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264 Responses to "Unforced Variations: June 2015"

  2. Not sure what your problem is. Any distribution of real numbers can be mapped into zero to one. Cantor. Starting point as Thomas notes is often one or another trig function.

    It is not clear to me whether your y values come in the range [0-1] or must be mapped there. If they come that way, well regression makes no assumption on the range of y values. As one example of what you may want batting averages which are constrained into [0-1] can make quite useable predictors.

    The key assumptions for independent variables are that they are measured w/o error (often violated to some degree but which can be corrected for with standard techniques if need be) and that they be linearly independent as a set. How does your distribution stack up?

  3. Doh. Got interested in mapping from Thomas and passed right by your own definition statement.

    Ratios are acceptable inputs to regressions so long as they meet the required assumptions. The fact that they are ratios is irrelevant. Caveat here is that if your distribution is skewed to the extremes that can cause problems and require a transform.

  5. Would it be possible to have the bore hole in reverse date order? If the answer is no it’s unlikely that many would know that I’d asked.

  6. I’m having a little trouble understanding “Climate Sensitivity” as it relates to the amount of CO2 in the atmosphere. I’ve read Skeptical Science and Wikipedia and their definitions and explanations. I know that sensitivity is based on a doubling of CO2 since about 1750 and how much scientists ‘think’ a doubling of CO2 will increase Global Average Temperature. But, future projections of 1.5 – 4.00 +/- a degree or two based on a doubling of CO2 by 2100 leaves a wide margin of error. So my question is this: Right now, with 403ppm already in the atmosphere, if we stopped emitting CO2 tomorrow are we still going to hit the 2C mark? In other words, is there enough CO2 already in the atmosphere to get us to that point or do we just not know yet? Thanks

  10. To do the fit, lets define Yi are the data values to fit constrained to be in (0,1)
    Compute Fi = atanh( 2*Yi-1 )
    Then fit to the values Fi, which are unbounded.
    The to recover the values in the original system we reverse it:
    T=.5*tanh(F) +.5
    Which has to be on (0,1)

    Note the difference between Yi of .999 and .99, is equally as significant as the difference
    between .99 and .9. Essentially we assume that the physics makes it really hard to approach either 1 or 0.

  11. Thomas…As I so stupidly missed, his distro has to stay on [0,1] by definition in the first place. Therefore my only caveat to here would be to investigate the need for any transform first.

    It appears to me that Barton was worried about the data range being constrained to [0,1] in the first place being a problem. In and of itself it is not. Such data can make fine predictors.

    As you note, the existence of a preponderance of extreme values near the extremes might require a transform of the physics. Or others problems with the distro. I am clueless about the stats concerning the normal ratio of severe drought globally, so have no idea.

    Any regression text can give him the tools to test out whether a transform is needed. I would suggest he consult, though, locally.

  13. Phenology (the recording of the timing of natural events like the arrival of swallows or the budding of plants) has show an unprecidented early arrival of Spring in the UK (& late arrival of Autumn) for some time. The BBC is reporting (not yet on line but the The Western Morning News obliges) the results of work done with The Woodland Trust & analysed by Tim Sparks of Coventry Uni that show that, when Spring does arrive in the UK today, it travels across the country 60% faster than in Victorian times. Rap-rap-rapeeedooo!!

  14. Mblanc #100

    Of course, the main source used in this article is some crazy Brit with some crazy ideas, so fringe that no one else is saying them out loud, journalists love him! – See more at: https://www.realclimate.org/index.php/archives/2015/06/unforced-variations-june-2015/comment-page-2/#comments

    Mblanc frames a credible scientist as fringe. If you want to learn the connection between seismicity and climate change, i suggest you start reading here http://rsta.royalsocietypublishing.org/content/368/1919/2311

  15. #106, 109–Thanks to Hank for that paper–it’s both succinct and highly readable. A ‘money’ excerpt:

