"Our greatest responsibility is to be good ancestors."

-Jonas Salk

Wednesday, November 25, 2015

Have We Missed the 2C Target Already?

Even a successful outcome in Paris will be a failure. Oliver Geden says so in a way that is exasperatingly remeniscent of R Pielke Jr., who surely agrees. But their smug insouciance doesn't change the picture - if we've missed the boat, no amount of waiting at the dock will get us on board.

Kevin Anderson avoids saying those words, but it's hard to avoid the conclusion from his recent arguments here (and similarly at Nature here).

I sometimes find Anderson a bit too alarmist on the physics. But I think the thrust of this article is totally and sadly true.

The takeaway points:


integrated assessment models are hard-wired to deliver politically palatable outcomes 
the carbon budgets needed for a reasonable probability of avoiding the 2°C characterisation of dangerous climate change demand profound and immediate changes to the consumption and production of energy for a “likely” chance of 2°C, requires global reductions in emissions from energy of at least 10% p.a. by 2025, with complete cessation of all carbon dioxide emissions from the energy system by 2050 
Whilst the endeavours of the IPCC, since its inception in 1988, are to be welcomed, I have grave reservations as to how the implications of their analysis are being reported. 
ubiquitous use of speculative negative emissions to expand the available 2°C carbon budgets, implies a deeply entrenched and systemic bias in favour of delivering politically palatable rather than scientifically balanced emission scenarios 
In plain language, the complete set of 400 IPCC scenarios for a 50% or better chance of 2°C assume either an ability to travel back in time or the successful and large-scale uptake of speculative negative emission technologies.

the failure of the scientific community to vociferously counter the portrayal of the findings as challenging but incremental suggests vested interests and the economic hegemony may be preventing scientific openness and freedom of expression. 
With a growing economy of 3% p.a. the reduction in carbon intensity of global GDP would need to be nearer 13% p.a.; higher still for wealthier industrialised nations, and higher yet again for those individuals with well above average carbon footprints

there remains an almost global-scale cognitive dissonance with regards to acknowledging the quantitative implications of the analysis, including by many of those contributing to its development. We simply are not prepared to accept the revolutionary implications of our own findings 
the job of scientists remains pivotal. It is incumbent on our community to be vigilant in guiding the policy process 
Whether our conclusions are liked or not is irrelevant. As we massage the assumptions of our analysis to fit within today’s political and economic hegemony, so we do society a grave disservice – one for which the repercussions will be irreversible.


I agree with all of that. As for this claim:

"Only if the life cycle carbon emissions of CCS could be reduced by an order of magnitude from those postulated for an efficiently operating gas-CCS plant (typically around 80g CO2 per kWh24), could fossil fuels play any significant role post-2050."

I can't vouch for it but on the other hand I find it plausible. If true it only makes matters even worse.

Looking at the best case out of Paris, it's clear that the 2.0C boat has sailed and we missed it. So when do we fall back, and to what number? 2.5C? 3.0 C? At this point I have to say that zero net emissions prior to a 3 C commitment would look to me to be a good outcome. Welcome to the "good anthropocene", because the other ones are worse.

I do not buy into the "solving the problem would be ridiculously cheap / stimulate the economy / create jobs" framing at all. We have delayed far too long. This will be a huge hit no matter what.

Is sugarcoating it the best approach for moving the body politic? I guess that's the only argument I can see. "We are going to miss the 2 C target, but if we pretend it's possible that at least keeps our options open for staying under 4 C"? I don't think it is a legitimate role of science to make such a judgment.


Tom said...

I know this will sound like aggravation to you, but honestly, how can you set a carbon budget without knowing what sensitivity is? Doesn't honesty compel you to offer a sliding scale of emissions for differing values for sensitivity?

Susan Anderson said...

Fussing about small differences in sensitivity is nonsense. One doubling will be followed by another, and various events such as permafrost melt are already under way. It's all additive.

