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Comments 11501 to 11550:

11501. One Planet Only Forever at 14:30 PM on 23 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       Eclectic @32,

       When pointing out that the next glacial phase is due in about 20,000 to 30,000 years it could be helpful to add "Easy to get fossil fuels that have been discovered and left in the ground could be burned nearer that time to help human civilization get through that event".

       By then climate science may have developed understanding leading to better ways of dealing with that event. But it would still be 'helpful to future generations' if lots of easy to get fossil fuels were found and left in the ground for a future 'true emergency (energy warming, or other helpful puprose)' rather than harming the future generations by rapidly burning them up now.

11502. Eclectic at 12:05 PM on 23 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       ThinkingMan , it's always worthwhile to step back occasionally and look at the bigger context.

       Global surface temperature had been at a fairly flat plateau for (roughly) 5,000 years of the Holocene Maximum ~ which has been followed by (roughly) 5 or 6,000 years of gradual decline (related to the Milankovitch cycle of insolation).   Owing to the present relatively-low ellipticity of the Earth's orbit, the next glacial phase is due in 20-30,000 years ~ and may be skipped altogether since the oceans are being unusually warmed by AGW.

       The Little Ice Age, the Medieval Warm Period, the Roman Warm Period etcetera are only tiny wiggles in comparison to the multi-millennial decline in temperature.

       Against this long-term decline, you can see the last (roughly) 100 years demonstrates a temperature rise which is shooting upwards like a rocket.   And is now surpassing the Holocene Maximum.   IMO it is beyond ridiculous for denialists to assert that our modern-day global warming is the result of a 60-year oscillation in oceanic currents.

       Yet that is what some of the (more intelligent) denialists assert.   No need to waste your time reading Professor Curry's blog ~ she is still suggesting that "up to" 60% of modern warming could be caused by confluence of oceanic current cycles.   Quite marvellous it is, how a giant dose of "Motivated Reasoning" can so completely distort the rational thinking of an educated intelligent person.

       You see rather similar bizarre thinking coming from Lindzen & Spencer & others.   (And much of the remainder of denialists are still loudly proclaiming that CO2 has zero or negligible Greenhouse effect.)

11503. scaddenp at 08:36 AM on 23 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       thinkingman - I appreciate your question. It is always good to clarify so we dont talk past each other. It is also worth clarifying "cooling".

       By "natural cooling forces" I understand you to mean things that would affect the temperature trend as opposed to year by year or even decadal average variation. On scale of 3-10 years, then the natural, chaotic, ENSO cycle is dominant. The upper ocean exchanges heat with atmosphere. A series of La Nina can look like cooling; a series of El Nino can look like warming. However on climatic scales (or even scales of decade), these do not affect the temperature trend. I mention this because you asked "since 1998" which immediately rings alarm bells. A lot of pseudo-skeptic arguments are based on cherry picking a big El nino event and then comparing trend after that. You can expect "since 2016" to become popular on certain websites.

       Assuming you mean temperature trend and actual forcing, I can be more definitive. You could say that AGW is countering some external forcings. The Milankovich cycle has been slowly cooling for some time, though the effect is so slow that its impact on climate even over a century would be hard to determine. You could also argue that total solar irradience trends since 1990s has been slightly negative. The change in forcing again is incredibly minor comparied to measured AGW-driven changes in surface radiation. I dont see volcanic aerosols having any particular trend.

       I do not see any convincing evidence for some magical 60 year/80 year cycles, especially when proponents struggle to identify a physical source.

11504. MA Rodger at 05:33 AM on 23 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       ThinkingMan @26,

       You point not to a "paper" but to a 2015 blog and its author is somebody called Vaughan Pratt. It is only posted by Judy Curry on her blog-site.

       Even so, it is full of enough nonsense to match that of Curry. The initial assertion (from Curry) that:-

       "About 40% of the warming since 1880 occurred prior to 1950, and is not attributed to human greenhouse gas emissions."

       and (from Pratt) that:-

       "The importance of this period (ie late 19th century to 1950) is that it contains by far the best data we have about natural variability in the absence of significant variation in CO2."

       This is pure nonsense. Examine IPCC AR5 Table AII.1.2 and you find that a third of the CO2 forcing to 2011 and almost the same proportion of 'GHG Other*' to 2011 were present by 1950. Curry's grand climate wobble is based solely on a dip and a peak in the global average temperature record. This is not insignificant & Curry is plainly wrong to suggest it is. Her grand wobble theory has no basis other than that. It is no more than curve-fitting and has no serious evidential support.

11505. ThinkingMan at 23:49 PM on 22 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       scaddenp:  Do you accept or reject the possibility AGW offset natural cooling forces from 1998 to the present?  And, are those specific cooling forces adequately reflected in the CMIP5 ensemble mean?   Your position is not clear in your two recent posts.

11506. TVC15 at 18:52 PM on 22 March 2019
       Climate's changed before
       

       I give much thanks to all that have helped me broaden my knowledge of global warming and especially how to deal with the denialist I've been debating for almost a year. I've not quite dealt with a denialist as the one I've presented. I agree with you MA Rodger! This denialist is as an exuberant fool relishing the chase. He is not worth a bean.

       Special thanks to Michael for the link to HHoffman et al 2017.

11507. scaddenp at 09:08 AM on 22 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       The blog post happily assumes variation from the trendline is "natural variability". Huh?

       

       Above the climate forcing used by models. Volcanoes are of course natural variability but it would be a mistake to regard the variability as unforced change. Furthermore, the effect of man-made aerosols (ie pollution) 1940-1960 remain hard to tie down.

11508. scaddenp at 07:13 AM on 22 March 2019
       Climate's changed before
       

       TVC - first thing to remember is the old saying that you cannot reason a person out of position that they were not reasoned into. Deniers will deny. You can however demonstrate to other bystanders that their position is not based on science. You could ask if they could consider that any evidence will change their mind. Chances are the answer is "nothing".

       The CO2 lags argument is already in Skpsci. See here.
       https://skepticalscience.com/co2-lags-temperature.htm and this is really where this discussion belongs. The argument relies on believing you can choose which bits of chemistry and physics apply at will.

       In short, CO2 is both a feedback AND a forcing. Anything that causes temperature to rise will eventually cause CO2 to rise as well (and vice versa) but on timescales of centuries to a thousand years (time for ocean mixing). Our adding CO2 from emissions will eventually cause CO2 to be releassed from natural sinks making matters worse. In ice age cycle, it acts to convert a local event (change in insolation in NH around 65N) into a global event. Locally the milankovich forcing is large. If you look at MA Rodgers graph, the Milankovich forcing changes insolation at 65N by 10+W/m2 between glacial and interglacial. The forcing from doubling CO2 is around 4W/m2. The difference is that change is local for milankovich (I note the deniers examples to "prove" it was global were all NH higher latitudes), but global for CO2. I should say ditto for water vapour but feedback is much faster. Your denier is pulling a strawman argument, claiming CO2 is supposed to explain all climate change. Climate science by comparison claims that all physical laws apply at all times and climate responds to net forcing, not one single factor.

11509. michael sweet at 06:48 AM on 22 March 2019
       Climate's changed before
       

       MA Rodger and others interested:

       I think the full text of HHoffman et al 2017 is here.

11510. nigelj at 05:31 AM on 22 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       "The important outcome is: Rising CO2 levels apparently (and may have indeed) offset natural cooling forces since 1998-2000. This possible outcome supports the AGW case."

       Yes it does.

       The pdo ocean cycle here correlates rather well (by eye) with the bumps and dips in the surface temperature record since 1900, including the so called recent pause. 

11511. TVC15 at 04:36 AM on 22 March 2019
       Climate's changed before
       

       MA Rodger, thank you so much! I am not a climate scientist but I do hold 3 science degrees in the field of medical science. I love this site as it has helped me learn so much about areas of climate change that I was unaware of.

