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General Climate Discussion (1)

Posted on by SJ in Uncategorized

Update: Please head over to the new Discussions page!

Due to the incredible (and continuing) response in the comments on my post about Guy McPherson, I’m creating a fresh thread for general discussions or questions about climate here. Any comments specific to the Guy McPherson post can continue there.

625 thoughts on “General Climate Discussion (1)”

  1. So if we just stablize CO2 at todays levels, we’ll be ok?

    I keep hearing about all these new technologies that are going to free us from foreign oil (though I suppose US oil isn’t hugely cleaner than foreign oil), been hearing that for about as long as I can remember. And all these theories about oil companies squashing them or buying them out. One way or another, it appears we’re wedded to oil ’till death do us part’.

    Talk about confusing, I offer these two articles both published yesterday,

    California just had its worst drought in over 1200 years, as temperatures and risks rise
    Global warming is playing havoc on extreme weather
    http://www.theguardian.com/environment/climate-consensus-97-per-cent/2014/dec/08/california-just-had-its-worst-drought-in-over-1200-years

    California drought ‘not caused by global warming’, official study finds
    http://www.theguardian.com/us-news/2014/dec/08/california-drought-not-caused-by-global-warming-official-study-finds

    Here’s one more for your analytical mind to ponder over,

    The End and Beginning of the Arctic
    http://www.climatecentral.org/news/the-end-and-beginning-of-the-arctic-18407

    Adapting to a warmer climate could cost almost three times as much as thought, says UN report
    http://www.theguardian.com/environment/2014/dec/05/adapting-to-a-warmer-climate-could-cost-almost-three-times-as-much-as-thought-says-un-report

    Julie Bishop steps up lobbying to stop Great Barrier Reef being listed ‘in danger’
    http://www.theguardian.com/environment/2014/dec/09/julie-bishop-lobbying-stop-great-barrier-reef-listed-in-danger

    On the oil question, this is my gut reaction. Climate Change or no, unless a new miracle technology suddenly explodes on the world scene, one that can power not just our factories, heat our homes and run our cars, and we have the will and the money to impliment it, oil use isn’t going anywhere but up.

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    1. So if we just stablize CO2 at todays levels, we’ll be ok?

      Ideally, we’d like to stabilize and then bring it down a bit. If we stabilize at 400 ppm and it stays there for a hundred years, warming will gradually continue— but it would be absolutely fantastic if that’s all we had to worry about instead of our current predicament.

      Re: California drought studies.
      An author of the first study you linked there discussed this on Twitter, if you scroll back to Dec. 8th (I’m too lazy to pull these together right now): https://twitter.com/thirstygecko
      Another John did a pretty good job with this: http://arstechnica.com/science/2014/12/californias-drought-declared-natural-by-noaa/
      Basically, it’s a complicated question.

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      1. john asked:
        So if we just stablize CO2 at todays levels, we’ll be ok?

        sj wrote:
        Ideally, we’d like to stabilize and then bring it down a bit. If we stabilize at 400 ppm and it stays there for a hundred years, warming will gradually continue

        That’s awfully vague, Scott. For how long and how much (will it rise gradually)? What do you think are the best estimates? For instance, Wadhams says + 2C by 2100. Hansen said in 2007 0.5 – 0.75C without a timeframe (but I’d bet he’d give you one if you asked!). Caldeira said 40 years and then changed it to 10 years. He didn’t say by how much and he didn’t answer when I asked.

        sj wrote:
        Another John did a pretty good job with this: http://arstechnica.com/science/2014/12/californias-drought-declared-natural-by-noaa/
        Basically, it’s a complicated question.

        Gee, we seem to be having a run on multi-century events. What’s the chances of that happening?

        Once-In-1200-Year California Drought Bears Signature Of Climate Change

        Recent peer-reviewed studies strongly support the view that California’s epic drought was made considerably worse by human-caused global warming. A new NOAA report seeking to cast doubt on that assertion omits some of the latest science and is deeply flawed, as three leading climatologists told me.

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      2. That’s awfully vague, Scott. For how long and how much (will it rise gradually)? What do you think are the best estimates?

        Here’s an answer published several years ago: http://www.realclimate.org/index.php/archives/2010/03/climate-change-commitments/
        I wish I’d found this for you a week ago…
        Click the first link (to the Matthews and Weaver paper) and you’ll be able to read it. (Nature has this new initiative providing access via links from some websites. Details: http://arstechnica.com/science/2014/12/nature-expands-access-to-papers-in-its-family-of-journals/)

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      4. Really? There are only two links in that post, and I’m talking about the first one, in paragraph one. I’m still figuring this system out (and what kind of use is allowable…), but you might even just be able to click here. [Edit: Link removed since it wasn’t necessary.] That link might work even though you’re not clicking through from RealClimate. After a moment, it should pop right up instead of showing you the usual abstract page.

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      5. Oh, yeah, I’m getting that Matthews and Weaver letter. I was hoping for a more detailed paper. I thought you were talking about the Wrigley paper.

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    2. “So if we just stablize CO2 at todays levels, we’ll be ok?”

      Hah. Well even supposing “… if we … stablize CO2 at todays levels, we’ll be ok”, it’s the “just” bit that implies that is even possible (and I mean that in a practical/reality sense), which seems like a wild fantasy to me. I’m glad Scott used the word “predicament” because there really is no solution to what we’ve unleashed and continue to worsen. For example, the West Antarctic Ice Sheet now looks to be in irreversible (in time periods relevant to human lifetimes) decline and ocean acidity is rapidly increasing. What we need now is the impossible and guess what the characteristic of “impossible” is.

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    3. sj wrote:
      “Basically, it’s a complicated question.”

      “It was complicated officer. I hated him. I pulled the trigger. But, don’t you see… ”

      I was on the press call with Hoerling and Seager, and asked them why they focused on the precipitation deficit and mostly ignored the unprecedented recent warming. The answer they gave was that precipitation is what this drought was about. As evidence, they said farmers “were praying for rain, not cooler temperatures.”