The subtleties and niceties of science are used by various arguers as a weapon against noticing reality. The Met Office has it about right today:

"2015 likely to be the warmest on record

"This year’s global average surface temperature is likely to be the warmest on record according to data from the Met Office, and is expected to continue the trend showing 15 of the top 16 warmest years have happened since 2001.

"These findings concur with the World Meteorological Organisation (WMO) findings also announced today."

Michael Tobis said...

While I agree with Susan, there's a more complicated answer that's worth making. Stay tuned and thanks for the question.

Tom said...

Susan, I can believe a second doubling. Not a third. You would need to emit a lot of carbon to get to 1040 ppm concentration.

Susan Anderson said...

Tom, I don't think I mentioned a third doubling. In any case, if it gets to that point, the earth will be unrecognizable from a human point of view. If you just focus on real-world evidence, it appears quite a number of interrelated effects are kicking in a bit faster than we hoped they would.

It could be argued that the baseline is 180, but that was a long time ago and as far as I can see, not conducive to human habitation.

Tom said...

Hi Susan

I have always seen 270 ppm (vol) as the baseline. I think there is little doubt that we will hit 540 ppm. I think we will struggle to hit 1080, and that it's physically impossible to get to 2160 from our emissions alone.

I have made the case at my place of business that in fact much of what is attributed to the effects of global warming today is misattribution. However, I focus on things like drought, heatwaves, storms and other mundane matters. I have not even looked at things like the Pacific Blob, erratic storm tracks in the upper parts of the Northern Hemisphere, etc., so obviously I may be missing something.

BBD said...


I know this will sound like aggravation to you, but honestly, how can you set a carbon budget without knowing what sensitivity is? Doesn't honesty compel you to offer a sliding scale of emissions for differing values for sensitivity?

If there was a serious case for low sensitivity then there might be some policy wriggle room, but the evidence that ECS / 2 x CO2 is >2C and probably close to 3C is compelling. This is doubtless why many people tend to view 'lukewarmer' arguments as aggravating.

I have made the case at my place of business that in fact much of what is attributed to the effects of global warming today is misattribution.

What can I say? Politely, I venture that blog science doesn't really cut it.

Tom said...

Ah, BBD--as I'm not a scientist, your comment is less than relevant. If the evidence of sensitivity being above 2C were indeed compelling, I imagine the IPCC would have left the range from AR4 at 2C-4.5C, instead of changing it in AR5 to 1.5C-4.5C. Are you agitating against the IPCC in particular, or climate science in general?

BBD said...


Since you aren't a scientist, your views on attribution are of no consequence - you need reminding from time to time.

As for the *risk* involved in picking the lowest value in a range instead of the best estimate (which remains ~3C), well, I think that speaks for itself. Especially as values under 2C are incompatible with palaeoclimate behaviour.

BBD said...

Oh and Tom, the lowball estimates of S so beloved of lukewarmers arise from limitations in the methodology used to obtain them. See Knutti & Rugenstein (2015) Feedbacks, climate sensitivity and the limits of linear models.

I shouldn't be surprised if we see the lower bound back at 2C in AR6.

Tom said...

Then why did the IPCC lower the low end of the range to 1.5C? Apparently climate scientists are a little less sure than you are.

But then, you're not a scientist so your views aren't worth anything, right?

BBD said...

Then why did the IPCC lower the low end of the range to 1.5C? Apparently climate scientists are a little less sure than you are.

On the basis of then-novel results derived from EBMs. Which turn out to be biased low. The IPCC doesn't *do* science, it just summarises it. Things have moved on.

It's fine for a non-expert to report the expert position. It's not fine for a non-expert to disagree with the expert position on the basis of sod-all actual expertise.

Tom said...

Thanks for telling us all what we can and cannot do. I'll file your instructions in the appropriate place.

Susan Anderson said...