       This denier posts walls of misinformation and rants just as you have read and since most people in the world are not well versed in science, they think he sounds great and knowledgeable. It's astounding the things he's says. He tried arguing CO2 is a dissolved and released gas in seawater, and that it's based on Boyle's Law. I was astounded and knew immediately I was dealing with a layman attempting to come off as being knowledgeable in science.

       I often wonder where he gets his misinformation from.

       He is constantly trying to push these concepts:

       My position is that CO2 levels are irrelevant. CO2 levels are a lagging indicator. Temperatures increase, then CO2 levels rise. Temperatures decrease, then CO2 levels drop.

       There are many articles that all say the same thing.

       What were CO2 levels during the last Inter-Glacial?

       EPICA Ice Core data for the last Inter-Glacial period shows CO2 levels never rose above 286.8 ppm CO2 (peak at 128,609 years before present).

       Because CO2 levels peaked at 286.8 ppm CO2 and temperatures in Greenland were 14.4°F warmer than present and on the opposite side of Earth temperatures were 22.5°F warmer than present, you cannot claim CO2 drives the climate.

       In fact, that refutes global warming.

       Here we show that the south GIS was drastically smaller during MIS 11 than it is now, with only a small residual ice dome over southernmost Greenland.

       https://www.nature.com/articles/nature13456

       If we go back to MIS 11, we find CO2 levels peaked at 283.5 ppm CO2 at 411,071 years before present.

       If you look through EPICA Ice Core Data, CO2 levels never peaked more than 292 ppm CO2 over the last 800,000 years.

       Prove, with absolute certainty, that if CO2 levels were back down to 287 ppm, temperatures in Greenland would not rise another 14.4°F and temperatures in Siberia would not rise another 22.5°F.

       If you are unwilling to do that or cannot do that, then you have proven global warming to be a fatally flawed theory.

       Given that CO2 levels are currently in excess of 400 ppm CO2, why haven't temperatures risen?

       You say they have? Yeah, 1.4°F over 140 years, but, I've already proven that temperature fluctuations of 20°F in a matter of years is not unprecedented.

       I think Skeptical Science should add this denier’s myth claims to the most used climate myths. This denier makes some of the strangest claims and draws odd conclusion’s based on what appears to be cherry picking and lack of basice science understanding.

11512. MA Rodger at 23:36 PM on 21 March 2019
       Climate's changed before
       

       TVC15 @645,

       Picking up on the denialist's assertion that his position would be supported by "any peer-reviewed paper," I have been unable to find the full text of Hoffman et al (2017) 'Regional and global sea-surface temperatures during the last interglaciation'  (which is of course one such paper) but its abstract (below) doesn't give any room for the denialist's bold assertions about blindingly hot Eemian global average temperatures which @642 the denialist describes as "15.3°F warmer than now" or +8.5ºC relative to today.

       "The last interglaciation (LIG, 129 to 116 thousand years ago) was the most recent time in Earth’s history when global mean sea level was substantially higher than it is at present. However, reconstructions of LIG global temperature remain uncertain, with estimates ranging from no significant difference to nearly 2°C warmer than present-day temperatures. Here we use a network of sea-surface temperature (SST) records to reconstruct spatiotemporal variability in regional and global SSTs during the LIG. Our results indicate that peak LIG global mean annual SSTs were 0.5 ± 0.3°C warmer than the climatological mean from 1870 to 1889 and indistinguishable from the 1995 to 2014 mean. LIG warming in the extratropical latitudes occurred in response to boreal insolation and the bipolar seesaw, whereas tropical SSTs were slightly cooler than the 1870 to 1889 mean in response to reduced mean annual insolation." [My bold]

11513. ThinkingMan at 22:50 PM on 21 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       Scaddenp:  Will reply at another time.

       All:  Parts of this article are relevant to the concept.  https://judithcurry.com/2015/11/03/natural-climate-variability-during-1880-1950-a-response-to-shaun-lovejoy/

       Yes, I know Judith Curry's name will cause some followers of this blog to recoil.  Pls read the paper, nevertheless.

       The 2nd & 4th graphs are pointed out because a picture is worth1000 words.  The 4th graph shows that since 1950, rising atmospheric CO2 levels explain well a long term temperature trend.  The 2nd graph shows the difference between recorded temperatures and temperatures consistent with contemporaneous CO2 levels.  The difference is attributed to "natural variability".  Pls note the downward trend in natural variability from 2000-2012.  Whether the downward trend is caused by a cycle or natural events with unpredictable timing is a side issue.  The important outcome is:  Rising CO2 levels apparently (and may have indeed) offset natural cooling forces since 1998-2000.  This possible outcome supports the AGW case.

11514. MA Rodger at 18:20 PM on 21 March 2019
       Climate's changed before
       

       TVC15 @645,

       The denialist appears to me as an exuberant fool relishing the chase. He is not worth a bean.

       On the source of his numbers - You could ask him if it is that he cannot remember where these numbers are allegedly lurking and thus he sets out so many possible sources. Or is he saying there are so many sources that he is spoilt for choice? All we need is one credible reference to be able to judge his preposterous claims on interglacial global average temperatures. Perhaps he should also set Wikipedia straight. They, despite using Antarctic EPICA ice core data unajusted, still have nothing like the temperature record alleged by this denier in their account of the Geological Temperature Record.

       The rest of his rant is basically saying there is interglacial warming yet to appear in the present Holocene interglacial, and this based on the level of deglaciation at the height of the Eemian deglaciation. Perhaps he can set out the mechanism he sees as providing this warming-yet-to-appear.

       In sensible speak, the reason for the Eemian being warmer than the Holocene is down to the reduced glaciation driven by high latitude Northern insolation. It is, of cource, a dynamic system so the timing of this insolation within the ice age cycle is critical. The denialist seems to fail to grasp that timing is everything and is bogged down by considering the duration of any particular swing in the Milankovitch cycles.

       

11515. TVC15 at 15:05 PM on 21 March 2019
       Climate's changed before
       

       Scaddenp and MA Rodger,

       I'm starting to think this denialist is being paid to spread myths and move goal posts.

       When I asked for references I was told that its a "government source, or from Nature, NOAA, National Geographic or any peer-reviewed paper"

       So essentially they could not provide a concrete reference for the nonsense numbers.

       I also looked for a timeline of the last 8 interglacial global temps and could not find a good source.

       Below is a typical argument of a denialist. 

       It's not just Greenland. It's also Baffin Island:

       From applications of both correspondence analysis regression and best modern analogue methodologies, we infer July air temperatures of the last interglacial to have been 4 to 5 °C warmer than present on eastern Baffin Island, which was warmer than any interval within the Holocene.

       Vegetation and climate of the last interglacial on Baffin Island, Arctic Canada

       4°C to 5°C corresponds to 7.2°F to 9.0°F

       And in eastern Siberia:

       Our pollen-based climatic reconstruction suggests a mean temperature of the warmest month (MTWA) range of 9–14.5 °C during the warmest interval of the last interglacial. The reconstruction from plant macrofossils, representing more local environments, reached MTWA values above 12.5 °C in contrast to today's 2.8 °C.

       Continental climate in the East Siberian Arctic during the lastinterglacial: Implications from palaeobotanical records

       12.5°C is 22.5°F warmer.

       So, this is not a regional phenomenon occurring only in Greenland. It's global.

       And, if you've noticed, the climate-nutters refuse to acknowledge the science, because it contradicts their belief system.

       The Milankovitch Cycle has nothing to do with it.

       Originally, Glacial Periods lasted 40,000 to 42,000 years and Inter-Glacial Periods lasted 12,000 to 15,000 years.

       What does that have to do with the Milankovitch Cycle?

       Absolutely nothing.