      Yes, as impossible as it sounds, Hoerling actually said this.

      The logic of the study further implies:

      By our definition, the drought was not so bad. What you experienced in terms of actual dryness has little or nothing to do with what kind of drought you had.

      “What you experienced is not what actually happened.”

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      1. Funny that an author of the “worst in 1,200 years” paper wasn’t nearly as mocking and derisive as you…

        Why even post this, four months later? What’s the point, other than to be obnoxious?

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      2. sj wrote:
        Funny that an author of the “worst in 1,200 years” paper wasn’t nearly as mocking and derisive as you…

        James Hansen often remarks about the difference between what scientists will say or claim in a formal setting and what their opinions would be in the bathroom. This comments section, judging by the tone, is the bathroom. I doubt that author would be so restrained in the bathroom.

        sj wrote:
        Why even post this, four months later?
        Feel free to put my post where I had intended to post it.

        sj wrote:
        * What’s the point, other than to be obnoxious?*

        I feel the response was commensurate to the provocation: irrational, “motivated”, damaging science.

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      3. James Hansen often remarks about the difference between what scientists will say or claim in a formal setting and what their opinions would be in the bathroom. This comments section, judging by the tone, is the bathroom. I doubt that author would be so restrained in the bathroom.

        Baseless bullshit. If you would actually bother to read the series of substantive tweets I pointed you to (and note other drought researchers chiming in), you might get something from it. Instead, it’s just another thing for you to wave away with invented epicycles. You just know that Hoerling is a foul scoundrel who’s always wrong, because he’s a “denier”, and nothing in his research can have any merit whatsoever. So if other scientists seem to treat his research differently, then by god, they’re cowards who can’t tell the truth.

        Feel free to put my post where I had intended to post it.

        Unfortunately, the software doesn’t let me do that. And the comment is no more relevant here than it is there.

        I feel the response was commensurate to the provocation: irrational, “motivated”, damaging science.

        Can’t even guess what you’re on about here. Done trying.

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    1. Details. It’s like quantifying the things we’ve been thinking about in broad strokes. Lots of work like this to be done, though, mapping out various areas, as factors like bottom water warming and fate of released methane will vary a lot from place to place.

      For context, their “up to 0.4 million metric tons of methane” (of which none may reach the atmosphere) would be about 0.07% of the estimated annual global methane release.

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      1. From the Real Climate article,

        “We are clearly not going to get to zero emissions any time soon, and even the 60-70% cuts required to stabilise concentrations initially seem a long way off.”

        Yep, I have to agree with that statement. We use oil for EVERYTHING. Runs our factories, powers our vehicles, paves our roads, heats our homes, it’s the biggest component of just about everything we make and of course it overflows our landfills. Even our friemdly neighborhood plastic bag may have a 1,000 year life in the environment before it breaks down into tiny plastic pieces.

        http://www.slate.com/articles/news_and_politics/explainer/2007/06/will_my_plastic_bag_still_be_here_in_2507.html

        Population is going up, the infrastructure is in place, neither the will or the money is there for a fix and there is nothing that can realistically replace oil. My gut tells me we’re in this for the long haul.

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  3. This is interesting. A press conference from the AMEG people. The conference took part over three days, each day is available on youtube. Essentially the information was repeated thrice over those days so here is just the final day. It was more comprehensive than the two previous days. Paul Beckwith is among the scientists represented. SJ, I know you’re going to groan but I still think it’s worth a view.

    Incidentally, the solution to CC that they propose is geoengineering. I have to say, I’m very uncomfortable with that. A few days ago I was listening to a lecture by scientist and author Ben Bova wherein he states that the solution to CC is to somehow physically move the earth into a more favorable orbit and then he quipped, “And I know how to do it.” If geoengineering on that scale doesn’t make you uncomfortable, I’ll have what you’re drinking.

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    1. That link wouldn’t play for me, but I found it here: http://unfccc6.meta-fusion.com/cop20/events/2014-12-04-12-30-abibimman-foundation-united-planet-faith-science-initiative/abibimman-foundation-united-planet-faith-science-initiative-2

      I knew this was coming, as I got a press release about it a week or two ago.

      I watched chunks of it. Oy, what a mess! Amateur hour.

      Geoengineering is an interesting and complicated topic. The kind of solar radiation management they’re talking about isn’t a solution, it’s a stop-gap. There are plenty of risks and drawbacks, but some scientists are putting in the research in case we someday decide it’s necessary…
      Here’s what the last IPCC report had on the topic: http://arstechnica.com/science/2013/10/geoengineering-through-the-eyes-of-the-ipcc/

      I’ve certainly never heard that suggestion about changing Earth’s orbit! I think I’ll pass on what he’s drinking.

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      1. Yes, quite amateurish but that’s not really important. However, I don’t think there was enough there to give any kind of confidence that there is an Arctic methane emergency. And cherry picking graphs doesn’t help – where are the data points for the last two years of Arctic sea ice minimums? They were certainly available but don’t bolster the emergency method and so were excluded. That is the denier’s way of presenting data.

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      2. I actually don’t think it rises to that level of manipulation. It’s just that they don’t work with data— they just have several images they’ve been talking about for years, and don’t know how to update them, or pay attention to whether updating them would matter.

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      3. Not sure I get what was ameteurish, but leaving out the last two years weakens the credibility and the message.

        I’m really curious what Francis comes up with in her new modeling study which applies her jet stream theory to the sea ice problem.

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      4. Oh, the amateurism (for me) was with the poorly scripted slides, the trouble with the microphone, the poor delivery by John Nissen, and so on. The adulation of their engineer who dreamed up the untenable geo-engineering method that they’re promoting didn’t help either. All of that doesn’t really matter, as I’d said (I hope the later presentations were smoother), but it was entirely unconvincing anyway.

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      5. I would include the content in that description along with the form. This is your big shot trying to attract attention at a major event and you present… nothing.