For evidence, this is too narrow and specific, but it gives the flavor. Bearing in mind that 14 of the 15 hottest years happened since 2000. Granted, once the El Nino is over we will have a fallback like we did in 1999. But the baseline keeps moving up, the trends keep adding, and various add-ons keep kicking in, like permafrost melt and all (second link, 7 minutes of wakeup call).

On one of the public television stations tonight, this was devastating on the subject of Russian permafrost, satisfyingly visual and up to date. Rinsing off old critter bones is fascinating. "more biomass is being released here than in all the world's jungles ... finding excrement ... it's fresh soil":

I've just been through a multiple ding-dong with people namecalling me and telling me I'm namecalling them. It's hard to argue with someone whose opinion is preformed and who won't actually read and look at what one is writing and showing.

Tom said...

Hi Susan,

I think your fears regarding permafrost melting are somewhat overblown. Would you accept the U.S. Climate Change Science Program as a moderating influence regarding this topic? (Found via Skeptical Science):

"Destabilization of hydrates in permafrost by global warming is unlikely over the next few centuries (Harvey and Huang, 1995). No mechanisms have been proposed for the abrupt release of significant quantities of methane from terrestrial hydrates (Archer, 2007). Slow and perhaps sustained release from permafrost regions may occur over decades to centuries from mining extraction of methane from terrestrial hydrates in the Arctic (Boswell, 2007), over decades to centuries from continued erosion of coastal permafrost in Eurasia (Shakova [sic] et al., 2005), and over centuries to millennia from the propagation of any warming 100 to 1,000 meters down into permafrost hydrates (Harvey and Huang, 1995)"

BBD said...


Thanks for telling us all what we can and cannot do. I'll file your instructions in the appropriate place.

I'm just the messenger, Tom. Why don't you put your gun away and read the reference? Why the absolute resistance to an opportunity to improve your topic knowledge?

Susan Anderson said...

Tom, please give 7 minutes of your time to watching this. I'm not talking about hydrates. You appear to be advocating/arguing/changing the subject rather than taking in the information. For ease of use, I've made it a direct link: Siberian Permafrost

I don't need perspective on the science, I've been following it for over a decade and I know where all the questions are. What is happening is that practical evidence is pouring in. This is a useful resource, so please don't again dismiss it with a handy reference to something you think will persuade me and anyone else reading to ignore my offering to the sum of understanding.

Scientific uncertainty and honesty are being exploited to undermine its credibility. This is a dishonest. The stakes are enormous, all life on earth, and I don't take much comfort from the possible delay of consequences a couple generations. On that subject, here's another good article, part of which I've extracted in consideration of NYTimes access issues, it's a bit long.

Tales of a Warmer Planet

All quote:
It's a mistake to think the climatic effects of our carbon emissions will be over within a few decades or centuries. Our intergenerational responsibilities run much deeper into the future ... we are now a force of nature on a geological scale. By running our civilization on fossil fuels, we are both creating and destroying climates that our descendants will live in tens, if not hundreds, of thousands of years from now.

Carbon atoms do not disappear when we burn them into carbon dioxide. Isotopic tracer studies show that they work their way into the very fabric of life on Earth. Some of them travel up the food chain from the atmosphere to plants to animals to our dinner plates. Roughly one-eighth of the carbon in your flesh, hair and bones recently emerged from smokestacks and tailpipes. We are not only a source of air pollution — we are air pollution, and our waste fumes will henceforth be woven into the bodies of our descendants, too.

This inert fossil fuel carbon inside us has no direct effect on our health, although mercury and other pollutants that often accompany it amid industrial and automotive emissions may harm us. Most of the airborne carbon will eventually dissolve into the oceans, leaving a sizable fraction of it aloft until it, too, is removed by chemical reactions with carbonate and silicate minerals in rocks and sediments.

That’s the good news.

