 'skeptic') faction in the U.S. Maybe it is different in other countries, but I for one would be unspeakably relieved to see anything like the level of sanity this post suggests exists.

  9. Discussing global warming: why does this have to be so hard?

    Russ R.@11: google "ray kurzweil solar will power the world in 16 years".  It's not my idea. It's an extrapolation of a 20 year trend.  I certainly hope you're right about SLR, but nature reveals itself in exponential functions all the time, and I can think of no physical reason why it wouldn't apply with SLR as well.  The main thing, however, is the uncertainty: we're messing with a form of matter whose flow behavior gifted the English language the word 'Avalanche'.  That's like taunting a Shark.

  10. Discussing global warming: why does this have to be so hard?

    Composer99@10: To tack on to your point, and add to my own (above), here, in red, is the shape of sea level rise from ice sheet melting, in the last 10 years:

    http://www.skepticalscience.com/pics/SLRIcesheetcontributions-VanDenBroeke2011.jpg

    It's an exponential curve, as would be expected in a situation like this, and I found that a reasonable approximation to it is: Cum SLR = exp((year-2000)/4.1).  Assuming this trend continues out going forward, then SLR hits 5 feet by 2030, and 57 feet by 2040!! I can't believe it'll happen that fast, but I also can't believe it'll trend linear either.  We are in uncharted waters: a tipping point has been passed, in 2000, and nobody noticed.  Ice sheets are melting exponentially, as one would expect, and the nonlinear exponential function is no help when it comes to prediction accuracy.

  11. Discussing global warming: why does this have to be so hard?

    ubrew12:

    "Suppose that rate doubles every ten years? Then by 2100, 17 feet will have been added,..."

    "Only 8 more doublings and Solar PV could power the World."  

    Your technique of extrapolating exponential growth into the future... you might want to rethink it.  It doesn't work so well in the real world.

  12. Discussing global warming: why does this have to be so hard?

    Russ R:

    In my view, Dr Abraham is overstating the uncertainties regarding global warming - or rather, that he has not clarified enough the distinction between the uncertainty regarding ultimate outcomes and uncertainty regarding timeframes and severity.

    For example, analysis of paleoclimate data suggests that, if CO2e were to stop dead at 400 ppm, we would still be in for substantial sea level rise due to the melting of the large ice sheets in Greenland and Antarctica (e.g. see here for an estimate of sea level, relative to the present, in the last interglacial period). If that emissions continue unabated, we can be extremely confident that given time, all the ice would melt away eventually.

    The ultimate outcome of unabated greenhouse gas emissions - massive sea level rise following the melt-off of the continental ice sheets - follows of necessity from the assumption of unabated emissions and what is presently known regarding cryosphere response to global warming. There is, effectively, no uncertainty regarding the ultimate outcome: if we warm the planet enough we could end the current ice-house state of the Earth and return it to an ice-free, hot-house state. This would entail a sea level rise of some tens of metres.

    What is uncertain is how long it will take to get there. A higher climate sensitivity and more sensitive ice sheet response, for example, would suggest such sea level rise would occur very rapidly, in geological terms at least, and vice-versa for lower sensitivity and less sensitive response.

    As the ultimate outcome of unabated warming with respect to sea level rise is not in doubt, we must sooner or later look to decarbonisation and, if technology permits, carbon sequestration in order to avoid it (on the assumption that multi-metre sea level rise is undesirable).

    I could go on about other consequences of global warming - impacts on (agricultural) plant growth and distribution, heat stress on mammals, and so on. The ultimate consequences of unabated warming are, in my view, very cut and dried; the uncertainty lies in how quickly they will arrive (and/or how they will be distributed spatially, in the case of, say, changing weather patterns).

    What is more, the ultimate outcomes of warming are not avoidable just by virtue of climate sensitivity being, say, on the low end of IPCC estimates. All that means it that it takes longer to get there, assuming unabated warming.

    TL,DR: Assuming we want to avoid the ultimate outcomes of global warming, we have to abate it. And, as many people have pointed out in many articles and comment threads here and elsewhere, while there may be reasonable points of disagreement on how quickly and extensively to ramp up decarbonisation and sequestration, uncertainty is not our friend.

    ----------

    As some final notes, with respect to the Globe & Mail article, I find the following paragraph very telling:

    It is also the latest sign of turbulence in the green-energy industry after the global recession reduced the need for power and an uncertain economy made less costly conventional electricity more attractive than pricey renewables.

