Guest Essay by Dr. Gavin Schmidt, NASA GISS
Yesterday, I carried this story: An alarmist prediction so bad, even Gavin Schmidt thinks it is implausible
Today, on Twitter, Karel Haverkorn asked why. To his credit, Dr. Schmidt replied on Twitter in multiple tweets with an essay of bullet points. This marks the first time Dr. Schmidt publishes on WUWT, as well as the first essay here ever composed on Twitter.
I’ve collated his responses below.
Also the PETM (55 My) and Eocene small events. But no evidence under near-current temps. Outside of quaternary range of arctic temps, many fewer constraints…. Pliocene CH4 may well have been higher (but no direct evidence), multiple sources though…
Some more context on Arctic methane release story to follow:
1) Methane is an important part of the anthropogenic radiative forcing over 20thC. Human caused increase from 0.7ppm to 1.8ppm
2) Methane emissions have a direct GHG effect, and they effect atmospheric chemistry and strat water vapour which have additional impacts
3) Direct forcing from anthropogenic methane ~0.5 W/m2, indirect effects add ~0.4 W/m2. (For ref: CO2 forcing is ~1.8W/m2)
4) natural feedbacks involving methane likely to be important in future – via wetland response to T/rain chng, atmos chem &, yes, arctic src
5) monitoring and analysis of atmos conc of CH4 is very important. However, despite dramatic Arctic warming and summer sea ice loss ….. > …. In recent decades, little change has been seen in atmos concentrations at high latitudes.
6) There are large stores of carbon in the Arctic, some stored as hydrates, some potentially convertible to CH4 by anaerobic resporation
7) there’s evidence in deep time records of large, rapid exogenous inputs of carbon into climate system; leading theory relates this to CH4
8) it is therefore not silly or alarmist to think about the possibilities, thresholds and impacts for these kinds of events
9) in more recent past, there have been a number if times when Arctic (not necessarily globe) has been significantly warmer than today.
10) Most recently, Early Holocene, which had significantly less summer sea ice than even 2012. Earlier, Eemian 125kyrs ago was sig warmer
11) At neither of these times is there any evidence for CH4 emissions or concentrations in excess of base pre-industrial conditions.
12) this means that we are not currently near a threshold for dramatic CH4 releases. (Though we may get there)
13) Much of the concern re dramatic changes in Arctic methane come from one off surveys and poorly calibrated remote sensing
16) But we should not take what-if sensitivity experiments as predictions.
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Addenddum:
Dr. Judith Curry also thinks the “methane time bomb” is implausible.
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His comments are sound.
It’s funny how scientists can suddenly think sceptically when the predictions are in a testable timescale.
I blame String Theory for letting academics think untestable waffle has different rules. They don’t.
The rules used here are universal for all hypotheses.
John West says:
July 25, 2013 at 10:23 am
“PS: It’s twitter responses, not an intentional WUWT post by Gavin.”
I know, But Dr. Gavin Schmidt will get around to finnd and read this, I’m sure. And he won’t answer me. But he will read my questions. And he will know the answers.
I think a question that needs to be asked more often, is, if we do everything possible to reduce our “carbon footprint” (and our economy goes into a “death spiral”, reducing carbon emissions even more), then how long will it be until we notice a change in the climate?
Thanks Anthony. Dr. Schmidt is most correct in his tweets and it is good to see this acknowledged.
9) in more recent past, there have been a number if times when Arctic (not necessarily globe) has been significantly warmer than today.
10) Most recently, Early Holocene, which had significantly less summer sea ice than even 2012. Earlier, Eemian 125kyrs ago was sig warmer
11) At neither of these times is there any evidence for CH4 emissions or concentrations in excess of base pre-industrial conditions.
12) this means that we are not currently near a threshold for dramatic CH4 releases. (Though we may get there)
————————–
Early Holocene had recently inundated the frozen tundra of the ESAS plain, this impenetrable barrier to clathrate release is no longer intact, so one cannot deduce that the early Holocene proves anything. The Eemian is not “significantly” warmer but rather is only a few degrees warmer in the arctic, this is equivalent to about 1C of additional warming on a planetary average (the arctic is warming 2.5 to 3.5 X faster and once we reach ice-free arctic summers there will be a step-change in temperatures, a steep rise.