The bad news is that the natural mopping up of our mess will be extremely slow. Research by the University of Chicago oceanographer and climate scientist David Archer and others shows that the cleanup will take tens of thousands of years even if we switch quickly to renewable energy sources. When the Earth’s slow cyclic tilting and wobbling along its eccentric orbital path once again leads to a major cooling period some 50,000 years from now, enough of our heat-trapping carbon emissions will still remain in the atmosphere to warm the planet just enough to weaken that chill. In other words, our impacts on global climate are so profound that we will have canceled the next ice age.
As pioneers of the Anthropocene, we are an immensely powerful force of nature and can accomplish great things if we not only learn what is scientifically true, but also do what is morally right. Pope Francis tells us that “there is nobility in the duty to care for creation.” As a climate scientist who welcomes international action to address climate change, I offer a heartfelt “Amen” to that.
End quote

"Curt Stager is a professor of natural sciences at Paul Smith’s College and the author of “Deep Future: The Next 100,000 Years of Life on Earth.”"

Tom said...

Hi Susan, many thanks for the link. Sadly, I get an Error 404 for the page and every other permutation of the URL that I tried. I'm sorry I misunderstood the focus of your question.

If I find the video you linked I will certainly watch it. Absent that, I have read a bit about land-based permafrost and came away with the impression that scientists are not overly concerned about land-based permafrost in quantities sufficient to affect the climate. Perhaps the articles I read were overly optimistic.

A quick search finds Schuur et al 2015. I present their abstract without comment:

"Large quantities of organic carbon are stored in frozen soils (permafrost) within Arctic and sub-Arctic regions. A warming climate can induce environmental changes that accelerate the microbial breakdown of organic carbon and the release of the greenhouse gases carbon dioxide and methane. This feedback can accelerate climate change, but the magnitude and timing of greenhouse gas emission from these regions and their impact on climate change remain uncertain. Here we find that current evidence suggests a gradual and prolonged release of greenhouse gas emissions in a warming climate and present a research strategy with which to target poorly understood aspects of permafrost carbon dynamics."

Unknown said...

For what it's worth, Richard Alley on climate sensitivity, AGU 2013:


Steve Bloom said...

Without comment... or research... or much thought.

But here's the stripped url for you, Tommy: http://www.dw.com/en/rescuing-the-russian-permafrost/av-18876625. Yeah, those Russians sound pretty panicked. Maybe they need to take up astronomy.

Oops, a newly panicked Russian, as it happens the leading permafrost researcher (and a Schuur et al. co-author):

'Worries over the current state of permafrost have been reinforced by Prof Romanovsky.

'A professor at the University of Alaska, he is also the head of the Global Terrestrial Network for Permafrost, the primary international monitoring programme.
'He says that in the northern region of Alaska, the permafrost has been warming at about one-tenth of a degree Celsius per year since the mid 2000s.

'"When we started measurements it was -8C, but now it's coming to almost -2.5 on the Arctic coast. It is unbelievable - that's the temperature we should have here in central Alaska around Fairbanks but not there," he told BBC News.

'In Alaska, the warming of the permafrost has been linked to trees toppling, roads buckling and the development of sinkholes.

'Prof Romanovsky says that the current evidence indicates that in parts of Alaska, around Prudhoe Bay on the North Slope, the permafrost will not just warm up but will thaw by about 2070-80.

'"It was assumed it would be stable for this century but it seems that's not true any more," he told BBC News.'

Assumed by who? Er, Schuur et al. (2015). Speaking of which, here's a public copy.