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      6. Meanwhile at the other end of the spectrum…

        Just saw my first fracking commercial (which probably means I don’t watch the tube much). It’s clean, it’s safe, it will make you money, it’s good for the country. Warm, fuzzy, slick. But it makes me feel kinda sick.

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  5. One link I’m just sharing, one I have questions on.

    The one I’m just sharing: http://www.carbonbrief.org/blog/2014/12/why-arent-climate-models-better-at-predicting-arctic-sea-ice-loss/

    The one I have questions on: http://onlinelibrary.wiley.com/doi/10.1002/qj.2450/abstract

    I got this from the forum connected to Neven’s Sea Ice Blog, a forum that has a number of what you might call “McPherson-Lites;” they may not be calling for Apocalypse Now, but they accept any study/write-up/blog that makes our situation out to be worse than the current consensus without reservations. Lately, some of them have been posting link after link that they say prove that ECS is significantly higher than 3C, higher even than 4.5C. Most of the links don’t actually seem to deal with ECS, but this one did. My problem is, I have no idea what half of it is saying.
    My questions:
    1. What is “convective mixing?”
    2. What are Earth Systems Models, and how do they differ (if at all) from a climate model?
    3. The range mentioned for this model is way above the standard estimate. Does that represent some radical new breakthrough that calls for rethinking ECS, or is it due to this model dealing with tropical circulation and not factoring in everything else that affects climate sensitivity?

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    1. You can read it here, but it’s a complicated one: http://pubman.mpdl.mpg.de/pubman/item/escidoc:2007690/component/escidoc:2069570/qj2450.pdf
      1- Convective mixing is a reference to turnover in the atmosphere due to convection— heating from below that causes air to rise and cooler air to take its place. Here they’re focused on representations of that in the tropics, and how that affects the strength of the larger circulation (Hadley) cell, where warm moist air rises from the equator and comes back down around 30 N/S. http://en.wikipedia.org/wiki/Hadley_cell
      2- It’s just a labeling thing— Earth System Models are those that have the most components, like carbon cycles. You can have General Circulation Models of just the atmosphere or ocean, or global climate models with both and more (like sea ice).
      3- Folks claiming this has major implications for ECS haven’t looked at it. If you jump to the conclusions section at the end of the paper, you should be able to grok the gist. They were basically doing an experiment where they fiddled around with the values of 8 key parameters in the model (for things like convective mixing), running about 100 combinations. They found that several parameters affecting convective mixing had the biggest impact on the ECS of the model in any given configuration. (The 10C end of their range is actually an arbitrary pin for several configurations that would have resulted in even higher sensitivities. Most of them are between 4-8C.) It’s not implied that any of these results are more or less realistic. I think the current working version of the model they’re using has an ECS of 4.3C, by the way (according to Table 9.5 of AR5).

      Actually, the paper makes an interesting point that a couple studies finding higher sensitivity models did a better job of simulating some key cloud processes probably don’t mean much. You’ve probably seen this one before: http://www.sciencemag.org/content/338/6108/792.short

      Anyway, here’s the kernel: “There is a temptation to take this result as being indicative of high climate sensitivities being more probable, which would agree with the inferences made by Sherwood et al. (2014) and Fasullo and Trenberth (2012) [the one I just linked above] on somewhat different grounds. However, given the importance of convective mixing in the lower tropical troposphere to the climate sensitivity, and being cognizant of the fact that it arises from poorly understood interactions of admittedly crude representations of convective processes through the depth of a troposphere that is not well resolved, one hesitates to jump to such a conclusion. Given that climate models tend to underestimate entrainment of environmental air in deep convective processes (Kuang and Bretherton, 2006; Oueslati and Bellon, 2013; Sherwood et al., 2013), if anything the results of the simulations suggest the opposite inference, namely a more modest climate sensitivity.”

      Interesting paper and good questions.

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      1. Thanks for the answers. Is there any particular reason for using 4.3C as the ECS value in this model, or was it an arbitrary figure?

        The same guy who posted that frequently expresses an opinion (which he tied that study into) that goes something like this: the PDO and AMO are both about to become positive, which will cause accelerated warming in the North Atlantic and Pacific plus the Equatorial Pacific, which will increase El Nino weather, which will trash rainforests and reduce local cloud cover, which will send solar radiations shooting up, which drives up ECS, and so on.

        This could be solid science and sound predictions – I don’t really know anything about ocean oscillations. But I’d be curious to know what the current projections are for warming in the Northern latitudes. That, and a quick Wiki check (not always a great source, I know) suggests that the AMO is currently in a warm phase. I thought that WAS positive?

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      2. Ah, ECS isn’t chosen or deliberately set. It’s the result of how all the other processes in the model play out. In other words, it’s not an input, it’s an output.

        Pinning the current slowdown on PDO certainly isn’t crazy, and you can expect that to reverse at some point. That’s no trigger for some runaway, though, and it certainly wouldn’t change ECS— that just is what it is.

        Yeah, Wikipedia isn’t lying to you, those graphs are pointing back to good data sources. AMO isn’t turning upwards.

        What do you mean by current projections for the Northern latitudes?

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      3. “What do you mean by current projections for the Northern latitudes?”

        Just that, since the guy named North Atlantic/Pacific specifically, and seemed to think that they were in for “accelerated” warming, what was currently expected for those regions in the near future?

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      4. Oh, okay. That kind of thing (ocean oscillations) is too hard to predict. I haven’t heard anybody talking about anything wild, though.

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  6. CO2 emissions and atmospheric content. The relationships are interesting as are the changes in rates. Big spike in rate starting in 1944. A leveling from 1912 to 1944 — from the beginning of WWI to the end of WWII.

    I don’t completely trust the emissions data. The earlier years are suspect, maybe even into the twentieth century.

    The U.S. State Dept, in 1945, called the oil reserves of the Middle East “a stupendous source of strategic power, and one of the greatest material prizes in world history” and from then on considered themselves the owners. This is partial quote and partial paraphrase of Chomsky.