       Oh, wait a minute, I get it....you're looking at the 40,000 to 42,000 year Glacial Period and thinking it jives with the 41,000 year Cycle, which is just one of three Cycles.

       It should be very obvious, because peak-to-peak, the cycle is 52,000 to 57,000 years.

       I often wonder where these types of minds come from. It's interesting that creationists argue in the same manner. I often wonder how the human mind can allow itself to be completely deluded with self-righteous beliefs.

11516. John Hartz at 09:42 AM on 21 March 2019
       2019 SkS Weekly Climate Change & Global Warming News Roundup #11
       

       citizenschallenge: You conclude your most reponse to me with:

       Moral of the story stop focusing on tiny uncertainties - Redirect the dialogue back to the known certainties - Because they certainly tell us enough!

       Which is exactly why Bernie Sanders shouldn't have said what he did about tornados and climate change.

11517. scaddenp at 07:13 AM on 21 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       Invoking unspecified "natural cycles" does not further understanding. There are certainly natural "cycles" or more likely quasi-periodic variations at work. It is important to distinquish between internal variability (energy moving around in an unevenly heated water-covered planet) and variability in climate forcing (eg milankovich cycles, solar output variation, volcanic aerosols). Internal variability is things like the ENSO cycle which is dominate cause of intra-decadal variability. These are unpredictable, (chaotic) and affect climate largely by heat exchange between ocean and atmosphere. Climate models have no skill in predicting these variations. When you see a graph like:

       

       then the grey area is the space defined by multiple individual model runs. Any observational line within the grey area is compatiable with the model output. If you look at individual runs of the climate models, then you see the many possible outcomes. This post covers what the models are actually telling you. There is no skill expected at decadal predictions, but the model mean does a pretty good job at prediction the 30-year (climate) trends.

       While small amounts of heat transfer from oceans affect temperature, blaming warming on heat coming from the ocean while ocean heat content is increasing is "voodoo economics". If some unknown ocean "cycle" is providing the heat, then how come the ocean is getting hotter?

       

        

       Variation in external forcings is another story. The milankovich forcing is readily calculated and we are warming despite a very slow negative orbital forcing. Solar has quasi-periodic cycles but we can directly measure solar input at top of atmosphere. You cannot claim a solar cause when solar input is flat or declining. Volcanoes of cource are unpredictable but models must put in a "average" changes to aerosol forcings or the models would run too hot. You can always re-run models with actual forcings for solar, volcanic etc and this is done.

11518. MA Rodger at 05:52 AM on 21 March 2019
       Climate's changed before
       

       TVC15 @642,

       What this denialist is saying in proper numbers is that seven previous interglacials had global average tmperatures between 19ºC & 23ºC when present global averages are put at 14.7ºC. So that would put these prior interglacials +4.3ºC to +8.3ºC relative to today.

       There is a graph in the screed below this thread showing none of the past four interglacials topping +4ºC above the 1960-90 average. (Two are a tad above +3ºC and two a tad above +2ºC). But the graphic is unreferenced so not that helpful but indicative that the denialist is talking nonsense. (I have the thought that the graph looks a bit like Vostok ice core data which means it still requires adjusting for polar amplification to provide global temperature.)

       Yet even the EPICA ice core data (which covers back to eight previous interglacials) doesn't manage the '+4.3ºC to +8.3ºC relative to today' for seven prior interglacials. Only five of last eight were warmer than 'today' and the warmest, the Eemian, was +4.8ºC which should be perhaps at least halved to give a global value and account for polar amplification.

       

       One of the problems with identifying a Greenland temperature for the Eemian is that Greenland pretty-much melted out in the Eemian. Yet to see this as a global temperature thing is a step too far. Yes, it would take very little increase in global temperature to set Greenland melting out (something like +1.5ºC above pre-industrial) but the Eemian had a far stronger Milankovitch cycle warming the Arctic which would suffice just as well, even with a lower global average temperature.

       Generally though, the denialist is spouting nonsense numbers. So the questions of import - Where does he get these nonsense numbers? Which nonsense factory?

11519. nigelj at 05:33 AM on 21 March 2019
       2019 SkS Weekly Climate Change & Global Warming News Roundup #11
       

       Citizenchallenge

       I havent followed this issue too much but I gather Climate Feedback "corrected" Bernie Sanders on tornados and did so in a very extensive and fairly hyper critical sort of way.

       I think they probably did this to avoid sceptics and the right wing accusing them of ignoring mistakes and suffering from tribal group think. So climate feedback were trying to be very "proper and objective". I think "warmists" do  need to ensure we don't ignore bad science.

       Unfortunately it kind of distracts from the big issues and undermines Sanders. So I know where you are coming from. Damn frustrating. Climate feedback should have been smarter and kept it short and simple and less hostile towards Sanders "Theres no evidence climate change is making tornados worse yet but several models predict it will cause changes (this is my underdtanding). Details can be found in.." So dont make a big issue of it.

       I think messaging climate science for the masses is very challenging. If its too complicated and nuanced many peoples eyes will glaze over. If its too simple it will bore people with a scientific curiosity. This website does do quite well by having basic and advanced explanations.

       There are no magic answers. Style of communication is going to obviously depend on the audience and must be tailored to fit.

       There is a lot to be said for keeping things simple, especially if media interviews are short. We had a prime minister (sort of a similar role to president) who was a brilliant communciator. He kept the message simple, but with just enough of the critical details to give substance. There was no waffle or generalisations either.

11520. william5331 at 04:43 AM on 21 March 2019
       Editorial cartoonists lampoon, praise Green New Deal
       

       It's just ridiculous.  Greening America energy, repairing her infrastructure, improving health care and so forth would create jobs, increase the tax take, reduce welfare payments and in every way revitalize the sagging economy of the USA.  The benefits would be primarly to the people rather than the uber rich and perhaps this explains all the propoganda against the Green New Deal.  As long as politicians depend on the financing of their next election campaign from the vested interests, even the ones that pay lip service to the idea will never do anything substantial to push it forward.

11521. One Planet Only Forever at 03:48 AM on 21 March 2019
       Humans are greening the planet, but the implications are complicated
       

       jzk,

       This in not 'my website'.

       My understanding is that it is a website developed to improve understanding regarding climate science. Its focus is clearly on counter-acting attempts to diminish the awareness and understanding of the future implications of the unsustainable and damaging developed human activity related to climate science. It does that by overcoming and correcting misleading claim-making.

       I have seen many other comments attempting to claim that information presented on this site is political rather than 'just science'. I question the motives of anyone making such a claim.

       Improving awareness and understanding related to climate science is undeniably being deliberately compromised by people who wish to maintain beliefs that the global burning of fossil fuels is acceptable, does not need to be rapidly curtailed (some even try to claim it is 'helpful' without providing any proof that a net-benefit for future generations is being created). And hinting that increased Greening is occurring and that is a Good Thing is a politically misleading claim-making effort (an effort that could be pursued if the article title had not correctly qualified the incorrect belief in the 'benefit of increased Greening due to increased CO2').

       In addition to the questions raised regarding the greening in the article (the reason its title justifiably includes a 'but'), the undeniable awareness and understanding (science thinking if you wish) is that the greening discussed in the article does not neutralize the global warming climate change impacts of burning fossil fuels. I would argue that that should have been included in the article.

       A related undeniable fact is that any perceptions developed from an unsustainable and harmful activity, like the burning of fossil fuels, are 'unsustainable'. That fact nullifies your attempt to claim that articles describing the negatives of fossil fuel burning should include a 'but' about how beneficial they are (they are not creating a sustainable benefit).

       No part of those two undeniable understandings is 'political', except for the political attempts to deny them.