However, the Eemian was caused by a Milankovich cycle, its process was much much slower in scale, it also had super abundance (compared to today) of land and sea based biomass carbon sequestration organisms, which would be able to mitigate the release of natural carbon on a slower time scale.
Finally, during the Eemian, there was a natural feedback mechanism that successfully turned the climate before the largest potential CH4 release could occur, this AMOC fluctuation produced a resurgence of the last glacial cycle once we went past the peak of the Northern Hemisphere Milankovich cycle.
To contend that these events provide any doubt to the potential for catastrophic CH4 release from the ESAS within the next 100-200 years under current warming scenarios is simply wrong.
Dr. Gavin Schmidt. Welcome warm congratulations and a big thank you, for common sense, integrity and scientific approach.on this Arctic methane subject. Please straddle the middle line between warmist and skeptic more often and maybe revisit some of the GISS adjustments for good or bad, now your ex-boss Mr. Hanson has departed.
I see, so the WUWT’ers welcome Gavin into the fold as a trusted source… when he tells them what they want to hear. It’s not a menu, folks — in for a penny, in for a pound.
Dr. Schmidt, welcome to WUWT. Does this mean you’re prepared to also rethink some other things? For example, might you consider ending the rank censorship that takes place under your leadership at your Real Climate blog, and get rid of the Bore Hole? What message did you send when you petulantly and childishly refused to appear on set with a CAGW critic during that John Stossel TV interview a few months back? Have you ever noticed that WUWT has no problem linking to your site and to even more shamelessly propagandistic CAGW sites (like “SkepticalScience”) while you refuse to link to WUWT? What do you think that means?
Do you appreciate that those you seek to persuade may instead see in your behaviors, editorial choices and control mechanisms, something of a totalitarian, or perhaps even an entire category of study that concludes with certainty before it really understands, that values political aims over objective truth, that’s besot with an intolerant mindset that brooks no criticism? Just askin’ …
Sally people here know it’s not a menu; this is why they call bullshit on bullshit, yet are prepared to acknowledge when someone gets it right even if they are supposedly ‘on the other side’.
The point is, this is science; and properly conducted there’s no place for taking sides. Science is about data, facts, and empirical truths.
Sally,
Dr. Schmidt is still a researcher with a PhD. He had to demonstrate some level of either intelligence or perseverance to achieve that. The post above at gives a glimmer that he can follow the empirical data where it leads. Making some speculation on my own part, this may be as was alluded to by ‘Sunup’ that Dr. Hanson’s departure removes some political pressure within NASA-GISS to actually use data to find answers.
Thanks, Anthony. It’s interesting to see his remarks collated as bullet points like that. It reads well.
I give Gavin high marks for honesty and clarity. I find no fault with his response. It is considered, supported by observations, and is a good summation of what I see as the current state of knowledge about the odds of a catastrophic methane release.
I would only add that his edifice is built on on sand. The sand in this case is the simplistic idea that the change in temperature of the earth is a linear function of the change in total forcing. I know of no other complex natural system for which that kind of linear input-to-output relationship holds true, and I see no evidence for that in the observations of the climate.
w.
jai mitchell says: July 25, 2013 at 12:44 pm
…
LOL, take it up with Dr Schmidt … they’re his tweets. Mann, you’re shallow !
jai mitchell says:
July 25, 2013 at 12:44 pm
“Early Holocene had recently inundated the frozen tundra of the ESAS plain, this impenetrable barrier to clathrate release is no longer intact, so one cannot deduce that the early Holocene proves anything. The Eemian is not “significantly” warmer but rather is only a few degrees warmer in the arctic, this is equivalent to about 1C of additional warming on a planetary average (the arctic is warming 2.5 to 3.5 X faster and once we reach ice-free arctic summers there will be a step-change in temperatures, a steep rise.