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    1. bill shockley wrote:
      Big spike in rate starting in 1944

      I should have said big spike in rate of increase starting in 1944.

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  7. This looks right now. Had the wrong weight for a mole of air. May still need some fine tuning.

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  8. I’ve been working on a simple model to illustrate my view of what’s going on in our Joos-Ricki-Caldeira controversy. I use global emissions data as inputs and get varying CO2-level output curves depending on how I assume CO2 will leave the atmosphere. What I call the decay profile.

    This is my model’s user interface:

    The tiny chart in the upper left is the decay profile. It is adjusted by playing with the parameters in bold in the colored rows. Some featured inputs and outputs are in the cells next to the profile chart:
    –Beginning ppm in 1900 (300ppm) where the model begins its calculations.
    –The maximum ppm it gets to (383ppm), which happens in 2008, the last year CO2 is injected (because of the data source).
    –T10ppm which is the CO2 level 10 years after emissions are halted (378ppm). They have fallen 5ppm.
    –And TENDppm which is the ending CO2 level in 2139 (364ppm), the longest I was able to run the program as it is setup now. The limiter was the number of columns in an Excel spreadsheet (256). That was the reason I started in 1900—otherwise I would have started in 1751.

    This graphic shows the fidelity between the model and the real world:

    My first guess was remarkably close—I just had to adjust the beginning CO2 level in 1900 by 2ppm to get a perfect fit. That’s called fudging, but it doesn’t matter at this point for what I’m trying to show.

    This one shows 2 outputs side-by-side, together with their respective inputs:

    The only difference between the two is the decay profile for injected CO2. The one on the left assumes a higher equilibrium level, .54 vs .4. That’s the level on the tiny chart that the tail is centered around. It’s basically a number for the balance between ocean and air CO2. Also, the one on the right has a steeper declining tail, so CO2 will decrease more in the next century and beyond with that profile and previous years long ago will not contribute so much to the present levels.

    My preliminary conclusion is that CO2 levels don’t necessarily fall off that much in the scenario where emissions would stop abruptly. This model doesn’t prove it, but it shows what would happen if you assume some things that are not difficult to believe are true, i.e, the position of the ocean-air equilibrium and the natural decay rate of CO2 in the atmosphere once ocean and air have balanced out–so, the scenario that results is not necessarily that far removed from the ECS “constant CO2” assumption. The model also has the ability to support conclusions by showing fidelity with actual data (the mauna loa curve).

    Anyway, I’m hoping this is a starting point for clearer discussion.

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  9. http://www.livescience.com/49184-permafrost-disappears-from-alaska.html

    This is another piece where I’m interested in possible discrepancies between the headline and the content. The title, and the writing, make it sound as if nearly all the permafrost will disappear all over Alaska, but the study that’s being written about only seems to have looked at specific national parks. That larger claim of the headline also seems at odds with that map (I think it’s been posted on here) showing the best estimates for how much permafrost will remain by 2100. Did I miss something about the study/its implications?

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  10. I don’t mean to keep bringing over links (and opinions of links) from Neven’s forum, but I honestly haven’t met anyone over there who I think would answer questions without filtering everything through the lens of pet theories.

    Someone just shared this study: http://onlinelibrary.wiley.com/doi/10.1002/2014JG002685/abstract

    And the write-up of said study: http://phys.org/news/2014-12-methane-leaking-permafrost-offshore-siberia.html

    Since I don’t have access to the full study, I don’t know if it discusses timescales or amounts (the guy who shared this predicted 2-3 decades, but that wasn’t supported by a quote from the study). I see in the write-up a mention of “explosive gas release from the shallow areas,” but that’s not very satisfying. And the one preview page cites Shakhova, but the abstract and the write-up don’t give any indication on whether these new findings support their predictions on how much methane can come out how fast.

    Anyone else come across this?

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    1. I can’t access those papers at the moment, so I’m in the same boat. Timeframe and significance unclear. Sounds interesting, though.

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      1. I sprang 6 bucks for the rental. There doesn’t seem to be any discussion on timeframes or potential emissions; the conclusion only discusses the possible extent of marine permafrost.

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  11. The second incarnation of my model is here. I sacrificed speed for vista and significance. The old model would run in 4 seconds and covered 240 (1900-2140) years. The new one runs in 41 seconds to cover 260 years (1750-2008), and 113 seconds to cover 550 (1750-2293) years. The 10X speed difference per year is because excel is doing most of the calculations on the shorter/faster one, so they are being done at a very low level of code.

    This is the new user-interface:

    The decay profile looks more angular because it is covering 550 years rather than 100 in the old version, so it is more compressed, horizontally.

    This is how the complete output looks:

    My main objective for doing this second version was to find out what is a good starting ppm for 1900? I was guessing when I chose 300ppm and then modified it to 298 to get a good fit with the decay profile. Now, starting in 1751 @ 280ppm, there was no plausible decay profile that would fit the emissions data and also line up with the Mauna Loa curve. Mauna Loa, I believe, is accurate, since it is a modern data set. The emissions data is old, but consistently computed, so there is some reason for trust there, at least in certain ways and to a certain extent. It would have continuously evolved from how it was calculated and collected in 1751 to how it is done now. 294.5ppm is about as low as I can go for a starting point @1751 and still get a good fit with a plausible decay profile (main criterium is that it plays out to about 25% after 1000 years). I’m not sure what to believe about the 280ppm mark for 1751. I’ve also seen 270ppm for pre-industrial. The two things that can’t change much are the decay profile and the Mauna Loa data. It would really have been great if Keeling had come along about 50 years earlier.

    All this is being done to help me visualize what is being said in the Ricke-Caldeira paper and what significance and meaning it has. I have a few more things to research for that.

    But now I’m really curious what is considered the best guess for pre-industrial CO2 ppm and how people have reconciled it with the Mauna Loa curve. I would like to hear that there is some support for a higher level, as my calculations suggest. It would make things easier for me.