       A better title may have been "Though increased CO2 can be seen to be increasing plant growth in the past, it would be incorrect to claim that the observed increased plant growth due to increasing CO2 in the atmosphere means that the increase of CO2 due to fossil fuel burning is creating a sustainable improvement for the future of humanity".

       The improvement of awareness and understanding that is required to develop sustainable improvements for the future of humanity (the real value of science), cannot occur without a holistic assessment. And the only positive and negative evaluation that has merit is the 'future positives and negatives'. Evaluating current generation positives with future generations negatives is an undeniable incorrect evaluation. No harm should be done to Others, and the future generations are a massive group of Others (that is not political or scientific, it is the fundamental of ethics and morals that should govern everything humans do).

       As you may now be aware, I replied to your comment the way I did because I personally considered it to be 'politically motivated, rather than scientifically motivated'. Your reply to my reply appears to have confirmed my initial impression.

11522. ThinkingMan at 03:25 AM on 21 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       To all: TY for the informative feedback.

       The point some APPARENT cycles are NOT genuine cycles is valid.

       It is also the case that genuine cycles with differing periodicities can cancel, mute or accentuate their expression.

       The above combined with the many natural forces influencing temperature, climate ... makes validating and explaining cycles a brain busting challenge.

       "Proving" AGW offset natural cooling forces from 1998 to the present will be at least as challenging.   Timing (reasonable start dates for a possible natural cooling phase) is only one feature that prompted me to raise the possibility.  A second is:  The approx. 0.2C/decade rate for AGW is similar to the rates at which temperature trended downwards from 1880 to 1910 and the early 1940s to the mid 1970s.  The dates are approximate.  A third is:  The AGW concept may be valid despite the fact climate models as a group overstated the amount the amount of warming over the past 20 yrs or so.

11523. jzk at 01:48 AM on 21 March 2019
       Humans are greening the planet, but the implications are complicated
       

       One Planet Only Forever,

       The qualifying nature of the article and your post is fine if you are political website looking to advance a postion.  That is not science.  Science has no position.  Potential downsides to increased greening?  That is for another article.  Are there currently downsides to the increased greening?  Are current crops lower in nutritional value than crops from 30 or 40 years ago?  Those are valid scientific questions.  Again, have whatever kind of website you want.  Just be up front about it.  Further, in arriving at any conclusion about a particular course of action, one must honestly evaluate the positves and the negatives.  If you can't do that, then who can take your conclusion seriously?

11524. citizenschallenge at 01:05 AM on 21 March 2019
       2019 SkS Weekly Climate Change & Global Warming News Roundup #11
       

       correction:  Sad. Nothing humorous about it.

11525. One Planet Only Forever at 00:56 AM on 21 March 2019
       Humans are greening the planet, but the implications are complicated
       

       jzk,

       I will open with a Good Reason to 'qualify the greening benefit of increasing CO2". The article includes the following point.

       "About one quarter of the carbon dioxide placed annually into the atmosphere by fossil fuel combustion has been hypothesized to be removed through enhanced vegetation growth and accumulation of organic carbon in land ecosystems."

       That means that increased CO2 from burning fossil fuels is only partially affected by increased plant growth. The greening does not fully neutralize the new CO2 introduced to the recycling environment by burning buried ancient hydrocarbons. As a result, climate change impacts of the warming that are harmful to future generations and difficult for them to adapt will happen (is happening) in spite of the greening.

       The article also included points about the potential that the added greening may not be helpful for humans.

       I will close with a comment regarding "..."but fossil fuel provides needed electricity for the world's poor" or any other benefit."

       Any developed perceptions of benefit from a harmful and unsustainable activity like the burning of fossil fuels is undeniably unsustainable into the future, and harmful to the future. So, the continuation of attempts by people to personally benefit from burning fossil fuels can be argued to be creating a larger future correction that will require very significant corrections of developed perceptions of status and corrections of perceptions of what is Helpful.

       We already see the reality of that understanding. The lack of responsible actions by the supposed leaders of the planet through the past 30 years has created more future harm, and has created a requirement for a more dramatic correction of what has developed irder to responsibly limit the harm done to the future of humanity.

11526. citizenschallenge at 00:54 AM on 21 March 2019
       2019 SkS Weekly Climate Change & Global Warming News Roundup #11
       

       John:  This isn't about the minutia of scientific consensus !

       This is about explaining what science knows to unscientific people - this is not about the inner workings or arguments amongst scientific community. Why won’t you acknowledge that importance distinction?

       Shouldn't we be Communicating WHAT IS KNOWN - and creating a clarifying dialogue that converts our global climate engine from some untouchable abstract notion to something tangible, that carries some visceral enlightenment that leads to a real sense of awareness.

       ClimateFeedback's did not do that. Below the screen shot I took was another explanatory paragraph that crammed nearly 300 words into it. That may work great for serious scientists who are trained to digest copious amounts of written information, but it doesn't work for the rest of us regular mortals.

       John, you conclude that there is no scientific consensus between the man-made climate change and the frequency and intensity of tornados in the US.

       Well than what about the damned consensus that extra heat is accumulating in our climate system? Or the consensus that our current biosphere is custom fitted to our planet's heat budget and that provided radically more energy to the system will be reflected in increasing destructive weather phenomena?  Why not redirect focus?

       Seems to me in real life when we find ourselves in the weeds (so to speak) - the sensible thing is to pull back from our overwhelmingly confused situation and back into territory that we understand. Then we start with what we know for certain and continue forward with that, in light of the new lessons learned.

       What you keep ignoring about my message is: Stop focusing so much on the uncertainties. Don't talk to kindergartners as thought they are thoughtful adults. Come on, look at whom America* gave it's presidency to - that is not the conduct of an introspective thoughtful people. (* not that others are doing much better)

       That's an indication of a people who do things by shallow impulse, swayed by pretty one-liners and gut feeling, rather than digesting substantive words and seeking out information.

       You may be correct that there is no scientific consensus regarding "frequency and intensity" - What I take issue with is advising to toss up our hands in the air - list all the minutia you can think of to prove how thoroughly scientists are investigating this and call it good.  

       Never noticing your crowd is walking away more confused than clarified - that my dear friend is exactly what plays into the hands of climate science denier! Those who created this phony tornado distraction expressly to confuse and waste time, to begin with.

       Now you tell me that's the best we can hope for - and you wonder why I'm disillusioned at the powers that be.

       Considering the Kochs' have been doing all the winning of passionate hearts and minds these past decades, even as the evidence does nothing but become more solid, I find it humorous that you are so entrenched in repeating the same sloganeering that hasn't worked for oh so long.

       Moral of the story stop focusing on tiny uncertainties - Redirect the dialogue back to the known certainties - Because they certainly tell us enough!

11527. jzk at 23:06 PM on 20 March 2019
       Humans are greening the planet, but the implications are complicated
       

       Why do you write "but" in the title?  If there is evidence about the benefits of increased CO2, why not let it stand on its own?  When you cover a topic about the negatives of CO2, do you say "but fossil fuel provides needed electricity for the world's poor" or any other benefit?  Or do you just let that stand on its own?  One way shows bias.  The other way shows science.

11528. Postkey at 20:10 PM on 20 March 2019
       CO2 lags temperature
       

       “Tectonics in the tropics trigger Earth’s ice ages, study finds
       Major tectonic collisions near the equator have caused three ice ages in the last 540 million years. . . .
       Over the last 540 million years, the Earth has weathered three major ice ages — periods during which global temperatures plummeted, producing extensive ice sheets and glaciers that have stretched beyond the polar caps.
       Now scientists at MIT, the University of California at Santa Barbara, and the University of California at Berkeley have identified the likely trigger for these ice ages.
       In a study published today in Science, the team reports that each of the last three major ice ages were preceded by tropical “arc-continent collisions” — tectonic pileups that occurred near the Earth’s equator, in which oceanic plates rode up over continental plates, exposing tens of thousands of kilometers of oceanic rock to a tropical environment.”
       http://news.mit.edu/2019/tectonics-tropics-trigger-ice-ages-0314

11529. Kevin C at 18:02 PM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       Just a quick note: I spent 6 hours doing research based on 1 comment yesterday. I've started on PV's comments, which contain some very useful context which help understand some of RB's paper list.