However, the Eemian was caused by a Milankovich cycle, its process was much much slower in scale, it also had super abundance (compared to today) of land and sea based biomass carbon sequestration organisms, which would be able to mitigate the release of natural carbon on a slower time scale.”
Finally an expert! Please, Dr. Mitchell, I have two questions I need answered:
– What caused the Younger Dryas?
– What causes the Bond cycles?
TIA
Gavin Schmidt,
Thank you for participating here, albeit initially by a rather abrupt / casual collages of Tweets.
Please come post articles here that do some heavy lifting in some of your fundamental work related to the basis of significant (i.e. dangerous) AGW from burning CO2. That is a sincere request. It would add to an open and independent dialog about the ongoing issues in the young area of climate science. WUWT has a good venue for it.
John
Best bit of science I’ve actually read from Gavin without mumbo jumbo malarkey twisting findings into a cagw spin or responses delivered with self superior condescension.
Actually that bit of cell feed above by Gavin doesn’t deserve the backhanded compliment in my first sentence above. It’s just that Dr. Schmidt has a long cagw religious history he needs to correct.
One step forward adhering to common sense and science is very welcome! We look forward to more open honest science from you, Dr. Schmidt!
Especially since I plan to never return to that poisonous propaganda site realclimate.bogus; (bogus is a definitely intended replacement serving as a descriptor rather than an url type).
John Whitman has a far nicer sentiment than mine. My only quibble is that if Dr. Schmidt plans to post a major CAGW leaning bit of science at WUWT; I ask that Dr. Schmidt break the publication into smaller portions so scientific points, data or code receives proper attention without fracturing the thread into a clamorous row.
Good comment John!
ATheoK on July 25, 2013 at 5:11 pm said,
John Whitman has a far nicer sentiment than mine. [. . .]
Good comment John!
– – – – – – – – –
ATheoK,
Thanks for your kind words.
I have been critical of Gavin Schmidt, but am enthusiastic about the possibility of his participation in open and independent dialog at WUWT on his scientific works.
John
Good to see Dr. Schmidt here, even if it’s only as a series of tweets.
A while back, there was a Scientific American poll – mostly about whether Dr. Curry was a saint or a dupe, but there was a question: “Should climate scientists engage with skeptics or does it just give ’em credibility.?” This question got an amazingly positive response – well beyond any attempt to “game” the poll. Seems like a good idea to me, and I’m glad to see a little of it here. Us skeptics might help out be being a little more “engageable”.
Just so I can be clear, Anthony: is this actually a “guest essay” by Gavin? I mean, did he consciously contact you and propose it as an essay? If so, fine. If not, well, it would be misleading.
REPLY: I contacted him, he didn’t object – Anthony
The main absorption peak for methane is at a wavelength of about 3.3 microns. At this wavelength the radiant flux from the Sun is of the order of 85 times greater than that from an Earth at 15 degrees Celsius. This must result in about 85 times as much infrared radiation from the Sun, at 3.3 microns wavelength, being sent back into space by the absorption and re-radiation from methane molecules in the upper atmosphere as could be re-radiated into the lower atmosphere for infrared radiation sourced from the warmed Earth. Furthermore as the Sun’s radiation is re-emitted into space before reaching the Earth’s surface, that surface will be colder than the assumed 15 degrees Celsius and thus will release even less radiation at all wavelengths.
To conclude, more methane in the atmosphere means a colder Earth, not hotter.
Titan has a 5% methane atmosphere. How much warmer should it be then say… a neighboring moon that has no atmosphere?
Fortunately there is a neighboring moon. It’s called Hyperion. And better, Titan and Hyperion have almost matching albedo which means pound for pound they both absorb and convert the same amount of sunlight into infrared (ie:surface temperature).
So we can do a direct comparison between their surface temperatures and the difference will be the global warming potential of methane. Right?