    Leaving aside the fact that in Ontario about half of power generation is from nuclear power, the remaining proportion of "conventional" (that is, fossil fuel) electricity is only "less costly" than renewables because of (a) enormous direct and indirect subsidies paid out by various levels of government (in effect, we citizens pay fossil fuel power generators for the privilege of having lower numbers on our bills and at the fuel pumps), and (b) the rather large externalized costs of fossil fuel combustion (namely, global warming and its attendant consequences), which are not currently well-reflected in the prices we pay for, say, electricity from fossil fuels. (This latter point is the basis for arguing for carbon taxes, fee-and-dividend systems, and the like.) Their lower apparent cost compared to renewables is, in effect, an illusion.

    Further, the Globe & Mail article suggests that the growth of renewable energy in Ontario is not falling victim to some perverse consequence of pursuing renewable energy per se, but rather to such things as retrenchment during economic stagnation and what I assume would be a normal driving down of prices due to over-supply ("After a decade of rapid expansion, during which Ontario badly wanted to increase the power supply as it shut down coal plants to cut greenhouse-gas emissions, the recession drove down demand and the province wound up with an electricity surplus"), austerity measures and/or perception-management by the government ("The still-shaky Ontario economy has also made it politically harder to justify the cost of subsidizing green power both to cash-strapped households and industrial enterprises for whom power is a major business expense"), and competition ("The rise of low-cost solar panel manufacturers in China has put further pressure on Western-based companies").

  13. Discussing global warming: why does this have to be so hard?

    What I often wonder is whether much of the conflict on this issue revolves around how people process risk differently. And that may play into the whole liberal/conservative aspect of it as well.

    My sense is there are people who respond to immediate risk and those who respond to long term risk. I think you see it playing out right now in the US in terms of the national debt. Conservatives view the debt as this problem that must be addressed immediately. Liberals tend to lean toward saying, the debt is important but is something that can addressed over a longer period. It's short term vs long term risk response.

    The same thing plays out relative to climate where conservatives tend to focus on economic risks related to addressing climate change now, whereas liberals tend to look at the longer term risks of not addressing climate change.

    The nit for all of this is that, honestly, I believe addressing the long term issue can have net economic benefits now. 

  14. Discussing global warming: why does this have to be so hard?

    Russ...  I would also add, unintended consequences going to happen one way or another, regardless. Renewables are on an unrelenting march toward cheaper and cheaper energy. Any problems that are going to rise from this are going to rise whether we manage that process or choose to just let it happen.

    What would be a shame would be if we did have all the technologies and abilities to address climate change but acted too slow to make a difference. That's a very real possibility as things are going right now.

  15. A methane mystery: Scientists probe unanswered questions about methane and climate change

    Since methane is an energy source for a range of bacteria and bacteria can multiply at prodigious rates if the conditions are right, perhaps we are looking for a sink involving methane using bacteria to explain the missing methane. Also the comment (5) that the rate of a chemical reaction is very much dependent on the concentration of the reactants is very much to the point.

    Incidentally, methane is a lot more powerful than 50times Carbon dioxide.  A recent figure given in the NSIDC was X86.  Reverse engineering the figures suggests as much as X140

    http://mtkass.blogspot.co.nz/2013/03/the-real-strength-of-methane.html

  16. A methane mystery: Scientists probe unanswered questions about methane and climate change

    Perhaps the methane increase is due to dying trees.  Interesting that the jump began in around 2008, which is the year I first noticed that they are all dying.  From this post:  http://witsendnj.blogspot.com/2012/10/spill-scarlet-rain.html

    New information also comes from the Yale School of Forestry, where researchers have discovered high levels of methane emissions from trees that are dying from fungal infection, which they claim is a worldwide phenomena, and yet they cannot (in fact, don't even try to) explain WHY trees that are only at the beginning of maturity (80 to 100 years old) are dying prematurely all over the earth. I suspect they do not appreciate the implications of their own discovery beyond the acceleration of climate change. From SummitCountyVoice:

    Sixty trees sampled at Yale Myers Forest in northeastern Connecticut contained concentrations of methane that were as high as 80,000 times ambient levels. Normal air concentrations are less than 2 parts per million, but the Yale researchers found average levels of 15,000 parts per million inside trees.