    If emissions decrease enough, the CO2 levels in the atmosphere can also decrease. This potential for atmospheric CO2 to decrease over time results from inertia in the carbon cycle associated with the slow uptake of anthropogenic CO2 by the ocean. This carbon cycle inertia affects temperature in the opposite direction as the physical climate inertia, and is of approximately the same magnitude(1, 5). Because of the equal and opposing effects of physical climate and carbon cycle inertia, there is almost no additional unrealized warming from past CO2 emissions. If emissions were to abruptly cease, global average temperatures would remain approximately constant for many centuries, but they would not increase very much, if at all. Similarly, if emissions were to decrease, temperatures would increase less than they otherwise would have.
    (Figure 1A).

    This means that while the CO2-induced warming already present on our planet – the cumulative result of our past emissions – is irreversible, any further increase in CO2-induced warming is entirely the result of current CO2 emissions. Warming at the end of this century (and beyond) will depend on the cumulative emissions we emit between now and then. But future warming is not unavoidable: CO2 emissions reductions would lead to an immediate decrease in the rate of global warming.

    Why then are many different near-term projections of global temperature change very similar? Modeled estimates of increases in CO2-induced warming over the next two decades are similar because even socioeconomic scenarios that produce very different cumulative emissions by the end of the century are not very different over the next two decades (see Supplementary Figures 1 and 2). While the climate system physics implies that further increases in warming could in principle be stopped immediately, it is our human systems that have longer time scales. Existing carbon-emitting infrastructure such as vehicles, power plants, and buildings is designed to benefit humankind for years to many decades, and each year’s additional infrastructure of the same type implies added stock intended to last and emit CO2 for many decades. Our dependence on CO2-emitting technology therefore generates a commitment to current and near-future emissions(7). While cleaner alternatives are being developed, and carbon capture and storage is being tested, technological development and diffusion is subject to substantial inertia(8). Thus societal inertia, rather than the inertia of the climate system, is the critical driver for urgency if we wish to begin to decrease the rate of CO2-induced global warming in the near future.

    The paper goes on to discuss the ‘carbon budget’ concept, and also makes the point that was my initial reaction to Chuck’s question: since we’re as yet unable to constrain climate sensitivity more tightly, we are limited to probabilistic statements about the ‘chances’ of avoiding 2 C (or not.) Basically, at present we can’t be sure of avoiding it, but if we try really hard we have a pretty good chance.

    On the other hand, if climate sensitivity turns out to be at the high end, we may hit 2 C despite really strenuous mitigation efforts. It’s not the best position to be in–particularly considering that the adequacy of the 2 C buffer has been seriously questioned by Hansen and others–but it could certainly be worse.

  18. @ Hank:

    I read this paper and it seems to imply that if we stopped emitting CO2 today global temperatures would stop rising…. if I read it correctly.

    For Chuck Hughes: http://dspace.mit.edu/handle/1721.1/87694

    If that be the case, then is there any lag time between CO2 levels and GAT or do they work in tandem? In other words, global temperature would not have to catch up with CO2 levels, meaning there’s no extra heating “in the pipeline” once CO2 emissions cease.

    Is that correct? I was looking at CO2/GAT charts over long timescales and the lines crisscross each other but seem to stay pretty close together for the most part. BUT…. we’re raising CO2 levels so quickly it seems to me that GAT would still have some catching up to do. I’m just trying to get this straight in my head. Thanks for you help.

    This is one of the graphs I found but there were several:

    https://royalsociety.org/~/media/Royal_Society_Content/policy/projects/climate-evidence-causes/fig3-large.jpg

  19. The latest El Nino report put out by the National Weather Service’s climate prediction center includes a grid provided by IRI/CPC on which the predictions of over twenty agencies are arrayed. Interestingly, the most bullish of the El Nino predictions, forecasting that a very strong one will persist through mid-winter, comes from our very own NASA Goddard Space Flight Center’s “Global Modeling and Assimilation Office.” As an admirer of Gavin’s work on behalf of educating the public on climate change, and of his broad knowledge of the field, and having an understanding that he is the Director of the NASA Goddard Institute for Space Studies in New York, one is compelled to ask: why is NASA GMAO so bullish on the El Nino?

