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4th National Climate Assessment report

Filed under: — gavin @ 23 November 2018

In possibly the biggest “Friday night news dump” in climate report history, the long awaited 4th National Climate Assessment (#NCA4) was released today (roughly two weeks earlier than everyone had been expecting).

The summaries and FAQ (pdf) are good, and the ClimateNexus briefing is worth reading too. The basic picture is utterly unsurprising, but the real interest in the NCA is the detailed work on vulnerabilities and sectorial impacts in 10 specific regions of the US. The writing teams for those sections include a whole raft of scientists and local stakeholders and so if you think climate reports are the same old, same old, it’s where you should go to read things you might not have seen before.

Obviously, since the report was only released at 2pm today without any serious embargo, most takes you will read today or tomorrow will be pretty superficial, but there should be more considered discussions over the next few days. Feel free to ask specific questions or bring up topics below.

103 Responses to “4th National Climate Assessment report”

  1. 1
    Steve Fitzpatrick says:

    All liks point at the same chapter: 18 Northeast.

    [Response: Sorry. Fixed. – gavin ]

  2. 2
    Gordon Cutler says:

    Thank you, Gavin! Alas, so far the links to Southeast and US Caribbean all lead to the Northeast pages. I haven’t checked the others yet.

    [Response: Sorry- fixed. Gavin]

  3. 3
    Tom Swartz says:

    Typos? The ten links listed under “Regional Chapters” are all pointing to the same page (that of the Northeast).

  4. 4
    Carrie says:

    Another very verbose report.

    “Further, it is beyond the scope of this chapter and this assessment to evaluate or recommend policy options.”

    So there’s no point in writing it at all. Another report to ignore forever. BAU to continue unabated.

  5. 5
    Mr. Know It All says:

    Interesting that in the Northern Great Plains, the map shows a change in number of days with greater than 1″ of rain will be between 0 and 1 day – not much change. Makes me wonder what the difference would be for lower rain amounts like 0.1″, 0.2″, 0.3″, etc.

    In the Overview on sea level change, Figure 1.4 shows that due to rising land in SE Alaska, the sea level change will be negative 5 or 6 feet by 2100! Land rising by 5 or 6 feet! Must be expecting more 1964 earthquakes.

  6. 6
    Aryt Alasti says:

    This is an incredibly comprehensive report. The section on sea-level rise for the northeastern states is sobering:

    Projections of Future Sea Level Rise and Coastal Flooding

    Projections for the region suggest that sea level rise in the Northeast will be greater than the global average of approximately 0.12 inches (3 mm) per year.247 ,248 According to Sweet et al. (2017),47 the more probable sea level rise scenarios—the Intermediate-Low and Intermediate scenarios from a recent federal interagency sea level rise report (App. 3: Data & Scenarios)—project sea level rise of 2 feet and 4.5 feet (0.6 m and 1.4 m) on average in the region by 2100, respectively.47 The worst-case and lowest-probability scenarios, however, project that sea levels in the region would rise upwards of 11 feet (3 m) on average by the end of the century.47 The higher projections for the region as compared with most others in the United States are due to continued changes in oceanic and atmospheric dynamics, thermal expansion, ice melt contributions from Greenland and Antarctica, and ongoing subsidence in the region due to tectonics and non-tectonic effects such as groundwater withdrawal.47 ,50 ,249 ,250 ,251 ,252 Furthermore, the strongest hurricanes are anticipated to become both more frequent and more intense in the future, with greater amounts of precipitation (Ch. 2: Climate, Box 2.5).50 ,253 ,254 ,255 Thirty-two percent of open-coast north and Mid-Atlantic beaches are predicted to overwash during an intense future nor’easter type storm,256 a number that increases to more than 80% during a Category 4 hurricane.257 ,258

  7. 7
    nigelj says:

    Carrie says “Another very verbose report.”

    Well yes its verbose, but only because it broke things down into a region by region analysis, which is actually rather useful for specific communities. Nobody has to read the whole thing.

    “Further, it is beyond the scope of this chapter and this assessment to evaluate or recommend policy options.”So there’s no point in writing it at all. Another report to ignore forever. BAU to continue unabated.”

    The report didn’t really need chapters on mitigation, because we already know the policy options in excruciating detail, and its not hard for local communities to adapt these to local conditions. We are currently going though this exercise.

    I don’t know that the reports can do much more than they do. The problem is obviously not a lack of information or clarity or statements of severity of risks.

    People are clearly still not motivated to make changes, people are self interested, governments are controlled by lobby groups, denialists keep spreading junk science, and humans are not programmed to react strongly to future threats. I mean its not looking too good right now.