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    2. Thanks for the paper. Vavrus is a trusted source :)

      So, EPICA ice core measurements put CO2 @ 279 in 1744 if I have pulled the graph data properly.

      But, also, I can infer from your paper that fossil fuels aren’t the only significant contributors since 1750, but also agriculture and feedback from temperature rise, too, right?

      In which case, there is probably plenty of room to reconcile the FF emissions, the Mauna Loa chart, and the 280ppm start in 1751 with a plausible decay profile. All I needed was an extra 14 ppm of CO2 emissions.

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      1. Actually, here you go, from AR5 Section 8.3.2.1 “The tropospheric mixing ratio of CO2 has increased globally from 278
        (276–280) ppm in 1750 to 390.5 (390.3 to 390.7) ppm in 2011 (see Section 2.2.1.1.1).” http://www.climatechange2013.org/images/figures/WGI_AR5_Fig8-5.jpg (Which is too compressed to be helpful.)

        Land use has had a small cooling influence via increased albedo: http://www.climatechange2013.org/images/figures/WGI_AR5_Fig8-9.jpg

        Carbon budget is chapter 6. “Anthropogenic CO2 emissions to the atmosphere were 555 ± 85 PgC (1 PgC = 10^15 gC) between 1750 and 2011. Of this amount, fossil fuel combustion and cement production contributed 375 ± 30
        PgC and land use change (including deforestation, afforestation and reforestation) contributed 180 ± 80 PgC. {6.3.1, Table 6.1}
        With a very high level of confidence1, the increase in CO2 emissions from fossil fuel burning and those arising from land use change are the dominant cause of the observed increase in atmospheric CO2 concentration. About half of the emissions remained in the atmosphere (240 ± 10 PgC) since 1750. The rest was removed from the atmosphere by sinks and stored in the natural carbon cycle reservoirs. The ocean reservoir stored 155 ± 30 PgC. Vegetation
        biomass and soils not affected by land use change stored 160 ± 90 PgC. {6.1, 6.3, 6.3.2.3, Table 6.1, Figure 6.8}”

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      2. Thanks. That’s about 30-40ppm of missing data. Not sure how it will affect the curve, but it might make it work. It’s at least a big part of the puzzle I was overlooking (30-40%).

        How come there’s no allowance for CO2 contributed from temperature rise feedback?

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      4. That’s great! The recent numbers, i.e., from 1750 to 1900 show a rapid increase, right into the range I needed for 1900 of near ~300ppm. Adding in the other sources between 1900 and 1959 should ease the reconciliation. Either way, it’s taking out a lot of the guesswork. Great source—thanks!

        As for the temp-rise CO2 feedback, there’s a 100ppm gain over about a 5C temperature rise between glacial min and glacial max — so, that’s about 15-20ppm to be expected over a rise of .85C, right?

        With all this extra info re CO2 levels and emissions, the model will now be able to better constrain the decay profile and won’t be straining for a fit.

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      5. As for the temp-rise CO2 feedback, there’s a 100ppm gain over about a 5C temperature rise between glacial min and glacial max

        Right.

        — so, that’s about 15-20ppm to be expected over a rise of .85C, right?

        I would be careful about that. There’s the time factor, first, as you’re comparing to a period where conditions equilibrated over millennia. And there could be threshold-like factors in there— I don’t know.

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      6. I wrote:
        “As for the temp-rise CO2 feedback, there’s a 100ppm gain over about a 5C temperature rise between glacial min and glacial max — so, that’s about 15-20ppm to be expected over a rise of .85C, right?”

        Although, CO2 gain in the ocean may completely counterbalance that effect or even put it into reverse.

        Like

      7. sj wrote:
        I would be careful about that. There’s the time factor, first, as you’re comparing to a period where conditions equilibrated over millennia. And there could be threshold-like factors in there— I don’t know.

        Duly noted. Thanks again.

        Like

      9. sj wrote:
        I would be careful about that. There’s the time factor, first, as you’re comparing to a period where conditions equilibrated over millennia. And there could be threshold-like factors in there— I don’t know.

        I think a lot of that CO2 feedback is just the rise in ocean temperature. When Hansen speaks about this, that’s how he reduces the issue, although I know there’s a lot of research into other mechanisms.

        In our case, i.e., in the case of CO2-driven warming, It’s probably more CO2 release that didn’t happen but would have if it was solar-initiated warming. In other words, it affects the equilibrium point of air/ocean CO2, but does not contribute to the input budget.

        Like

      10. Going back over the IPCC numbers for CO2 contributors, it’s starting to clarify:

        Fossil fuels emitted are 375Gt with a very small margin of error, i.e., ±30, which is less than 10%.
        Change in land use, incl. deforestation, etc. is 180 with almost a 100% margin of error. If you take the mean numbers for emission and reabsorption, you get 180 – 160 = 20Gt. This is less than 10% of the FF portion, i.e., 375 -155 = 220.

        This jibes pretty well with what I’ve been seeing in the literature and also Hansen’s willingness to ignore it in the glacial scenarios he’s used for calculating ECS. Probably the fact that the error margin in his ECS calculation is huge contributes to his stance.

        An additional confirmation is that the decay profile used by models are pretty close to the one I’ve been using. If there was a whole lot more CO2 to account for, the decay profile would have to be that much more aggressive to match outputs with historical data.

        Thanks for the data—very helpful.

        Like

  12. This is really good:

    Youtube: Meeting the Renewable Energy Challenge: James Hansen Keynote

    29 minutes
    Published on Oct 24, 2014

    James Hansen presents his keynote “Climate Change & Energy: A Global Perspective” at the UI Public Policy Center’s “Meeting the Renewable Energy Challenge” symposium on October 16th, 2014.