    “These are flammable concentrations,” said Kristofer Covey, the study’s lead author and a Ph.D. candidate at Yale. “Because the conditions thought to be driving this process are common throughout the world’s forests, we believe we have found a globally significant new source of this potent greenhouse gas.”

    “If we extrapolate these findings to forests globally, the methane produced in trees represents 10 percent of global emissions,” said Xuhui Lee, a co-author of the study and Sara Shallenberger Brown Professor of Meteorology at Yale. “We didn’t know this pathway existed.”

    more at the link above.

  17. Discussing global warming: why does this have to be so hard?

    Russ R@4

    Russ, I think this is called a hasty generalization. In the US, we've instituted mileage standards for autos and provided incentives for hybrids to promote development of that technology. Amazingly enough, the economy hasn't collapsed as a consequence of that action, and the desired result has occurred-- we're moving in the right direction on emissions.

    Those who are concerned about negative consequences need to be able to rationally project them, not just point out that 'stuff happens'; we already knew that. It's about balancing uncertainties.

    For the US, I would give the following hypothetical. Let's, by subsidy and regulation, promote the installation of rooftop solar everywhere reasonable, requiring that such installations incorporate a backup mode (capacity variable, but not needing the grid) for when the power goes out.

    OK, how confident would we have to be about any of the uncertainties listed by Abraham for that to be a reasonable idea, and how confident about a suggested downside to reject it? That's what an honest discussion would involve. But we never have those; we have rhetoric as usual.

     

     

  18. Discussing global warming: why does this have to be so hard?

    I guess its more like 33 ft by 2100 but you get the idea.

  19. Discussing global warming: why does this have to be so hard?

    "2. We don't know how fast it will happen."  Based on the last 40 million years of strong correlation, the sea level that corresponds with today's 400ppm of CO2 is 25 to 125 feet higher than today's sea level, or on average 75 feet higher.  Before 2000, Antarctica and Greenland contributed nothing to sea level rise.  Since 2000, the contribution of these two ice sheets has increased at an exponential rate (note: exponential function also useful for describing explosions).  As IPCC has related, five times more ice melted off these ice sheets in the last decade than in the decade before.  Since 2000, they have added 0.4inches (10mm) to sea level.  Suppose that rate doubles every ten years?  Then by 2100, 17 feet will have been added, so they'll 'only' have 58 more feet to go.  So, that is one estimate for 'how fast'.  I'm sure there are others.

    As for Russ R. above, do you know what else is growing exponentially?  Solar PV power.  Every two years the installed base doubles (a trend now 20 years old), and the price per panel drops by 40%.  Only 8 more doublings and Solar PV could power the World.  Google 'citibank energy darwinism' for more information.  Nick of time?  Hold on to your hats, it could be close.

  20. Warming oceans consistent with rising sea level & global energy imbalance

    To your point, CBD...:/

    http://xkcd.com/1321/

  21. Discussing global warming: why does this have to be so hard?

    vroomie,

    John Abraham's post listed 5 areas of uncertainty:

    1. How much climate change should be expected?
    2. How fast will it occur?
    3. How will it manifest?
    4. How much is natural vs. man-made?
    5. How will it affect economies and societies?

    He failed to mention a sixth:  the uncertainty surrounding the costs and impacts of the policies being prescribed to "fix" this problem of uncertain size, timing, effect, source, and human impact.

    In the two examples I provided (and many others) the actual, realized costs of policy action have greatly exceeded what was expected, as Spaniards, Ontarians and others are discovering to their dismay.

  22. 2013 was the second-hottest year on record without an El Niño

    Klapper...  Perhaps you actually missed that One Planet did address you with facts and support. You're merely finding a way to wave off One Planet's comments without addressing them.

    Clearly, one very important element of "facts" is the capacity to see them when they're presented. A consistent theme with you seems to be a willingness to ignore some facts and elevate other facts beyond their relative importance.

    "Reality" is the balance of all the data and facts, not just the one's you prefer. This is a theme eloquently presented by Tamino in a recent post.

  23. Discussing global warming: why does this have to be so hard?

    In my haste to argue about what John Abraham left out of his analysis, I neglected to commend him for presenting an otherwise very level-headed and even-handed perspective.  It's rather refreshing.

    Reasonable people can agree on facts, acknowledge uncertainties, and disagree about what should or shouldn't be done, without automatically resulting in "clenched fists and indigestion".