       I can only devote 1-2 hours a day to this over the next 3 days, but I am hoping to make a further contribution either today or tomorrow.

11530. scaddenp at 11:44 AM on 20 March 2019
       Climate's changed before
       

       Artemsis, the proposition is puzzling and it would help if you could get more information on what informs your denier. Estimating a global mean temperature through the Quarternary is not a simple proposition and it looks to me as if a no. of data sources have been mis-interpreted. The temperature of Greenland at LIG cf present might also be confused about what is "now" (The meaning of 0BP in ice core records). In short, we need the references used by the denier that back the above claims.

       Beyond that there is some sleight-of-hand in the argument. Climate does not change on its own. It changes in response to changes in net forcings and the ice ages are no different. The ice age cycle is due to orbitally-driven changes in the distribution of solar insolation in the northern hemisphere, which are amplified into global change by CO2 and albedo feedbacks. Temperatures in NH polar regions can indeed be warmer in interglacials with lower CO2 because the incoming insolation for that region is much higher than today. This is not a global change however. More importantly, the milankovich forcing is now decreasing. Without our anthropogenic CO2 we should be slowly cooling. It is important to realize however that this change is very slow - milliwatts per century - compared to emission CO2 forcing which is more like 1W per century. Even without our emissions, the next glacial would have been 50k into future. (Berger and Loutre 2002)

11531. nigelj at 10:50 AM on 20 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       MA Rodger @21, thanks. The Scarfetta paper (2010)  claims there exists a 60 yr climate cycle related to motions and gravity of the planets Jupiter and Saturn, and he makes the claim it will cause global cooling from 2000 - 2030. This idea has all been dealt a rather lethal body blow by the last 4 years temperatures, right in the wrong place in his cycle! So yeah fairyland stuff, and spurious correlations perhaps, or just some very weak insignificant relationship.

11532. TVC15 at 10:05 AM on 20 March 2019
       Climate's changed before
       

       Hi Skeptial Science,

       First let me say that I LOVE this site as it's helped me to debunk the human caused climate change deniers.

       I keep running into one denier who keeps repeating this: 

       "The average global temperatures for seven of the previous Inter-Glacial Periods was 66.2°F to 73.7°F not the current 58.4°F and CO2 levels never exceed 292 ppm CO2.

       The temperatures in Greenland during the last Inter-Glacial Period were 14.4°F warmer than now, in part, because the average global temperature was 15.3°F warmer than now, and CO2 levels peaked at 287 ppm CO2.

       So, how can you possibly state with absolute certainty that temperatures will not rise another 7.8°F to 15.3°F on their own?

       The reason it was 14.4°F warmer in Greenland than it is now is because during the last Inter-Glacial Period, the average global temperature was 73.7°F and not the current 58.4°F."

       "You should also know the Greenland Ice Sheet always melts, and the Western Antarctic Ice Sheet always melts, and that sometimes the Eastern Antarctic Ice Sheet undergoes substantial melting, like it did during MIS-5 and MIS-11, and that it may have had substantial melting during other Inter-Glacial Periods, but the data has not yet been evaluated.

       In short, nothing abnormal is happening very slowly."

       How to respond to what appears to be inaccurte cherry picking?

11533. scaddenp at 09:40 AM on 20 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       Scarfetta has tried to relate climate to who knows now how many unphysical cycles. However, the methodology used to detecting them is, well somewhat suspect. This paper does a take-down of the methodology and reanalysis with proper method. Scarfetta replied but another take-down here.

       While the statistical/mathematical analysis is pretty confusing, the real issue is the lack of any credible physical mechanism.

11534. Post Vegan at 09:10 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       One other thing, as noted in my blog entry on methane, Ruminations-Methane math and context, spikes in atmospheric methane emissions correlate with industrialization, conventional natural gas use, and most recently the fractured natural gas industry. From 1998 to 2007, atmospheric methane levels had leveled out. During this period of time, global cattle inventories increased. Since 2007, global cattle inventories have decreased yet atmospheric levels of CH4 have again started to rise. So there is NO correlation between global cattle inventories and atmospheric CH4 levels. What started in 2006? You betchya, fracking. Typical microbial sources of methane (methanogenesis from archae- methanogens) have C12 isotopic signatures of methane while thermogenic sources of methane (fossil fuels) have C13 isotropic signatures of methane. But fracking and coal bed gas also have C12 isotopic signatures. This has led to some confusion in top down analysis of methane sources, especially when very rudimentary inventories of CH4 isotopes have been used. There's a lot of overlap in signatures, but in general some studies have been attributing CH4 to the animal Ag sector that should really be attributed to the natural gas fracking sector. (Note bottom up analysis of CH4 tends to over count and place blame on those sources of methane easier to extrapolate - like cattle- rather than sources of methane harder to account for like leaky gas pipes or the number of cockroaches).

11535. RedBaron at 09:06 AM on 20 March 2019
       New rebuttal to the myth 'Holistic Management can reverse Climate Change'
       

       @22 nigelj,

       The reason for the dichotomy in numbers is for 2 reasons. 

       1. The second pathway (LCP) was completely unknown until very recently. Glomalin wasn't even discovered until 1996 and it wasn't until several years after that when we began to understand its importance. Much of the literature simply omits it completely and much of the soils test data doesn't even sample deep enough to detect carbon sequestered that way.
       2. NPK fertilizers shut down AMF symbiosis. So even if it is known, there is a tendancy to believe it doesn't matter anyway because chemical fertilizers are required to keep yields up. This is wrong of course. Fertilizers are not required to keep yields up, if the LCP is fully functioning.  This is not known by very many people though.
11536. MA Rodger at 06:50 AM on 20 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       nigelj @20,

       The title? It is that the author is away with the fairies that "does not inspire me with confidence." The PDF below should work. Enjoy!!

       And that mention of "many ancient calendars" referenced in Wikithing appears as the un-referenced quote:-

       "A quasi-60 year cycle has been found in numerous multi-secular climatic records, and it is even present in the traditional Chinese, Tibetan and Tamil calendars, which are arranged in major 60-year cycles."

       Scarfetta N. (2010) 'Empirical evidence for a celestial origin of the climate oscillations and its implications.'

11537. nigelj at 06:11 AM on 20 March 2019
       The temperature evolution after 2016 suggests hotter future
       

       "Climate oscillation" on wikipedia lists various relevant cycles. The AMO is around 60 years. The Gleissberg cycle is a weak solar cycle of about 88 years.

       Of interest is the statement "a 60-year climate cycle recorded in many ancient calendars[1]" This in turn is linked to a paper by Scarfetta . "Empirical evidence for a celestial origin of the climate oscillations", but the link to this paper wouldn't open when I tried it. The title of the paper does not inspire me with confidence.

       However I think its a good point that given the so called pause was definitely not a period of cooling any such cycle (if it exists) is fairly weak and is being dominated by AGW.

11538. nigelj at 05:43 AM on 20 March 2019
       New rebuttal to the myth 'Holistic Management can reverse Climate Change'
       

       Red Baron @18, thanks again and I understand the fixed carbon and soil carbon distinction now, and I did already understand the general nature of the biochemical pathways.

       It's the quantities I struggle with. It appears Nordberg has 10% of the fixed carbon going into soil carbon and Jones has roughly 30 - 40% going into soil carbon, if I read things right. This would still seem to fall somewhat short of Savorys claims, but is obviously a pretty big improvement. That would be what is possibly significant.