According to the wikipedias, Hyperion’s surface temperature is 93 K (−180 °C)
TItan’s surface temperature at the Huygens crashsite (equator) 93.7 K (−179.5 °C).
http://en.wikipedia.org/wiki/Hyperion_(moon)
http://en.wikipedia.org/wiki/Titan_(moon)
Where is it? Where’s the warming?
Bevan”s comment @ur momisugly July 26, 2013 at 12:17 am, I’m guessing is based on the physical chemical properties of methane as produced in a lab here on Earth. I don’t think it’s an accident that against all reports of methane as a GHG by people such as Gavin Schmidt, when it’s observed in the wild places of our solar system, methane acts in the manner described by Brevan.
I think this:
http://scottishsceptic.wordpress.com/2013/07/25/wikipedia-warming-becomes-climate-change/
has alot to do with the resent slight tilt toward reality by Gavin Schmidt.
Scottish says that “…the number of active editors (@Wikipedia) have plummeted, those who do contribute clearly have no knowledge of the climate.
They haven’t enough voluntary manpower to police their global warming hokem at wikipedia anymore. That will flat change a moonlighting NASA computer tech’s religion, I think.
9) in more recent past, there have been a number if times when Arctic (not necessarily globe) has been significantly warmer than today.
10) Most recently, Early Holocene, which had significantly less summer sea ice than even 2012. Earlier, Eemian 125kyrs ago was sig warmer
=============
Early Holocene, 8k years ago, a drop in the bucket time wise. A much warmer Arctic, but the polar bears survived. A time when the first evidence of agriculture and the beginnings of our modern civilization first appear. Yet we continue to hear fantasy stories about how bad warming would be for civilization.
Contrast that to 80 thousand years ago when genetic evidence shows that humans were all but wiped out during the ice age that followed the Eemian. Genetic markers show that the worldwide human population was likely reduced to a few hundred individuals. Will we fare any better if we are not able to prevent the next ice age? Perhaps the only thing that will prevent our mass extinction is the CO2 from fossil fuels.
jai mitchell says:
July 25, 2013 at 12:44 pm
Finally, during the Eemian, there was a natural feedback mechanism that successfully turned the climate before the largest potential CH4 release could occur, this AMOC fluctuation produced a resurgence of the last glacial cycle once we went past the peak of the Northern Hemisphere Milankovich cycle.
===============
What was that natural feedback mechanism that “successfully” turned the climate, even though CO2 levels were significantly increased during the Eemian as the oceans warmed? Though it is hard to see how one can call turning the climate back into an ice age as “successful”.
Your agenda is clear. You see a return to ice age conditions as “natural” and thus a good thing. The collapse of civilization and the billions of deaths that would result worldwide are the solution to overpopulation. It would be sunny every day, with forests of unicorns and butterflies.
Funny how there was natural feedback in the Eemian to counter the rising CO2 from the warming oceans. We are told by climate scientists that most certainly know better, that rising CO2 will lead to natural feedback due to increased moisture that will increase the warming and prevent a return to ice age conditions.
Now we hear that the natural feedback mechanism works to counter the warming due to rising CO2 as occurred in the Eemian. Someone needs to tell the IPCC and the climate modellers they have it all wrong.
Like the say, the truth goes on forever, but a lie always has an end. The truth has no contradiction. A lie always at some point contradicts itself, revealing that it is a lie.
The natural feedback mechanism that allowed the Eemian to return to ice age conditions in spite of rising CO2 levels directly contradicts the hypothesis of positive water feedback as theorized by the IPCC, climate science and the global climate models. The contradiction reveals the lie.
7) there’s evidence in deep time records of large, rapid exogenous inputs of carbon into climate system; leading theory relates this to CH4
8) it is therefore not silly or alarmist to think about the possibilities, thresholds and impacts for these kinds of events
<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>
It’s quite a stretch: from “evidence” to “leading theory” and, from thence a claim of robust science which is “not silly or alarmist”. Gavin Schmidt needs to do better than this if he is to convince a scientist who likes good, old fashioned scientific rigor (and there are still lots of these around). But, scientific rigor is the first casualty in this climate business.