  24. Discussing global warming: why does this have to be so hard?

    Russ R., I find it *incredibly* difficult to believe your assertion: I've read many, *many* articles, journals, and academic papers that show it's qwuite the opposite. Many study these effects, and it iis disingenuous to suggest it is "being ignored."

     

    There may well be an instance, here and there, that shows this --the effects of climate policies-- is in its infancy, but to suggest no one is looking into this issue, is not believable,

  25. Discussing global warming: why does this have to be so hard?

    There is one other major area of uncertainty that is being ignored here...  

    6.  How will climate change policies (and their unintended consequences) impact economies and societies?

    You might consider, as an example, the recent experience in Spain:  http://www.nytimes.com/2013/10/09/business/energy-environment/renewable-energy-in-spain-is-taking-a-beating.html

    Or, as another example, Ontario:  http://www.theglobeandmail.com/news/politics/ontario-cuts-back-on-green-energy-deal/article12718627/

  26. A methane mystery: Scientists probe unanswered questions about methane and climate change

    tblakelee, that would fall under the "mining fossil fuels" catagery in the opening sentence.

  27. A methane mystery: Scientists probe unanswered questions about methane and climate change

    tblakeslee @7: The important words here are "can" or "may" as you used. Have a look at this and this post. Like with any other industrial process, there is a chance things go wrong, and therefore risk management, proper planning, and execution is needed. If BP and the other companies involved had adhered to that, the Deepwater Horizon may have never been in the news. Suffice it to say, reality is different.

  28. A methane mystery: Scientists probe unanswered questions about methane and climate change

    What about the extensive horizontal drilling and fracking to release natural gas from tight shale formations. It seems that a lot of methane may be released before it can be captured.

  29. A methane mystery: Scientists probe unanswered questions about methane and climate change

    @3&5

    Actually, the article did not discuss sinks much because oxidation of methane in the troposphere is very well understood. It constitutes the major sink of methane, minor sinks being soil (not ocean, which is a source) uptake by methanotrophs and oxidation in the stratosphere. The oxidation sink it maintained by OH radicals and there is no evidence that the abundance of that radical is changing. Hence, as we do know methane sinks better than its sources, the renewed tropospheric increase is indeed thought to be a proxy for changing source strength.

    The graph from the paper, presented at the AGU Fall Meeting in Dec. 2013 and posted by Andy @2, is a spatio-temporal extrapolation of the tropospheric methane growth rate calculated from gas samples obtained from the global sampling network. The network is comparatively sparse, thus the fine detail of the map should not be overinterpreted. It is, however, detailed enough to conclude that the largest growth rates since 2007 have occurred in the tropics and northen midlatitudes (2009, 2012). Not much more can be said than what is in the article. However, from what is known about the sources, particularly the largest source, natural wetlands, wet and warm years in regions like the Amazon, have significant effects on tropospheric methane, and so do years with large biomass burning emissions (e.g. Simpson et al., JGR 2006).

    If the tropics were to get not just warmer, but also wetter (that is the expectation), there is thus likely a positive feedback loop on warming via increasing wetland methane emissions. The same may be true for biomass burning if on average more burning will occur as a result of warming and drying in seasonally dry tropical and subtropical regions.

    The discrepancy between bottom-up and top-down budget estimates is actually nothing new. The inventories are often outdated, and rarely carefully checked against atmospheric data. Not too surprising because maintaining inventories is cheap compared to measurements. That does not mean the inventory is always bad, but it cautions against trusting it, especially when it is old and/or based on limited input data. The global inventory is not necessarily biased the same way as the US inventory, so while recent US data create a perception that emissions are generally underestimated, that does not automatically mean the same should be true for global emissions.

  30. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    @HK #49:

    My original post didn't mention the sun. It put forward a relatively simple concept: if the IPO can suppress warming, it possibly can enhance it too. Hence some part of the warming of the late 70's to 2000 might have been driven by the +phase of the IPO. Whether this cycle in the IPO is driven by indirect solar effects (I don't think it could be TSI), I don't know. Certainly some scientists like Nicola Scaffeta think it is somehow related to solar cycles, even though he does not specify a hypothesis of the mechanism.

    However, the cycle exists, whether we understand the mechanism or not. That is the real topic of this blog, and my point remains: could the +IPO have enhanced the warming between 1975 and 2000?

  31. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    Given that the deniers are pointing to two papers about the Walker circulation.
    See jsam and Terranova above.

    It would be useful if someone clarified the difference between what is researched/described in those papers as opposed to what is looked at Matthew England et al.