    Hansen spends a good bit of time on nuclear, making points about health effects vs fossil fuels and other sources of energy. One major point he makes is one that he has made in the past but I don’t think I’ve mentioned here, is that China and India, where nuclear is most needed, are being denied the best and latest innovations in nuclear technology, which are owned and were developed here in United States laboratories. This is really sad. Hansen is an optimist, but he makes next-gen nuclear sound really appealing. The US is a mixed blessing with what it could potentially do, but right now it is an unmitigated curse.

    None of this stuff is new from Hansen, but it’s usually not the main substance of the lecture.

    Other notes:
    Kyoto was an utter failure. Growth of fossil fuels has gone from 1.5% per year to 3%. LOL
    Scaled implementation of a Fee & Dividend Carbon Tax would reduce carbon emissions by 50% over a period of 20 years and would INCREASE global GDP. LOL, LOL!!
    2C IS A JOKE!!

    A couple of good graphics:

    Sweden has used nuclear and hydro to reduce their carbon intensity to 25%. ALL their electric is non-carbon. Their only carbon contributors are vehicles, and this is not a problem because liquid fuels can be made from electricity.


    I like this graph because it highlights the historical use of coal and wood/biofuels (cow dung, etc).

    Like

    1. Also… this is the first time I’ve heard him mention that we need to reduce world population.

      Like

  13. Joe Romm has an article (Nov, 2014) about a new carbon fee/dividend bill that has been introduced into the US senate. It would begin the fee at $42/ton and increase 2%/year thereafter. Some of the commenters think it should start lower and increase faster, which seems intuitively logical to me. As one commenter said, get the framework in place. Less resistance, less shock to the system.

    The ThinkProgress/Climate site is well structured and implemented from the technical end. Lets you find what you want to read quickly and easily. Romm has an amazing amount of coverage of climate and environment issues. I never really bothered checking out his site because I thought he was one of those quasi-deniers. LOL But, then, lately, I found myself referencing a bunch of his articles because of the good reporting.

    Like

  14. Came across a few good graphics.
    University of Washington Atmospheric Sciences Dept. has some of their curriculum on line and this is a slideshow from a 2004 lecture on climate change. Seems like the science was pretty well defined by then because I don’t see much that has changed. This slideshow does a surprisingly good job of summing up in a few pictures.

    Two slides frame quantitative warming calculations. This one

    shows how long it takes for the 3 main heat reservoirs to heat up. Air comes up to temperature in a few days. But you don’t get the full heating effect until a few centuries have passed. Water in the form of the oceans acts as a buffer, regulating the rate at which the atmosphere can realistically heat up. Any heat gained by the atmosphere is efficiently transferred to the oceans. I think atmospheric water is probably an important intermediary in this buffering system, since it holds, carries and distributes a lot of heat through evaporation, cloud formation and storms.

    But even if there was no interchange between air and sea, you still wouldn’t get the full atmospheric response until the sea had reached equilibrium temperature. This is because the sea surface radiates heat, so it is like a second burner. You have the CO2 effect, re-radiating heat, like the upper burner in a stove. But the sea is the lower burner, and you’re not going to get the full effect until they are both up to temp. /Speculative editorialization

    So, the sea as buffer is one of two main types of delayed heating effect. The other is in this slide: http://oi60.tinypic.com/288wgfm.jpg
    which shows how feedback strength influences temperature response. Pure radiative forcing hides very little uncertainty — mostly just the timing of effect related to the inertia of the reservoirs (air, surface sea and deep sea). (Hansen notes that land effects are also an important factor in response time.) But there is lots of variation of opinion over the magnitude and timing of feedbacks like albedo and secondary CO2 release.

    Together, the two preceding slides are a close rehash of Hansen’s 1985 paper on the timing of climate response to CO2 rise.

    This slide shows how much of Florida goes under water with 1 meter of sea level rise, expected this century (some say 2 meters is possible):

    That’s not too far off, folks. You may want to think twice about selling that boat.

    And Florida is not the only coastal state:

    Almost half the US population lives in coastal areas. Hansen says this is a result of the long period during which sea level has been stable. A large part of the Holocene. 6000 years. This allowed for long-term coastal settlements where people could eat lots of fish and thrive. Civilization. Not so much anymore, as fisheries are collapsing from industrial fishing methods. Sylvia Earle says don’t eat fish.

    Florida underwater is locked in, now that Antarctica is destabilized. It’s a matter of when, not if, and the timing depends on how well we do cutting emissions. I saw this opinion in a video recently—I think it was a Ken Caldeira video. He seems like a sincere scientist, except for the collaboration with Ricke. Very odd. He was even a guest article writer on the Romm blog a few years ago.

    I also came across this IPCC graphic
    http://www.ipcc.ch/ipccreports/tar/wg1/fig9-1.htm
    which demonstrates the concepts of transient and equilibrium warming. At a moderate rate of CO2 introduction, i.e. sufficient to elevate atmospheric concentrations at the net rate of 1% per year (net means CO2 emitted minus CO2 reabsorbed into, primarily, the ocean, so net means measured CO2 in the atmosphere, i.e., ice cores, Mauna Loa, etc.) Air temp rises quickly as long as CO2 is increasing, then the pace moderates when CO2 stops rising and sea temps come along more slowly, buffering air temps.

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    1. He seems like a sincere scientist, except for the collaboration with Ricke. Very odd.

      What the hell?

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      1. Go ahead and tell me why this is an absurd statement. I’m still waiting.

        You’ll have to wait for my full thesis defense as I’m still working on it. But please do note, I’m not the only one with that initial reaction, and nothing you’ve said so far has swayed me.

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      2. I can only shake my head in bafflement.

        Even if you were right that there is something elementary and fundamental wrong with the paper (which you’re not), why would you attack their integrity? Why do you feel the need to go there? How can you possibly think you have the footing to make that accusation? Please don’t disagree the McPherson way.

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      3. I don’t know Scott. Maybe if this was just science I would just make a scientific response. But it’s the survival of the planet. It’s science as propaganda. It’s war. It just seems natural to respond like that. How many times did Caldeira tweet about their new paper? Is that science? I’m not a twitterer, so maybe that ‘s common there.