    The research on hothouse earth should be read by everyone, because it really brings the scale of this disaster home, yet if we overdo the doom and gloom the public might switch off. I think more could be done to promote awareness of the benefits of renewable energy. Positive messages often lead to more change than negative messages.

  8. 8
    nigelj says:

    From the Guardian: “Climate report: Trump administration downplays warnings of looming disaster”

    “A White House spokeswoman, however, said the assessment was “largely based on the most extreme scenario, which contradicts long-established trends by assuming that, despite strong economic growth that would increase greenhouse gas emissions, there would be limited technology and innovation, and a rapidly expanding population.”

    “Katharine Hayhoe, a climate scientist at Texas Tech University and a report co-author, said the White House’s statement was “demonstrably false”.

    “She added on Twitter: “I wrote the climate scenarios chapter myself so I can confirm it considers ALL scenarios, from those where we go carbon negative before end of century to those where carbon emissions continue to rise.”

  9. 9
    Mr. Know It All says:

    4 – Carrie

    I also thought “another verbose report”. It just goes on and on and on with those huge paragraphs – even in the summaries and executive summaries. The color graphics do help visualize effects, but I’d like to see a few towns located in each state on those maps so I can pick the ones most and least favorable in the future.

    It would be good to have a list of bullet points covering the important information perhaps in the summaries and/or the executive summaries.

  10. 10
    steve says:

    An illuminating report, but sadly not produced by an organisation with any responsibility for introducing changes to bring about mitigation.
    What predictions for action resulting from its publication?
    Is it known if Russia and China produce similar assessments of the effect of climate change? And if so are they published for international consumption?

  11. 11
    Carrie says:

    #10 there’s a fair amount of info out there, just need to go looking for it. eg

    Shifting the climate change functions to the Ministry of Ecology and Environment gives the new Ministry a significant political mandate that provides an institutional guarantee for ecological civilization, green development, and a global community with shared future for humankind.

    Department of Climate Change

    PNAS – Paper/Artile
    Climate change, human impacts, and carbon sequestration in China
    Jingyun Fang, Guirui Yu, Lingli Liu, Shuijin Hu, and F. Stuart Chapin III
    PNAS April 17, 2018

    China’s Actions on Tackling Environmental Issues

    The importance of balancing economic growth with environmental protection, resource preservation, and CO2 emission mitigation is well recognized by the government, the academic community, and the public in China. The Chinese government has developed a series of policies and legislation to impede the trend of environmental deterioration (Lower graph in Fig. 1). For example, during the 2009 Copenhagen Accord Conference (16) China announced its intention to reduce CO2 emission intensity by 40–45% by 2020. During the 2015 Paris COP21, China released its voluntary emission-reduction targets for 2030 (17): (i) C emissions are set to peak around 2030, making best efforts to peak earlier; (ii) C emissions per unit of GDP will be reduced by 60–65% from the 2005 level; (iii) the share of nonfossil fuels in the primary energy consumption will be increased to 20%; and (iv) forest stocking volume will increase by 4.5 billion m3 [equivalent to 31.6% in C stock (18)] relative to the 2005 level. These emission-reduction targets, if achieved, will have far-reaching effects on China’s future climate-change policy, businesses, and industries, and may contribute significantly to mitigation of regional and global climate change (2).

    As an effort to implement its policies to slow down climate warming and to protect its environment, China has invested heavily and carried out several huge national ecological restoration projects, including the Natural Forest Protection Program, the Sloping Land Conversion Program, and the Desertification Combating Program around Beijing and Tianjin (Lower graph in Fig. 1). Meanwhile, local governments across the country have closed many energy-demanding but inefficient factories and businesses, and the Central Government has recently adopted a unified development strategy to curtail air pollution in the Beijing-Tianjin-Hebei region (the Pan-Beijing area). The implementation of these policies and practices responds both to pressure from the international community and to China’s need for environmental protection, public health, and ecological civilization (social–ecological sustainability).

    Environmental lawyer James Thornton says China’s ‘ecological civilisation’ concept is the best response to the world’s environmental crisis
    “Facing the ruin of their environment, the Chinese looked hard and amended their constitution. This core document now calls for the building of an ecological civilisation,” he says. “We built an agricultural, then an industrial, and now must build an ecological civilisation.”

    Unit 2 of the Sanmen nuclear power plant in China’s Zhejiang province has completed 168 hours of full-power continuous operation. The unit is now deemed to be the third AP1000 reactor to enter commercial operation.

    IV. Enhancing Food Security and Sustainable Agriculture in Response to Climate Change (APEC 2018)

    RU Enviro Ministry?

  12. 12


    Most Arctic areas are rising, due to isostatic readjustment post-glaciation. And no, there’s no connection with earthquakes AFAIK. The tectonic plates tilt more or less whole–which is why so many more southerly regions have lands that are sonking.