    [Response: GMAO is a separate office in GSFC in Greenbelt. While we work with them on a number of issues, I don’t have any particular insight into their ENSO forecasts. – gavin]

  20. jgnfld. Some data if it doesn’t stray too close to the limits, and doesn’t have much noise, and closely matches the “shape functions”, might work without a transform. But if it goes close to those limits, then you’d like the transform to reflect how hard it is to approach those limits. atanh/tanh is the most likely best guess, as it would be natural if quantities exponentially approach the limits. The physics could of course dictate something else. Hopefully he can get low residuals with a low order fit. If not, perhaps another transform is more appropriate.

  21. > Chuck Hughes … read this paper. It seemed to imply …

    I don’t rely on my own reading, let alone what I think it may seem to imply (few scientists would leave such a conclusion implicit, it would be stated).

    It’s easy to fool myself to thinking a paper says (or worse, even implies) some assertion that I’d like to see and reblog. Pitfall, that.

    Science doesn’t work that way — an answser based on one paper — regardless.

    Which means: read some of the citing papers.

    That’s always a link at Scholar (assuming anyone thought the paper worth citing, as a dozen subsequent papers already have for that one).

    Here’s one of the citing papers:

    http://iopscience.iop.org/1748-9326/9/12/124002
    Environmental Research Letters Volume 9 Number 12
    Katharine L Ricke and Ken Caldeira
    2014 Environ. Res. Lett. 9 124002
    doi:10.1088/1748-9326/9/12/124002
    Maximum warming occurs about one decade after a carbon dioxide emission

  24. On the other hand, if climate sensitivity turns out to be at the high end, we may hit 2 C despite really strenuous mitigation efforts. It’s not the best position to be in–particularly considering that the adequacy of the 2 C buffer has been seriously questioned by Hansen and others–but it could certainly be worse.

    Comment by Kevin McKinney — 12 Jun 2015 @ 4:59 AM

    Thank you Kevin!

  26. Re: 106,109,115:

    This paper tells us what was already known and what I have tried to tell you all for a very long time: Pull down CO2, cool the planet, possibly on a time frame to not only avert 2C (though I think ocean heat content, CH4, general mayhem in the Earth system will make CO2 and temp reversal a bit more dicey than the quote at 115 implies left to non-anthropogenic efforts), but but cool the planet quickly to arrest SLR, at least on the scale of a century or two.

    I’ve asked many times for this to be modeled. Apparently someone kind of did.

    So, simplify, forest, aforest, etc., etc., and this paper says we can do what I’ve suggested.

    Good news. Glad someone rounded this up.

  27. Heard on the news that reports of significant australian aviation turbulence has risen from what was an average of around 88 events/year to now over 450. The main factor stated that changes in the jet stream are causing this increase… Interesting? Seems as though changes in the jet streams are causing many types of changes globally.

  28. 119 S.B Ripman: Depends on what side of the pacific your perspective of ‘bullish’ lies. We in Queensland Australia especially out west are experiencing their worst ever drought. 80% of the state has been declared drought stricken. Indeed California needs rain – but so do we!

  29. 128 Lawrence Coleman: I’m constantly telling my denialist friends and family that they need to stop being so parochial, that they need to realize that we’re dealing with global phenomena. But mea culpa, mea maxima culpa!

  30. #113 MARodger “unprecidented … for some time” So not actually unprecedented after all. Disappointing really.

  31. Chuck, #118–“If that be the case, then is there any lag time between CO2 levels and GAT [which I take to denote “Global Average Temperature”] or do they work in tandem? In other words, global temperature would not have to catch up with CO2 levels, meaning there’s no extra heating “in the pipeline” once CO2 emissions cease.