        It’s also not just the one paper. It’s Caldeira using a video to reverse his earlier opinion that it takes 40 years for the full response to a CO2 input. And it’s the Ricke video advising policy makers to discount public perception of climate change. Public perception is, FINALLY, the one thing that can possibly move policy. But she says, let’s slow down here. I don’t know, Scott.

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      4. It’s science as propaganda. It’s war.

        Take it down a notch. It’s a published piece of research.

        How many times did Caldeira tweet about their new paper? Is that science? I’m not a twitterer, so maybe that ‘s common there.

        That’s called science outreach.

        It’s Caldeira using a video to reverse his earlier opinion that it takes 40 years for the full response to a CO2 input.

        So you’re mad that he described the paper in a video? (Which is something that journal encourages.)

        And it’s the Ricke video advising policy makers to discount public perception of climate change. Public perception is, FINALLY, the one thing that can possibly move policy.

        I don’t remember this or understand your point.

        But she says, let’s slow down here.

        What?? I’m quite certain that your dogged opposition of this paper comes from what you feel it implies about dealing with climate change. If you think it implies we don’t have to work as hard, I think you’ve gotten confused. Certainly, the only policy implication mentioned by Ricke or Caldeira is that this makes it easier to sell emissions reductions, because the benefits are realized sooner.

        Like

      5. And tell me what it was that Schmidt was attacking of Wadhams’? Was it his intelligence or his integrity? And how much attention was paid to the scientific content? I’ve begged for analytic explanation and got rhetoric or no response.

        Like

      7. I wrote:
        And it’s the Ricke video advising policy makers to discount public perception of climate change. Public perception is, FINALLY, the one thing that can possibly move policy.

        sj wrote:
        I don’t remember this or understand your point.

        I posted the video here. If you can untangle the Kissingerese, it’s as I described.

        I wrote:
        But she says, let’s slow down here.

        sj wrote:
        What??

        Yes, that is what she is saying. Please interpret it otherwise.

        I wrote:
        It’s science as propaganda. It’s war.

        sj wrote:
        Take it down a notch. It’s a published piece of research.

        No. It’s the end of the world for billions of people.

        sj wrote:
        Certainly, the only policy implication mentioned by Ricke or Caldeira is that this makes it easier to sell emissions reductions, because the benefits are realized sooner.

        Are you sure that’s how it will be used? If a scientist tells you we’ve got a lot of heating in the pipeline, it’s depressing. Shit’s gonna happen and there’s nothing you can do about it, so the situation is that much grimmer. But if he tells you, instead of 40, 50, 60 or 90 years of backlog, it’s only 10, that’s a huge load off. How do you know how the paper is going to be sold to policy makers?

        OH NO, I WAS WRONG ABOUT THAT 40 YEARS I TAKE THAT BACK IT’S ONLY 10 RELAX!.
        End quote.

        sj wrote (regarding the Schmidt attack):
        We’ve been all through this and I’m not doing it again. Your imagination has run wild.

        Schmidt was, OK let’s take a consensus, how many here think Wadhams is a buffoon? You were, “Oh, well, scientists talk like that sometimes—it’s not all this robotic reporting, etc…”

        I have no idea what kind of satisfactory agreement on the topic you think we came to. It simply faded away until you decided my actions re R-C are beyond the pale. And now it (Schmidt-Wadhams) is supposed to be off bounds.

        Now, here, with the R-C paper, I’m saying this is suspicious, can we look at this and figure out what they’re saying? I’m spending weeks working on the science and working towards a clear explanation.

        What is absurd is denying that there are deniers and that there’s a war going on.

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      8. Are you sure that’s how it will be used?

        I don’t give one shit. If a politician wants to lie about or misrepresent a study, that tells me absolutely nothing whatsoever about the quality of the research or the integrity of the researcher. Should research on natural climate oscillations not be done, or be hidden, or is it wrong, or are those researchers liars just because some politician will reference it in an ignorant argument??

        OH NO, I WAS WRONG ABOUT THAT 40 YEARS I TAKE THAT BACK IT’S ONLY 10 RELAX!.
        End quote.

        It’s a little awkward that I have to ask this… but you do know what “quote” means, right?
        Your contention that changing the answer from 40 years to 10 years = “relax!” is bizarre and wrong. Either you still don’t understand the paper, or you’ve emotionally twisted yourself up in something you can’t untwist from.

        Schmidt was, OK let’s take a consensus, how many here think Wadhams is a buffoon?

        You’re going to stop making things up like this if you want to continue posting here. I don’t even know what real-life event you think this corresponds to.

        Now, here, with the R-C paper, I’m saying this is suspicious, can we look at this and figure out what they’re saying? I’m spending weeks working on the science and working towards a clear explanation.

        That’s great. Stick to trying to understand the science, and cool it on accusing scientists of dishonesty because you don’t understand their work.

        Like

      9. I wrote:
        Schmidt was, OK let’s take a consensus, how many here think Wadhams is a buffoon?

        sj wrote:
        You’re going to stop making things up like this if you want to continue posting here. I don’t even know what real-life event you think this corresponds to.

        After you made such a big deal about the peanut gallery consensus confirming Schmidt’s judgment regarding Wadhams, it’s pretty safe to assume that was an anticipated and intended response, even if it wasn’t explicitly solicited. Splitting hairs. Have you heard that twitter is a social tool? Does it make sense that typical social behavior is to be expected?

        It was strange how people were consoling Schmidt as if he was the one who was attacked. What was that all about?

        I wrote:
        Are you sure that’s how it will be used?

        sj wrote:
        I don’t give one shit.

        Then why did you make the point? Obviously it matters how research is done and presented, otherwise the denier industry wouldn’t spend millions if not billions in the propaganda war.

        sj wrote:
        Should research on natural climate oscillations not be done, or be hidden, or is it wrong, or are those researchers liars just because some politician will reference it in an ignorant argument??