  32. Dikran Marsupial at 00:36 AM on 13 February 2014
    Models are unreliable

    knaugle "Most current climate models completely missed the current warming pause."

    This is actually completely unsurprising, however to see why this is, you need to understand how GCMs operate, which in trun will show what they can reasonably expect to be able to predict and what they can't.

    Imagine we had a quantum mirror which we could use to visit Earths in parallel universes.  Say we could choose only those where the climate forcings (e.g. solar, volcanic, aerosols, CO2 etc.) are exactly the same as they are on our Earth, but the initial conditions are slightly different (e.g. a butterfly flapped its wings on one, but decided not to bother in another).  In this case, the response to the forcings will be exactly the same on the parallel Earths, but each will have a different set of variations in climate due to sources of "internal variability" such as ENSO.

    Now you could have no better climate model than this, even in theory, as the parallel Earths have exactly the same laws of physics and infinite temporal and spatial resolution.  Would they have predicted the "warming pause"?  Well yes and no.  The warming pause is likely the effect of sources of internal variability, in fact such sources of variability are completely sufficient as an explanation of the lack of warming (e.g. Foster and Rahmstorf).  These are chaotic, and while these periods of little or no warming will be observed occasionally on the parallel Earths, they won't generally ocurr at the same time as the pause on this Earth.

    So what can we predict from the model?  Well if you take the average of the temperatures of the Parallel Earths, you will get an estimate of the forced response (i.e. the reaction of the climate to the change in the forcings, e.g. CO2).  This is what is relevant to climate policy, not the effects of internal variability which are quasi-cyclical and have little long term effect on the climate.  The forced response does not show pauses, but that doesn't mean the models are not predicting that pauses will happen everynow and again (but without being able to specify when)

    Now, lets return to real climate models, Easterling and Wehner show that these pauses are also found in the output of individual model runs as well, but again the timing of the pauses is unpredictable.  So it is unfair to say that the modells have missed the pause.  They have said we should expect them to happen, but can't predict when they will happen.

    Why should we expect real climate models to be able to predict something that a theoretically perfect model could not?

  33. Models are unreliable

    A problem I have with this entry supporting climate models is that it seems to skirt what is most critical of them.  Most current climate models completely missed the current warming pause.  This is an issue that has spawned a host of investigation.  A recent article about stronger trade winds in the media for example.  Also, it also does not address that ALL models of complex systems mispredict to some extent.  Given climate models are long term projections of where we are going, it is reasonable to expect that they will miss shorter term climate movements.  From my point of view, it is more indicative that climate models seem to still say we should be warming even after the past decade or so of flat atmospheric temperatures is taken into account.  Those who would deny that CO2 causes ANY warming or that its effect is small and not significant may point to the past decade as proof of future results.  I'd love to sell them a bridge in NY for that risky logic.

  34. Australia’s hottest year was no freak event: humans caused it

    @Barry, hi Barry, I did not change the topic so much as respond to your comment on your reference to "1990-2013, it is not the reason why 1990-2013 was hot relative to 1910-1939."  Going back 80 years does not cut it and there has been some excellent work done on the urban heat island effect which can add up to 4 degrees to a city's temperature.  The Sydney observatory is a great site for the length of recorded data but just as the Melbourne data is skewed due to location, Sydney suffers from the same problems.  I should also correct my previous post - 1889 was the very hot year.

  35. 2014 SkS News Bulletin #1: Keystone XL Pipeline

    Russ,

    It should be obvious to you following michael sweet@11, that your stance on unimportance of KXL is a big-time classic example of an individual involved in the tragedy of commons. If it is not obvious to you, please make yourself familiar with tragedy of commons and with specific examples of it in the past (sanitary waste in cities, acid rain, ozone hole, etc.).

    The individual here is a corporation building KXL and pocketting profit from it while dumping 'miniscule amount of CO2' as an externality. There are thousands of such individuals in CA alone (and many more will follow when tar sands are tapped for unrestrained exploration) each doing exactly the same, following your argumentation. Common here is the atmosphere - the dumping ground that cannot "self-clean", because the natural 'cleaning' processes are 1000s times slower than the dump accumulation. Therefore the dump (CO2) accumulates. So, if you, as an individual, contribute to 0.00683°C/century, thousand individuals can make it 6.83°C/century.