    “Is that correct?”

    – See more at: https://www.realclimate.org/index.php/archives/2015/06/unforced-variations-june-2015/comment-page-3/#comment-632237

    I think that Hank’s points above regarding this question are well-taken. However, I’m going to go ahead anyway and say that I think the short answer to the last question is “yes.” It’s consistent with previous discussions here, IRRC.

  32. #123, Hank–No, that post is talking about a situation with constantly increasing CO2e:

    “TCR is clearly defined–the GMST change expected from a 1% per year increase in RF CO2 (or an equivalent RF from all sources, CO2eq)…”

    So it’s not relevant to the question Chuck is asking–ie., “What happens if emissions cease abruptly somehow?”

  34. simon abingdon @130.
    My apologies. I shall re-write that sentence @113 with less ambiguity.
    For some time phenology (the recording of the timing of natural events like the arrival of swallows or the budding of plants) has show an unprecidented early arrival of Spring in the UK (& late arrival of Autumn).
    Of course, this absence of precident is but evident within the UK records that stretch back to 1738. Prior to that, well, who knows.

  35. > “What happens if emissions cease abruptly …”

    Try: “cease emissions from human activity burning fossil carbon and cease production and/or release of other greenhouse gases, natural and artificial”

    We don’t know that we know all possible feedbacks. Some may have already begun to operate. Things we know are going to happen — melting the Arctic and Greenland over coming centuries, for example. That may both release more CO2 and recycle more CO2. Changes in the ocean biota — will those favor plankton effective in capturing CO2 and turning it into sediment? Or plankton good at recycling CO2 from the ocean and releasing greenhouse gases into the atmosphere?

    Just guessing, of course. Stay tuned for the science.

  37. Thank you Hank!! I took this from the Skeptical Science article and I assume it is still valid. (2010)?

    http://www.skepticalscience.com/Climate-Change-The-40-Year-Delay-Between-Cause-and-Effect.html

    “The estimate of 40 years for climate lag, the time between the cause (increased greenhouse gas emissions) and the effect (increased temperatures), has profound negative consequences for humanity. However, if governments can find the will to act, there are positive consequences as well.

    With 40 years between cause and effect, it means that average temperatures of the last decade are a result of what we were thoughtlessly putting into the air in the 1960’s. It also means that the true impact of our emissions over the last decade will not be felt until the 2040’s. This thought should send a chill down your spine!”

  38. The study contrasts this outcome with an admittedly impossible but still instructive scenario — one in which, in the year 2035, concentrations of carbon dioxide suddenly and inexplicably go back to their 1850 levels. This, too, cools the planet rapidly. But it would also help stabilize the glaciers.

    Cool the planet, stop WAIS collapse!

    Impossible? Bull. That is stated out of complete ignorance of what can be done to sequester carbon with land use changes, primarily putting carbon in the soil via changes to farming, gardening, grazing (meat consumption), and forests, as well as the vital massive reductions in consumption among industrialized nations.

    BUT!!!!! What is great is, as many of you know, I have asked for this scenario to be modeled for years. BEGGED for it, knowing it is actually possible, and simple to achieve. Wow. We can cool the planet AND stabilize the ice sheets. I knew we could do the first, but had no idea if we could do the second in a timely manner.

    SOLUTIONS, BABY!!!!

    Contrast all this with just geoengineering with sulfates.

    In the climate simulation employed by McCusker and her colleagues, in the year 2035, humans begin pumping 8 million metric tons of sulfate per year into the atmosphere for three years, and then increase it further annually after that. This definitely works to cool down the planet, ramping temperatures down to late 20th century levels within a decade. But the glaciers of West Antarctica continue to melt.

  40. “The fact is the pontiff is already building an army of billions, in the same spirit as Gandhi, King and Marx. These are revolutionary times. Deny it all you want, but the global zeitgeist has thrust the pope in front of a global movement, focusing, inspiring, leading billions. Future historians will call Pope Francis the “Great 21st Century Revolutionary.”