       I'm out of my depth trying to compare findings of different studies that seem to measure things a bit differently. I think the writer of the article should address the issues and papers you quote.  

11539. RedBaron at 05:05 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       @12 John Hartz,

       Yes Cell grazing from your link is an early form of Savory's work. It is not the same as HM, because quite a bit more work went into developing HM since the early days when Savory developed cell grazing from Voisin's rational grazing. But yes they are closely related. It is quite possible to get exactly the same results in soil carbon sequestration.

       Cell Grazing

       Cell Grazing the first 10 years in Austrailia

11540. Kevin C at 04:46 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       Still working through the paper list slowly:

       • Gattinger et al (2012) report a “maximum technical potential” of 56 Gt C globally from 2010 till 2030, based on shifting all farming (not just rangeland grazing) to organic. This assumes no economic barriers and that no land is already organicly farmed. That’s one of the highest numbers I’ve found. When extended to 40 years, that would reach about ¼ of Savory’s figure, but by making much more extensive changes.
       • Lai (2010) show in figure 8 an economic potential for sequestration of 0.49 Gt C/yr (or 1.8 Gt CO2eq/yr) from livestock and grazing land management. Over 40 years that makes 20 Gt of carbon.
       • Teague et al (2011) and Teague et al (2016) provide a higher estimate. They estimate 0.8 Gt C/yr for adoption of adaptive multipaddock grazing across the whole of the US. If we were to assume the same benefit worldwide sustained over 40 years, that would give 120 Gt C - still a factor of 4 below Savory.

       My expertise in temperature data does not transfer to animal husbandry. All I'm doing is reading papers carefully and looking for numbers which are actually comparable (to whatever extent possible) and relevant to the question.

11541. Post Vegan at 04:43 AM on 20 March 2019
       New rebuttal to the myth 'Holistic Management can reverse Climate Change'
       

       As noted in my blog entry on methane: Ruminations-Methane math and context. Spikes in atmospheric methane emissions correlate with industrialization, conventional natural gas use, and most recently fractured natural gas. From 1998 to 2007, atmospheric methane levels had leveled out. During this period of time, global cattle inventories increased. Since 2007, global cattle inventories have decreased yet atmospheric levels of CH4 have again started to rise. So there is NO correlation between global cattle inventories and atmospheric CH4 levels. What started in 2006? You betchya, fracking. Typical microbial sources of methane (methogenesis from archae- methanogens) have C12 isotopic signatures of methane while thermogenic sources of methane (fossil fuels) have C13 isotropic signatures of methane. But fracking and coal bed gas also have C12 isotopic signatures. This has led to some confusion in top down analysis of methane sources, especially when very rudimentary inventories of CH4 isotopes have been used. There's a lot of overlap in signatures, but in general some studies have been attributing CH4 to the animal Ag sector that should really be attributed to the natural gas fracking sector. (Note bottom up analysis of CH4 tends to over count and place blame on those sources of methane easier to extrapolate - like cattle- rather than sources of methane harder to account for like leaky gas pipes or the number of cockroaches).

11542. Post Vegan at 04:26 AM on 20 March 2019
       New rebuttal to the myth 'Holistic Management can reverse Climate Change'
       

       Holistic management isn't something one can really understand by reading papers on a computer screen, especially when one relies on papers that don't know the difference between holistic management and short duration grazing [SDG] or rotational grazing [RG]. The whole argument above is built on a house of cards since the author bases a large part of the analysis on Nordborg, who in turn relies on Briske and Holechek. All of these people make the same error. So let me reiterate, holistic management (aka AMP management) and short duration grazing or rotational grazing are not the same thing.

       I didn't fully understand what holistic management was until I attended a few HM workshops and visited a few ranches using these management practices. Savory's talks and book weren't very useful since Savory's writing and speaking styles tends towards the use of a lot of run on sentences with non-parallel structure that tend to obfuscate rather than clarify. His TedTalk was one of his more persuasive talks since because of the time constraint, he was forced to be succinct. Though in this talk, many of the points, he’d normally qualify, were stated without any qualifications.

       Now most people think HM is just another way or system to move cattle. But HM (more specifically holistic grazing), is primarily a process to restore and regenerate land utilizing a holistic ecosystem view. Holistic grazing, also called adaptive grazing, should also be thought of as regenerative or ecological grazing. Holistic grazing mimics nature, regenerates land and restores ecosystem function.

       When starting with HM, the land’s existing conditions are assessed, goals are then determined, and a plan is implemented. That plan is constantly re-assessed and modified to achieve the plan's goals. Goals include improving soil health, greater plant and wildlife diversity, improved forage, improved animal welfare, improved hydrology, increased ground cover, etc. Ranchers using HM are as much soil farmers as they are meat producers. HM isn’t prescriptive. Movements are adapted to the land conditions. Every ranch will have its own unique plan to achieve its goals. Now systems like SDG and RG are systems, with specific movements patterns based on specific set timing irrespective of specific land conditions with the primary goal being cattle weight gains.

       With holistic grazing, ruminants are an essential tool for achieving these restorative and regenerative goals. Ruminants are "all-in-one" tools. They are mowers, seed pushers, ground "indentors", composters, fertilizer spreaders, nutrient cyclers and soil builders. Moreover these four-legged decomposing spreader nutrient cyclers, in the field, don't require any fossil fuels.

       Now the connection between grazing management and carbon sequestration is soil biology, specifically what practices improve biology and which one’s don’t improve biology. Soil biology drive carbon utilzation, respiration and sequestration as well as water infiltration and retention. As the most recent soil science has been finding when root mass is maintained, as I noted above, plants continue to exude exudates into the soil. When plants are grazed more than 50%, the plants lose most of their root mass. This is why cattle in HM or AMP systems have to be frequently moved. The tops of plants also have the most nutrition. Additionally when ruminants eat the tops, they are less exposed to worms and other potential pathogens closer to the soil. All the animal movements are based on field observations of plant growth and ground cover, not a specific pattern or timing as with SDG or RG systems. So once again, HM and SDG/RG are not the same thing.

       Cattle’s urine, manure and saliva function as inoculates that increase plant growth. Ruminants, including cattle’s ancestors’ auroch, co-evolved with vegetation in grassland ecosystems. Grasses have nodes, so when bit they regrow from those nodes. The manure in healthy grassland ecosystems is broken down quickly by different types of dung beetles that quickly move the dung into the earth and thus reduce any methane off gassing. This helps build soil. But the primary mechanism for building soil, again as I noted previously, is microbial necromass accumulation. Up until recently, the general belief was that top soil takes hundreds of year to accumulate through mineralization. MacArthur Fellow, and geologist Dr. David Montgomery in his last two books, The Hidden Half of Nature and Growing a Revolution, does an excellent job of dispelling this belief by illustrating how better soil conservation agricultural practices, including livestock integration, speed up top soil formation significantly. So, as I noted in my prior response, more soil accumulates and captures more carbon. There isn’t a finite amount of soil, so there isn’t a finite of carbon capture, thus the whole premise of “saturation” is a flawed one except for in a degenerated system where no more soil is accumulating.

       Better land management, including better grazing and agricultural practices, also maintain arbuscular mycorrhizal fungi [AMF] networks. When land is over grazed, tilled or treated with syn N, those AMF networks are destroyed. These networks connect plants and per preliminary research seem to play a huge role in the amount of carbon that can be sequestered. Dr. David Johnson, a microbiologist at New Mexico State University, did two self-financed research studies that showed massive increases in carbon sequestration coupled with decreased carbon respiration when fungi to bacteria ratios were improved. Johnson’s carbon sequestration numbers were 10 to 20 times those of Lal. Johnson’s numbers were so good, that one of the conservative peer reviewers didn’t believe those numbers, so both of Johnson’s paper were not accepted for publication. Though currently, several places across the globe including the new regenerative Ag program at Cal State Univ. Chico, are replicating Johnson’s studies to (hopefully) validate Johnson’s numbers. In the meantime, Johnson has made his composting methodology reading available online for anyone to replicate. This is a non-proprietary, non-licensed methodology, so Johnson doesn’t gain a dime directly from his processes. Here’s a good recent talk by Johnson at Cal St. Univ. –Chico where he discusses his research: Regenerating the Diversity of Life in Soils: Hope for Farming, Ranching and Climate.