  13. 13
    Karsten V. Johansen says:

    Since these types of predictions rest upon unrealistic assumptions: that everything will continue gradually just as the hitherto recorded small effects of the growth in the CO2-level – which has in just hundred years been rolled back to the concentration level at least 26 million years ago ( ) – I think they are very misleading. They rest upon the “optimistic” bias and vulgar-economic dogmas of the ruling oiligarchy and it’s two-in-one-party de facto dictatorship. No researcher dare say anything contradicting these ruling castes and their ideologic dogmas. Only the brutal corrections of the reality will as always in human history bring the common consciousness in tune with what really is going on.

  14. 14
    S. Molnar says:

    I’m having a great time reading the report: I started with Chapter 18, since it seems to be so popular (OK, I live in the Northeast). The best part is the inclusion of so many references, which, alas, are often available only through subscription.

    I can’t help thinking the complaint that the report is “very verbose” is meant as a joke, since “verbose” is an absolute term – the phrase “very verbose” is, um, verbose.

  15. 15
    Carrie says:

    #14 maybe where you come from it is. otoh adjectives do apply in this case.

    Incomplete support for them leads to awkward designs, poor maintainability, and ‘painfully’ verbose code.

    Some of the ‘more’ verbose instances with obvious functionality have been left out for the sake of brevity.

    In other cases, the choice of unfamiliar and ‘sometimes’ verbose terminology appears to be descriptively motivated.
    [The opposite of ‘sometimes’ or ‘less’? Always or very or more? :-)]

    Of course, the constructions we have given are ‘too’ verbose to be of direct use in practice.

    In early attempts to rigorously follow the original design, calls to generic algorithms were ‘overly’ verbose.

    From Cambridge English Corpus

    And of course it was still stated ‘humorously’. The truth can also be funny. You’re welcome :-)

  16. 16
    Steven Emmerson says:

    Karsten V. Johansen@13 wrote

    No researcher dare say anything contradicting these ruling castes and their ideologic dogmas.

    Do you have references to the peer-reviewed, scientific literature that support this assertion?

  17. 17
    Ron R. says:

    Just read chapter 11, BUILT ENVIRONMENT, URBAN SYSTEMS, AND CITIES. I was dismayed to see the total energy put into describing the problem, out of control population and the excessive development resulting therefrom reduced to these few statements I culled from 11:m

    “Increasing urban populations pose challenges to planners and city managers as they seek to maintain and improve urban environments….Urbanization affects air, water, and soil quality and increases impervious surface cover (such as cement and asphalt)….Urban areas, where the majority of the U.S. population lives and most consumption occurs, are the source of approximately 80% of North American human-caused greenhouse gas (GHG) emissions, despite only occupying 1%–5% of the land….In recent years in the Southwest region, California experienced exceptional drought conditions. Urban and rural areas saw forced water reallocations and mandatory water-use reductions. Utilities had to cut back on electricity production from hydropower because of insufficient surface water flows and water in surface reservoirs.”

    The solutions offered are a mash of little bandaids while allowing the whole enterprise to continue:

    “Investment and design standards, professional education and licensing, building codes, and zoning that use forward-looking design can protect urban assets and limit investor risk exposure….City governments use a variety of policy mechanisms to achieve adaptation and mitigation goals. They adopt building codes, prioritize green purchasing, enact energy conservation measures, modify zoning, and buy out properties in floodplains….Urban mitigation actions include acquiring high-performance vehicle fleets and constructing energy efficient buildings.”

    There is this rather weak admission:

    “Not all plans address weightier concerns, tradeoffs, behaviors, and values. For example, coastal cities at risk from sea level rise may be constructing storm surge protections, but not discussing the possibility of eventual relocation or retreat (Ch. 8: Coastal, KM 3).59 ,131 Increasing tree canopy and planting vegetation to manage storm water and provide cooling can increase water use, which may present difficulties for water-strapped cities.”

    Yet in figure 11.1 it projects the population in just the Los Angeles region alone to be between 45,000,000 – and 90,000,000 people by 2100 (which has now swallowed up larger areas of the state)! Sorry, but unless we address the bigger issue, fixing these many small cracks in the dam is just going to be a Pyrrhic victory Sisyphusian style.

  18. 18
    Carrie says:

    I agree with #17 Ron R. says: Just read chapter 11, BUILT ENVIRONMENT, URBAN SYSTEMS, AND CITIES. I was dismayed to see the total energy put into describing the problem …

    Ah yes, but so long as they did not use fossil fuel energy, we’re sweet!

    The bureaucratic double-speak report reminds me of Sir Humphrey’s system for stalling.