But it gets worse (open access article):

"Recent Arctic tundra fire initiates widespread thermokarst development

"Fire-induced permafrost degradation is well documented in boreal forests, but the role of fires in initiating thermokarst development in Arctic tundra is less well understood. Here we show that Arctic tundra fires may induce widespread thaw subsidence of permafrost terrain in the first seven years following the disturbance. Quantitative analysis of airborne LiDAR data acquired two and seven years post-fire, detected permafrost thaw subsidence across 34% of the burned tundra area studied, compared to less than 1% in similar undisturbed, ice-rich tundra terrain units. The variability in thermokarst development appears to be influenced by the interaction of tundra fire burn severity and near-surface, ground-ice content. Subsidence was greatest in severely burned, ice-rich upland terrain (yedoma), accounting for ~50% of the detected subsidence, despite representing only 30% of the fire disturbed study area. Microtopography increased by 340% in this terrain unit as a result of ice wedge degradation. Increases in the frequency, magnitude, and severity of tundra fires will contribute to future thermokarst development and associated landscape change in Arctic tundra regions."

Yet more homework for the Schuur et al. author team, it seems.

But hmm, how bad could that really get? As it happens, pretty bad. Not as bad as the PETM, perhaps, as our supply of yedoma is lower, but with the full range of carbon feedbacks likely to be triggered by such burning, maybe nearly so.

But no worries. On a scale of next Tuesday, all of this will be quite gradual.

Tom said...

Glad to see someone still reads Skeptical Science.

The IPCC AR5 wrote that permafrost over the 21st century may decrease by up to 20%, and then later start to increase again. https://ipcc-wg2.gov/AR5/images/uploads/WGIIAR5-Chap3_FGDall.pdf. However, this is included in model scenarios.

The Long-Term Projections chapter notes that it is “Possible that permafrost will become a net source of atmospheric greenhouse gases (low confidence).” The Biogeochemical Cycles chapter states “under sustained Arctic warming, modelling studies and expert judgments indicate with medium agreement that a potential combined release totalling up to 200 PgC as carbon dioxide equivalent could occur by the year 2100.”

Referring to phenomena that have been remarked upon for centuries--e.g., fires in the permafrost--may boost recruitment to the Sierra Club (say thanks to the fossil fuel companies that fund you, Steve) but probably contribute little to our understanding of climate change, as opposed to climate.

Steve Bloom said...

Hi Tommy, point to another similar fire in the yedoma.

Another fib: "The IPCC AR5 wrote that permafrost over the 21st century may decrease by up to 20%, and then later start to increase again." Under RCP 2.6 only, note. But the assumptions underpinning that conclusion are toast, as is RCP 2.6 itself.

More broadly, the AR5 permafrost section is history, sadly, as is much of the rest of the cryosphere material. Anyone who is not an obdurate denier can update themselves here.

Tom said...
This comment has been removed by a blog administrator.
Steve Bloom said...
This comment has been removed by a blog administrator.
Susan Anderson said...

Sorry about my lame links; I blobbed the NYT one as well.
I had a lot of trouble submitting, it kept telling me it was wrong, but it worked at the time. It was just a copy of the one I used earlier. To be honest, when I viewed it for the third time, there was stuff in there that detracted from my point, which is that the Taiga, the boreal forest etc. are vast and the scale of dissolution huge.

(the purple area)

There have been a lot of fires, too, and they are often uncontrollable, which also contributes to ice melt etc., as it gets blown about a lot. You can check these out at Earth Observatory:

Today's (December 1) is quite spectacular, space image of Chinese haze. And if all that haze goes away, we will lose it's moderating effect as well.

This is just one of many changing aspects of the full global ecosystem. Steve Bloom's ICCI thresholds piece is quite something. We have to hope it isn't true, but those are real dangers, approaching rather faster than is comfortable.

Focus on arguing is actively dangerous in the face of the past 30 years of doubt and delay, since we pretty much have known about all this that long, not the detail and additional complications that are now beginning to play out in real time, but the big outlines.

Steve Bloom said...
This comment has been removed by a blog administrator.
Michael Tobis said...

Steve, make your point without the ad hominems or make it elsewhere, please.

Steve Bloom said...

Double standard showing again, Michael? As well, I think you're a bit unclear as to what constitutes an ad hominem. Now, Tommy's references to the Sierra Club and Skeptical Science, *those* were ad hominems. And oh look, you allowed them.