11543. Post Vegan at 03:51 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       I've writen more about the importance of soil biology in this blog entry : It's the Soil Biology, Stupid. 
       
       Climate scientists and soil scientists as well as botanists really need to get out of their respective silos and talk to one another. Obviously we live in an interconnected (rather than reductive) world. For example: Carbon dioxide converted to glucose via the krebs cycle gets exuded and feeds soil microbes, which in turn, improves soil structure thus allowing for more water infiltration and retention. Thus more plant growth. More plant growth versus bare ground means more cooling immediately at the surface level. Plus plants transpire monoterpines like isoprene and pine which when oxidized become nuclei essential for rain cloud formation. Thus consolidation of water vapor leads to cooling as well as more cloud formation which reflects solar radiation…and thus more cooling. The more soil is recarbonized, the less evaporation and the more plant growth, so less water vapor and more cloud formation. Capiche?

       Anyway, I’ll be writing something about these interconnections soon, until then here’s something else I wrote that is a more systems view of methane: Ruminations- Methane math and context.

       All this reductive thinking like noted in the author’s myth busting gives everyone who is more mindful a lobotomy. We should be asking more questions rather than trying to “prove” all the time that others are “wrong”.

11544. Post Vegan at 03:33 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       Holistic management isn't something one can really understand by reading papers on a computer screen, especially when one relies on papers that don't know the difference between holistic management and short duration grazing [SDG] or rotational grazing [RG]. The whole argument above is built on a house of cards since the author bases a large part of the analysis on Nordborg, who in turn relies on Briske and Holechek. All of these people make the same error. So let me reiterate, holistic management (aka AMP management) and short duration grazing or rotational grazing are not the same thing.
       
       I didn't fully understand what holistic management was until I attended a few HM workshops and visited a few ranches using these management practices. Savory's talks and book weren't very useful since Savory's writing and speaking styles tends towards the use of a lot of run on sentences with non-parallel structure that tend to obfuscate rather than clarify. His TedTalk was one of his more persuasive talks since because of the time constraint, he was forced to be succinct. Though in this talk, many of the points, he’d normally qualify, were stated without any qualifications.

       Now most people think HM is just another way or system to move cattle. But HM (more specifically holistic grazing), is primarily a process to restore and regenerate land utilizing a holistic ecosystem view. Holistic grazing, also called adaptive grazing, should also be thought of as regenerative or ecological grazing. Holistic grazing mimics nature, regenerates land and restores ecosystem function.
       
       When starting with HM, the land’s existing conditions are assessed, goals are then determined, and a plan is implemented. That plan is constantly re-assessed and modified to achieve the plan's goals. Goals include improving soil health, greater plant and wildlife diversity, improved forage, improved animal welfare, improved hydrology, increased ground cover, etc. Ranchers using HM are as much soil farmers as they are meat producers. HM isn’t prescriptive. Movements are adapted to the land conditions. Every ranch will have its own unique plan to achieve its goals. Now systems like SDG and RG are systems, with specific movements patterns based on specific set timing irrespective of specific land conditions with the primary goal being cattle weight gains.
       
       With holistic grazing, ruminants are an essential tool for achieving these restorative and regenerative goals. Ruminants are "all-in-one" tools. They are mowers, seed pushers, ground "indentors", composters, fertilizer spreaders, nutrient cyclers and soil builders. Moreover these four-legged decomposing spreader nutrient cyclers, in the field, don't require any fossil fuels.

       Now the connection between grazing management and carbon sequestration is soil biology, specifically what practices improve biology and which one’s don’t improve biology.  Soil biology drive carbon utilzation, respiration and sequestration as well as water infiltration and retention.  As the most recent soil science has been finding when root mass is maintained, as I noted above, plants continue to exude exudates into the soil. When plants are grazed more than 50%, the plants lose most of their root mass. This is why cattle in HM or AMP systems have to be frequently moved. The tops of plants also have the most nutrition. Additionally when ruminants eat the tops, they are less exposed to worms and other potential pathogens closer to the soil. All the animal movements are based on field observations of plant growth and ground cover, not a specific pattern or timing as with SDG or RG systems. So once again, HM and SDG/RG are not the same thing.

       Cattle’s urine, manure and saliva function as inoculates that increase plant growth. Ruminants, including cattle’s ancestors’ auroch, co-evolved with vegetation in grassland ecosystems. Grasses have nodes, so when bit they regrow from those nodes. The manure in healthy grassland ecosystems is broken down quickly by different types of dung beetles that quickly move the dung into the earth and thus reduce any methane off gassing. This helps build soil. But the primary mechanism for building soil, again as I noted previously, is microbial necromass accumulation. Up until recently, the general belief was that top soil takes hundreds of year to accumulate through mineralization. MacArthur Fellow, and geologist Dr. David Montgomery in his last two books, The Hidden Half of Nature and Growing a Revolution, does an excellent job of dispelling this belief by illustrating how better soil conservation agricultural practices, including livestock integration, speed up top soil formation significantly. So, as I noted in my prior response, more soil accumulates and captures more carbon. There isn’t a finite amount of soil, so there isn’t a finite of carbon capture, thus the whole premise of “saturation” is a flawed one except for in a degenerated system where no more soil is accumulating.

       Better land management, including better grazing and agricultural practices, also maintain arbuscular mycorrhizal fungi [AMF] networks. When land is over grazed, tilled or treated with syn N, those AMF networks are destroyed. These networks connect plants and per preliminary research seem to play a huge role in the amount of carbon that can be sequestered. Dr. David Johnson, a microbiologist at New Mexico State University, did two self-financed research studies that showed massive increases in carbon sequestration coupled with decreased carbon respiration when fungi to bacteria ratios were improved. Johnson’s carbon sequestration numbers were 10 to 20 times those of Lal. Johnson’s numbers were so good, that one of the conservative peer reviewers didn’t believe those numbers, so both of Johnson’s paper were not accepted for publication. Though currently, several places across the globe including the new regenerative Ag program at Cal State Univ. Chico, are replicating Johnson’s studies to (hopefully) validate Johnson’s numbers. In the meantime, Johnson has made his composting methodology reading available online for anyone to replicate. This is a non-proprietary, non-licensed methodology, so Johnson doesn’t gain a dime directly from his processes. Here’s a good recent talk by Johnson at Cal St. Univ. –Chico where he discusses his research: Regenerating the Diversity of Life in Soils: Hope for Farming, Ranching and Climate

11545. John Hartz at 03:06 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       I just came across this ABC News (Australia) video and it may or may not relate directly to the ongoing discussion on this thread.

       Boorowa farmer, David Marsh, began his journey into regenerative agriculture in the 1980s, after a drought brought him to the edge of ruin. He began adopting regenerative practices in 1999, increasing the amount of native vegetation and tree coverage on his property from just 3 per cent to 20 per cent.

       Regenerative farming has helped transform the landscape of dry properties, ABC News (Australia), Mar 14, 2019

11546. michael sweet at 02:21 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       Nick Palmer:

       Statements like "which is probably not covered, or fully conceived of, in the IPCC chapter" and "I don't think this aspect is covered by the IPCC chapter" do not make for a very convincing argument.  Either it is covered or it is not. 

       Since the IPCC includes very experienced scientists who have certainly heard about all aspects of soil science it seems to me that it would be covered.  If it was not covered, the proponents of holistic management could have asked questions and gotten it in.