        You can’t separate natural variability from the science of change. That’s what it’s all about. But my ears prick up when I hear “natural variability” in the title of a paper or video. All this work that’s been done to show how warming relates to climate events, the stonewalling of policy by lawmakers for decades, and you really want to encourage policy makers to question the late arriving public perception? Why?

        sj wrote:
        It’s a little awkward that I have to ask this… but you do know what “quote” means, right?
        Your contention that changing the answer from 40 years to 10 years = “relax!” is bizarre and wrong. Either you still don’t understand the paper, or you’ve emotionally twisted yourself up in something you can’t untwist from.

        You seem to think your claim is its own proof because you state it with emphatic words, gaudy metaphor and cutty irony.

        sj wrote:
        That’s great. Stick to trying to understand the science, and cool it on accusing scientists of dishonesty because you don’t understand their work.

        You might wanna see how that shoe fits on your own foot.

        Like

      10. You really need to take a step back.

        Schmidt was, OK let’s take a consensus, how many here think Wadhams is a buffoon?
        After you made such a big deal about the peanut gallery consensus confirming Schmidt’s judgment regarding Wadhams, it’s pretty safe to assume that was an anticipated and intended response, even if it wasn’t explicitly solicited. Splitting hairs.

        First, I didn’t make a big deal of it. I thought it was an interesting window.
        Second, it wasn’t about Wadhams. It was an informal poll of summer sea-ice free date.
        Third, Schmidt had nothing to do with it. He didn’t tweet it, and I don’t know who initiated it- a section organizer or someone giving a talk? It wasn’t his talk, I know that.

        …you really want to encourage policy makers to question the late arriving public perception? Why?

        You’re talking about a different paper here, and you completely misunderstand that one, as well. Stop trying to hastily twist things to your narrative so you can keep your condemnation train rolling, and just TRY TO UNDERSTAND WHAT IS BEING SAID. What you’re claiming bears no relationship to the study.

        You might wanna see how that shoe fits on your own foot.

        Have I woken up in bizarro world?? Is someone playing a prank on me?? Are there hidden cameras behind me??

        I don’t want to keep spending my time on your wild accusations born from motivated misinterpretation. The next time you fly off the handle I’m going to ask you to stop posting here.

        Like

  15. A response by Gavin on RealClimate perhaps casts a different light on the Ricke and Caldeira study:

    This study includes carbon cycle modelling and is thus estimating sensitivity to emissions of CO2. In contrast, TCR and ECS are sensitivity to changes in concentrations. There is no contradiction here because the concentrations in the new study start high and then decline, compared to TCR (1%/yr increasing concentration) or ECS (permanent 2xCO2 concentration).

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    1. That’s what I’ve been trying to explain for a while here. Ricke & Caldeira emitted a pulse of CO2 and then ceased all human emissions, letting the atmospheric concentration respond as it will. ECS scenarios involve sudden increases in concentration that are then held constant. TCR involves increasing concentration 1% each year.

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      2. Oh, no worries- sometimes a different wording clicks. I was just reiterating for anyone else following along…

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    2. A sudden or instantaneous change in CO2 concentration is not required for an ECS scenario. The IPCC graphic I posted earlier illustrates both TCR and ECS using the 1%/year increase as the originating condition. Holding CO2 levels constant thereafter, long enough for ocean heat to equilibrate with forcing is the definitive condition for calculating ECS or observing it in a model.

      Nitpick you could say, but for the context of the Ricke-Caldeira paper, it’s important because the magnitude of the CO2 change relative to the pre-existing level of CO2 makes a big difference for the relationship between the short-term and long-term response. This can be demonstrated by the differences in CO2 response profiles for sudden vs more gradual inputs.

      The transient temperature response will closely follow the CO2 response, since it lags by only about 30 days. I hope to be able to show this in my model but it will take some time to integrate.

      Like

  16. On the sea ice forums, the discussion brought up someone named Ian Eisenman, and his work on the stability of sea ice. I couldn’t find any links to even a summary of his work, but one of the posters speculated, based on his work, that after ice-free summers become a regular phenomena in the Arctic, an abrupt shift to a perennial ice free state might occur, due to “autumn water vapour from open ocean form[ing] a cloud base that severely limits winter ice growth.”

    I seem to remember, in one of these threads, you mentioning that your wife studied ice (apologies if I’ve got that wrong; there’s quite a backlog to go through), so I was hoping that you could find out if this sounded like a fair assessment.

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      1. Aha.

        My understanding (aka guess) on that feeback is that clouds keep end-of-summer heat from radiating back out to space. That right? And that it only matters if the clouds are at a certain elevation?

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      3. That’s a different author, but yeah, seems to be the same idea. Is this kind of thing (increasing humidity, cloud growth) something models can simulate fairly accurately?

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      4. Yes and no. I think water vapor is pretty straight-forward, but cloud changes are the largest source of uncertainty in the projections. It depends on altitude and location, though, and I don’t know how they feel about the Arctic.

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  18. After reading something on SkS, I realized that I had no idea what the difference between temperature and heat content was, so I looked it up (temp = average energy of molecular motion in substance, heat = the total energy?)

    That led me to a question. I’ve seen a few write-ups discuss how, despite the slow-down in the rate of surface temp increase, the heat content of the oceans has increased dramatically in the past decade or so. And my understanding of an El Nino event is that it involves the warmth from all that warm water in the Pacific radiating up to the surface. When/if an El Nino of appreciable size hits, would the transfer of energy cause the oceans’ heat content to fall off in any appreciable way?

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      1. Any new questions I have I’ll post to the new thread, but to wrap this up – when the day comes that the oceans give up heat to the atmosphere, would the years immediately following see the oceans’ ability to soak up heat and serve as a buffer be improved?

        Like

      2. I don’t think so. The ocean’s ability to absorb radiation doesn’t depend on temperature. It’s just a question of how much is being moved to the atmosphere via the surface at any given time.

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