    The known tragedy of commons solutions involve (1) some form of governmental regulations, (2) individuals can cooperate to conserve the resource in the name of mutual benefit (3) conversion of common good into private property, giving the new owner an incentive to enforce its sustainability.

    In case of CO2 pollution, (3) does not work because CO2 is invisible gas. Efforts in (2) -  UNFCCC together with COP series - mostly failed so far. That leaves us with (1) - banning the further proliferation of FF infrastructure, in this case Obama's disapproval - as the only promissing method to solve (or at least alleviate) this problem.

    The alternative "laissez faire" attitude always results in such problem worsening, as we learned from the examples I mentioned above. The outcome of CO2 problem cannot be any different. If you argue that KXL does not play part in that picture please explain. I'll follow your arguments with interest.

  36. Carbon Emissions on Tragic Trajectory

    One Planet

    The return on investment cannot be ignored. If infrastructure is only required for a short duration, then the financiers need to be repaid in that shorter period. No one will lend money if only a proportion or none is to be repaid. To do so would be a donation.

    You wouldn't lend money or put money in the bank if you were not going to get it back, well not of the magnitudes required. If it was to be a donation, given that the population of developing countries is about 4 times the population of developed countries, the funds required or donation is mind boggling. 

    With 4 times as many people in developing nations as developed nations, during the transition period you suggest the CO2 emissions would dwarf the western worlds current CO2 emissions. It's just not feasible.

  37. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    Klapper:

    What about the fingerprints of the recent global warming?

    Fingerprints

    6 of the 13 fingerprints listed here are incompatible with a warming sun, 2 are neutral and 5 are related to the source of the extra CO2.

    That and comment 48 by DSL should be the end of the argument It’s the sun.
    Any further discussion about this topic probably belongs to that thread and not here.

  38. A methane mystery: Scientists probe unanswered questions about methane and climate change

    #3

    Mike,

    Methane in the atmosphere is oxydised to CO2 and water. This process is dependent of the concentration of Methane in the atmosphere as well as the ceoncentration of a catalyst (which may be fairly constant).

    This means, the more methane you have the faster it will be removed. If you have a stable emission of methane, the rate of oxidation will rise until the rate of emission and rate of removal will be equal. The concentration in the atmosphere will level out.

    a new rise in methane concentration means, that emission is speeding up again to higher levels than before. Unfortunately the mechanisms of oxidation in the atmosphere are not fully understood. If this would be the case you could read the concentration of methane as a direct proxy of emission rates.

    Note, that methane in the atmosphere has a far less remaining time than CO2. Methane will be eliminated by oxidation, CO2 can not be removed by fast working mechanisms, only by geological processes.

  39. 2013 was the second-hottest year on record without an El Niño

    @One Planet #68 #66:

    Here's a suggestion: stop pontificating about people's motives. That will not and should not win a science debate. What counts is the hypotheses they put forward and the facts they use to support those hypotheses and your countering hypothesis and facts.

    If you think the question is unfounded then address it with facts, not discussion or inuendo about the morality of people who don't agree with you.

  40. The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph

    howardlee - "I don't see how we can get heat into the deep oceans without also getting CO2 into the deep oceans."

    When the wind-driven ocean circulation is intense, such as during the negative phase of the IPO & La Nina, there is strong upwelling of cold deep water along the equator, and along the eastern coasts of the continents. This is known as Ekman suction. This cold deep water is high in dissolved CO2, and therefore there is a large flux of carbon dioxide to the atmosphere from the ocean. During the positive phase of the IPO, and during El Nino, the circulation winds down. This shuts down the upwelling and flux of CO2 to the atmosphere.

    Contrary to your assertion, there is a greater uptake of CO2 into the global oceans during the positive phase of the IPO & El Nino. Note the graph below from Keeling (1995) - taken from the SkS rebuttal on Murry Salby & CO2. The bottom figure (b) is the oceanic exchange of carbon and the blue colour denotes La Nina periods. Note how the oceanic flux is negative - indicating loss of carbon from the ocean.

    Of course the oceans are storing more CO2 over the long-term - this is why the oceans are acidifying at most likely the fastest rate (outside of an asteroid impact) in the last 300 million years. I'm just pointing out some of the complexity. 

      

    As for strong subsurface ocean storage giving more time for humans their act together, that really depends how much longer this (cool surface) phase of the circulation lasts. The recent unprecedented intensification of the trade winds may simply be shortening the length of the cycle - meaning that this negative phase may be much shorter than the previous one. We shall see.