Anyway, no problem, I'll remove myself from any future discussion here just as I did at p3 (IIRC for the exact same cause). I was kind of thinking I should do so anyway after your declaration that you won't be attending more climate demos because dirty hippies (or whatever your problem was), so it works out.

Susan Anderson said...

Oh dear, Steve Bloom was making valuable contributions here, imnsho. And if we are to talk about dirty ex-hippies, I'm one (or sorts).

However, Steve, if you read this, I would complain that your response gave mt the high ground, and since I value you both, that's a loss for me and my ilk.

Michael Tobis said...

Steve Bloom makes good points sometimes, but his confrontational style doesn't sit well with what I try to accomplish in these discussions.

It's hard to be perfectly fair in these assessments, but Fuller actually is trying to be polite this time (he asked me to remove a snarky comment). People are stubborn, the more so the more they identify with past public positions. I don't expect much change in Fuller's anytime soon; as long as he chooses to act respectfully I will share what he has to say.

But my rule stands; each contribution is judged on its own, based on whether it improves on silence. It's a close call sometimes. But Bloom's comment was not a close call - it was egregiously and deliberately offensive. One doesn't, for one thing, use a variation of a person's first name when one is mostly arguing against them.

Sorry, I'm Canadian.

The right way to show contempt is arch sarcasm, not childish whining. If Bloom wants his comments here, he can be restrained about it. If he wants a 100% pass, he should start his own blog. I might even read it. I sometimes read Fuller's too.

Tom said...

Glad to know I'm not the only dirty ex-hippie on this blog.

I don't want to be the cause or even the trigger for Steve Bloom's departure from this venue. Nor do I want the return of moderation. I find that I disagree with almost everything he says, but that's okay with me. And I can handle his snark--I just need to remember not to respond in kind.

Michael Tobis said...

Thanks. But I don't run flamewar sites.

Some might argue that I'm not an EX-hippie at all, but I hope I'm not dirty for all that.

Susan Anderson said...

Yes, and anyway those commie free love pinkos were all a myth. Very few of them were dirty, that was just namecalling. "Dirty" is just an epithet, like warmist.

mt, I think you are too young to have been a proper hippie.

I found Steve Bloom's content of value; his clarification of what I said (which was confused) was helpful, and his link outstanding. That's the difference, you see, no matter how amateurish I may be, I get help because the undertow of what I have to assume is dislike to the very premise is absent in my case.

Anyway, no problem with you running things as you please, but I was surprised and pleased to have his input here.

As for polite, some of the most effective delay and doubters are exceedingly polite. It's tactical. Also, they are very quick on the draw to accuse others of insult, while they freely distribute insults themselves. I agree it's a ClimateBall tactic:
“it’s easier to deflect toward concerns about tone and civility (two concepts that are too often confused) than to parry objections or answer questions”

EliRabett said...

Actually limiting warming to 2C was toast two or three ARs ago, but the importance of 2C is as a marker beyond which there be tygers.

Tom said...

We don't actually know that, do we? Because 2C is a political target and not a scientific one, we don't know if there's any difference at all between 1.75C and 2.25C. As most extrapolation of impacts jumps straight to the end game of 3C, 4C or worse, I at least have seen nothing more than an arrow chart to describe the effects of 2C.

I believe the Nordhaus (the one acceptable to your tribe) first bruited the 2C target because it captured the high end of temperatures in the history of modern humans. But the fact is that we don't know if sea level rise will accelerate starting at 2C as opposed to some other value. We don't know if the storms will get more intense at 2C, as opposed to some other value. Same is true for droughts, floods, heatwaves, etc.

The IPCC has collated some predictions for each of these, but they don't tie it to a particular temperature, preferring a BAU timeline which postulates their impinging on our welfare starting about 25 years from now.

I would love to read some papers on what happens at 2C. Citations welcome!