11547. Nick Palmer at 02:10 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       Kevin C wrote: "Chapter 11 reviews the potential for CO2 mitigation from agriculture and land restoration, with figure 11.13 being particularly relevant. According to this figure, the potential CO2 emissions mitigation from grazing land management, land restoration and livestock is about 2 GtCO2eq/year, or about 5% of our current emissions at the highest carbon price of $100/tonne. If we were to achieve this level of mitigation continually for 40 years, that would be 80 GtCO2eq or 22 tT C, or 5% of Savory’s estimate."
       
       For those readers who don't know, 'Kevin C' is a heavyweight climate scientist. I think the IPCC figures given above relate to 'conventional' soil restoration and grazing management. As I wrote, I think Allan Savory claims too much in his headline statements, but I'm pretty sure his figures include large contributions from reversing desertified and highly degraded land which is probably not covered, or fully conceived of, in the IPCC chapter. Whether his techniques can do that, of course, is a subject of debate...

       It's a truism that many giant agricultural fields have very low soil carbon in them nowadays due to the way they are cultivated - much lower, percentage wise, than the soil would have had when first cultivated. Industrial agriculture has denuded carbon from the soil and the quantities are thought provoking.  As a thought experiment, just assume that all land we use for food crops and livestock on earth has a SOM of, say 3%. Given that, if we could increase that average up to, say, 6% then a relatively simple calculation shows that just about all current greenhouse emissions could be absorbed  by this increased 'sink', but also that some way could be gone towards sucking historic CO2 emissions back out the atmosphere.
       
       There are, of course, known limits to increasing soil organic matter conventionally, as has been mentioned. For example, just piling on endless tonnes of compost has only a temporary effect - bacteria 'respire' much if it right back out again in to the atmosphere as CO2 - unless one simultaneously addresses recreating the bacterial and fungal etc ecosystems that conventional agriculture has degraded. Building up them the long lived humic acids and glomalins  creates soil carbon that is much more resistant to breakdown. I don't think this aspect is covered by the IPCC chapter.

11548. RedBaron at 00:49 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       @6 Nick,

        Even Savory doesn't claim that. He clearly states in many interviews that part of HM includes renewable energy and reducing emissions as a holistic approach to AGW mitigation. There are some people out there claiming a silver bullet, but Savory is not one of them actually. This is from his plan:

       A Two-Path Strategy is Essential for Combating Combat Climate Change

       1.  High Technology Path. This path, based on mainstream reductionist science, is urgent and vital to the development of alternative energy sources to reduce or halt future emissions.
       2. Low Technology Path. This path based on the emerging relationship science or holistic world view is vital for resolving the problem of grassland biomass burning, desertification and the safe storage of CO2, (legacy load) of heat trapping gases that already exist in the atmosphere.

       You can read his whole plan here:

       A Global Strategy for Addressing Global Climate Change
       by Allan Savory

11549. Kevin C at 00:49 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       Firstly, we need to establish the scope of the question. There is scientific discussion as to whether holisitic management provides significant benefits over other managed grazing techniques (and of course there is no doubt that managed grazing provides benefits over mismanaged grazing). Conclusions vary both by location and by the field of the researchers, with sociologists (who talk to the farmers) more positive than experimental agriculturalists (who rely more on measurements). While extremely interesting from a scientific viewpoint, this is not a relevant question for Skeptical Science.

       The question which is key to the work of Skeptical Science is whether Savory’s very specific claims about the ability of holistic management to extract CO2 from the atmosphere at levels sufficient to reverse climate change are credible. Savory claims that over a period of 40 years the application of holistic management could remove 500 Gt of CO2 from the atmosphere.

       So lets start with the IPCC report (AR5 WG3), since it is a comprehensive assessment by some of the best people in the field. Chapter 11 reviews the potential for CO2 mitigation from agriculture and land restoration, with figure 11.13 being particularly relevant. According to this figure, the potential CO2 emissions mitigation from grazing land management, land restoration and livestock is about 2 GtCO2eq/year, or about 5% of our current emissions at the highest carbon price of $100/tonne. If we were to achieve this level of mitigation continually for 40 years, that would be 80 GtCO2eq or 22 tT C, or 5% of Savory’s estimate. Taking the upper 1 sigma bound only leads to a small increase in this value.

       Note however that this is based in part on reductions in emissions rather than uptake, and ignores the issue of non-permenance of additional soil sequestered carbon (section 11.3.2), both of which reduce the expected mitigation potential.

       Are there estimates of the long term carbon sequestration potential of soils under improved grazing or other management schemes? Eagle et al (2010), which is the primary source for the Delgado paper cited by Red Baron, lists two 40 year studies (table 23), with one showing no change from altered grazing practices, and the other showing a small increase in sequestration (0.66 tCO2eq/ha yr, 0.2 tC/ha yr) from a change in grazing. For single year studies, Eagle finds the CO2 sequestration potential of rangeland as uncertain and varying in sign from study to study.

       The two Retallack papers cited by Red Baron don’t seem to be relevant – the first deals with very long timescales (~10Kyr). The second contains a brief speculative section at the end, but does not offer any data except for a citation to Sanderman (2010), who in turn cites Connant (2001), which was a source work for this rebuttal and found vary variable results from different studies. Sanderman also notes that “On average, 1-2% of plant residues become stabilised as humified soil organic matter for significant periods of time (Schlesinger 1990).” highlighting the importance of the permenance issue.

       I'll try and work through a couple more of the suggested papers this evening.

11550. Kevin C at 00:42 AM on 20 March 2019
       Holistic Management can reverse Climate Change
       

       A couple of comments to facilitate the discussion. First, let me set some context. (This post could go at the bottom of any rebuttal.)

       The aim of Skeptical Science is to communicate what we as a species know (and don’t know) about climate change, and to call out claims which misrepresent what we as a species know about climate science.

       This raises the question of how we, as a species, can know something. Clearly, there are things that we do know – that the earth is round and orbits the sun. A few people dispute these things, but we consider it nonetheless as something that is known. So how do we know that we know?

       The answer is laid out in lay terms in this talk by science historian Naomi Oreskes, and in many more academic talks she and others have given on the same subject. The problem is that people are human, and have incomplete information and cognitive biases. So we can’t trust people. Scientists train themselves to focus on evidence, but are still people, and so not very reliable. Scientific papers are a little more reliable, because of two additional social factors – when we attach our name to a paper, some of our reputation goes with it, and also the paper should be rigorously critiqued by (when the system works) independent scientists looking to find holes in our work. But science is hard, so we still expect many individual papers to be wrong. The best measure of what we as a species know comes from an assessment of all of the scientific literature on the question, because more diverse and more dispersed groups are less subject to groupthink and other biases.

       When we address a claim on SkS, we have to have a standard against which to evaluate a claim. And the most reliable standard is to compare that claim against the whole body of scientific opinion relevant to that claim. We expect a diversity of opinion, but we can assess the breadth of diversity on a particular question. We can then identify whether a particular claim is representative of the scientific knowledge on a particular question, or whether it is part of a spectrum of diverse opinions. In the latter case we can further identify whether the claim falls in the middle of that spectrum, on the edge, or is an extreme outlier with little other support.

       Obviously this can’t be done by citing individual papers, it must be done on the basis of an extensive review. Hence the lengthy citation list. We expect to find outliers on any question – I’ll discuss some of these later. However, we also expect multiple systematic reviews to reach similar conclusions, so comparison with the IPCC reports is an important starting point.

       So, that raises two questions:

       1. Where do Savory’s claims stand with respect to the spread of scientific opinion on those questions?
       2. Does the rebuttal do a good job of communicating the spread of scientific opinion and the relative position of Savory’s claims?

       I'll try and look into the first of these in my next post.

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