  41. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    More from Lockwood:

    Lockwood 2008: "It is shown that the contribution of solar variability to the temperature trend since 1987 is small and downward; the best estimate is -1.3% and the 2? confidence level sets the uncertainty range of -0.7 to -1.9%." http://rspa.royalsocietypublishing.org/content/464/2094/1387.abstract


    Lockwood 2008: "The conclusions of our previous paper, that solar forcing has declined over the past 20 years while surface air temperatures have continued to rise, are shown to apply for the full range of potential time constants for the climate response to the variations in the solar forcings." http://rspa.royalsocietypublishing.org/content/464/2094/1367.abstract

    Lockwood 2007: "The observed rapid rise in global mean temperatures seen after 1985 cannot be ascribed to solar variability, whichever of the mechanism is invoked and no matter how much the solar variation is amplified." http://www.warwickhughes.com/agri/lockwood2007.pdf

  42. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    Wouldn't you have to almost completely igonore the vertical temperature profile, as well as the relative level of radiative forcing to consider solar to be the major responsible forcing?

  43. Michael Whittemore at 11:49 AM on 12 February 2014
    Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    @ terranova & @ jsam both these papers you reference look at the evaporation near Indonesia. This process is slowing due to increased evaporation from global warming. The increased trade winds have been caused by the onset of the IPO. I might be a little off, it's just what I have noted from all these denier blogs. 

  44. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    @ HK #31:

    @ Scaddenp #38:

    You're fairly sure that solar peaked in the late '50s. However, here's what Lockwood & Frohlich 2007 said about solar activity in the 20th century: "Hence, all solar trends since 1987 have been in the opposite direction to those seen or inferred in the majority of the twentieth century—particularly in the first half of that century". They don't argue that solar peaked in the late '50s. To be sure they are adament that solar could not have had an effect after 1985. I agree except I would extend that date to the mid '90s based on the aa index.

    Note the shortest length solar cycle (22 from '86 to '96) is also the most intense from the aa index, which is an indication that things weren't quite over by '85 as Lockwood asserts.

    Here's another point: say hypothetically I accept the Lockwood argument that solar rose through the first half of the 20th century, then plateaued until say the mid '80s and then declined. Since climate doesn't equilibriate immediately to changes in forcing is it not possible that this sustained high level of solar activity was responsible for onging climate change through the '80s and into the '90s? And wouldn't that be true even if the actual peak was in 1958 as you assert?

    Moderator Response:

    [TD] The lag between solar forcing and temperature response is not that long. And the moment the solar forcing flattened, the energy imbalance must start to decrease, which has not happened.  See the post "Climate Time Lag," and please comment there if you want to discuss that topic more.

  45. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    It was once considered that the ocean uptake of CO2 might be able to keep atmospheric concentrations safe, but that idea was shown to be wrong many decades ago.

    It might help, also, to put the depth of the oceans into perspective.

    The distance across the Pacific is ~6000 miles (9650 km). That is 9,650,000 meters, and the average ocean depth is ~4500 meters. In rough numbers, the Pacific ocean is about 2200X as wide as it is deep.

    The thickness of a standard piece of paper is 0.1mm, and it's about 216mm wide. Interestingly, that's about 2100X as wide as thick.

    So, while the oceans are very large bodies of water, relative to the full scale of the surface of the Earth, they are proportionately fairly thin.

  46. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    Muzz, ocean models are bound by laws of thermodynamics. You need to dream up some physically reasonable mechanism for dragging more heat deeper, faster than has been observed so far. Estimates for very deep heating (below 2000m) is constrained by steric sealevel rise. I would regard this is clutching at straws. People dont tend to explore physically unreasonsonable propositions especially when physically reasonable models are working okay.

  47. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    Muzz... What makes you think that no one has considered this idea? 

  48. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    There is always the possibility, one that no one seems to want to explore, that for the absolute possible amount of AGW that can be produced the ocean is for all intents and purposes an infinite heat sink.

  49. Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?

    dlen - trade winds and ENSO are deeply intertwined. Try this recent review article for more detail. Wang et al 2012.

  50. A methane mystery: Scientists probe unanswered questions about methane and climate change

    Mike, see Eli's post Passing Gas on the rapid but rather complicated pathway of CH4 conversion to H2O + CO2 in the tmosphere.  It is dependent on the presence of the OH radical.

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