    Yes, our upbeat, ever-smiling Pope Francis. As a former boxer, he loves a good match. And he’s going to get one. He is encouraging rebellion against super-rich capitalists, against fossil-fuel power-players, conservative politicians and the 67 billionaires who already own more than half the assets of the planet.

    That’s the biggest reason Pope Francis is scaring the hell out of the GOP, Big Oil, the Koch Empire, Massey Coal, every other fossil-fuel billionaire and more than a hundred million climate-denying capitalists and conservatives. Their biggest fear: They’re deeply afraid the pope has started the ball rolling and they can’t stop it.”

    http://www.marketwatch.com/story/no-1-reason-popes-climate-encyclical-scares-gop-big-oil-far-right-and-super-rich-2015-06-13

  42. Cheer up Chuck: Rome was not sacked in a day; do you expect UBS to send its Swiss guards south for a replay of 1524?

    Climate policy needs the Pope like a fish needs an encyclical

  43. Dredd, Sudden sea level rise.
    That article reads to me as basic fearmongering. Equating glacial meltponds with ice dammed great lakes just isn’t correct. The scale is vastly different, may tens of kilometers cubed, versus a few million cubic meters. There just are no gigantic ice dammed lakes today, although there are subglacial lakes in Greenland and Antarctica. But the sort of volumes needed to cause a meter of SLR just don’t exist. And the east coast SLR event, was due to changes in ocean currents and winds, and isn’t related to global SLR.

  45. That “renewables” are not sustainable is self-evident, though the vast majority of people you say this to will argue the point as if you’re a crazy Luddite who wants everyone to live in caves, and preferably die. At least so it seems.

    Here at RealClimate, even, there have been those he have attempted to refute this. Well, here ya go. Wind down…

    Wind Turbines Unsustainable

    In conclusion we obviously cannot build wind turbines on a large scale without fossil fuels.

    Now, none of this is to argue against wind turbines, it is simply arguing against over-promising what can be achieved. It also should be pointed out that we cannot build a nuclear power plant, or any piece of large infrastrtucture for that matter, without concrete or steel. A future entirely without fossil fuels may be desirable, but currently it is not achievable. Expectations must be set accordingly.

  46. Re 141 Dredd said I ran across a scientific paper (NASA GISS) which indicates that in the recent geological record is evidence of a 1m / 3ft sea level rise that took place “within a few years or less” (The Surge: A Forgotten Aspect of Sea Level Rise).

    It took place about “8,200-7,600 years ago” when early civilization was taking shape.

    You need to read it again. There is a massive difference between one massive, mid-continent, ice-dammed lake that was truly massive – like, Caribbean large – emptying at one time vs a bunch of truly tiny melt water lakes that are periodically forming and draining.

    While I think we could see some pretty rapid SLR, that comparison is very wide of the mark.

  47. Jeeze this place is getting grumpy. Russell thinks the Pope is no big deal, then Killian tells us (surprise) that with current methods at least we need some fossil fuels to build infrastructure like wind turbines, so using zero fossil fuels “currently it is not achievable.” Strawman much?

  48. K 145: That “renewables” are not sustainable is self-evident

    BPL: A lot of things are “self-evident” to you that other people cannot even figure out. I know I can’t.

  49. Climate policy needs the Pope like a fish needs an encyclical

    Comment by Russell — 14 Jun 2015

    Your point being…..?

  50. #145–Yes, and in the comments the author writes:

    “What really matters is that it takes much less fossil fuel to make wind electricity than is in an equivalent amount of fossil fuel energy. The aim to take things to zero is a distraction from the aim to reduce.”

    A rather more nuanced view.

    I certainly note K’s alternative pathways to decarbonization, and await sizable demonstrations of their practicality. In the meantime, I think that scalable carbon-free–or, if you prefer, ‘lower-carbon’–energy generation is really, really, important to encourage, abet, and recognize.