    Stage One: Humphrey will say that the administration is in its early months and there’s an awful lot of other things to get on with.

    Stage Two: If I persist past Stage One, he’ll say that he quite appreciates the intention, something certainly ought to be done — but is this the right way to achieve it?

    Stage Three: If I’m still undeterred he will shift his ground from how I do it to when I do it, i.e. ‘Minister, this is not the time, for all sorts of reasons.’

    Stage Four: Lots of Ministers settle for Stage Three according to Tom. But if not, he will then say that the policy has run into difficulties — technical, political and/or legal. (Legal difficulties are best because they can be made totally incomprehensible and can go on for ever.)

    Stage Five: Finally, because the first four stages have taken up to three years, the last stage is to say that ‘we’re getting rather near to the run-up to the next general election — so we can’t be sure of getting the policy through’.

    … He also warned me of the ‘Three Varieties of Civil Service Silence’, which would be Humphrey’s last resort if completely cornered:

    1 The silence when they do not want to tell you the facts: Discreet Silence.

    2 The silence when they do not intend to take any action: Stubborn Silence.

    3 The silence when you catch them out and they haven’t a leg to stand on. They imply that they could vindicate themselves completely if only they were free to tell all, but they are too honourable to do so: Courageous Silence.

    (The Complete Yes Minister, pp. 93-4)

  19. 19
    Ron R. says:

    Correction. I see where population is touched upon in chapter 17. A few quick uses of the word, population, and these two statements:

    For example, rapid population growth in the coastal United States over the past half-century has significantly increased society’s exposure to extreme weather events like hurricanes….California faces an increasing population, deteriorating infrastructure, and potential energy and water resource limits for an agricultural sector that is evolving to depend on declining groundwater aquifers.

    Referencing these is the statement in the About This Report section:

    further guidance on U.S. population and land-use assumptions was provided to authors. See Appendix 3: Data Tools and Scenario Products, including Table A3.1, for additional detail on these scenario products.

    Come on. Can’t we do better than this?

  20. 20
    Ron R. says:

    #18 – exactly. It’s kind of strange because while population is so clearly the core issue with not just AGW, but all of our other environment problems, trying to get people, often the same people who are so well acquainted with denialism when it comes to climate change to care about population is like talking to a kid who rolls his eyes when you stress the importance of not smoking. “Oh brother” he yawns, “Here we go again!”

    The report, or at least those parts I read, reads like an encyclopedia, a haphazard smattering of little fixes, plugs in the dam (or maybe it’s the hull of the Titanic, while we steam toward the iceberg) just trying to make sure that everyone’s particular interest area is stuck in there somewhere. But where’s the urgency? It’s like the brain numbing minutes of the local city council meeting. Section 2.1: Install a stop sign at 13th and Grand.

    Example of the disconnect here, while we often stress climate change in relation to water scarcity issues (and, btw, just where are those 45-90 million angelinos going to get their water anyway?), why aren’t we mentioning population? We are so, sooo over our natural carrying capacity in California, not to mention the planet, that I half expect a crash if the rains just stop, yet we continue to build like there’s no tomorrow. I’m mean, WTF? I just don’t get it.

    IOW, we need a big national and international informational push, from heads of state on down, like we did and continue to do with CC, addressing population, explaining where we’re headed off we do nothing. And make no mistake, the enemies of population control are just as dedicated to stopping it as CC denialists are. They’re pretty much the same interests, profits at all costs.

    Anyway, my apologies. I really hate trashing this notable work. I know that so much went into it. But I have to be honest.

  21. 21
    Ron R. says:

    On a personal level, I want to be clear about something. For me, this is not about misanthopy, (though at times I suspect we all flirt with it, the world being what it is). Despite what opponents of population control insist, it’s not about draconian solutions (a few idiot comments by worried past notables excluded).

    It’s actually about loving and trying to preserve the good in the human race and our reason for being, and wanting the best for future generations – a happy life, not a wasted world. Yet not just for people, but for all of the other species that share, and have a perfect right to share, this still beautiful world with us.

  22. 22
    zebra says:

    Ron R,


    The problem, Ron, is that neither the demographic transition nor the energy transition is promoted by the kind of hair-on-fire, politically and sociologically naive, emotional ranting that is provided by you and others.

    There is no magic. There will be serious disruption, suffering, death… certainly by natural causes like drought and famine and fires, and probably by warfare, at least locally, but possibly on a larger scale. What we can do about it is to reduce those negative consequences on as rapid a realistic timeline as possible.

    While you seem sincere about this, I have observed– over decades now, I guess– that there are these favorite rhetorical/propaganda memes that show up when discussing climate: “Why don’t the liberals talk about the third world population explosion.”, and “Why don’t the liberals talk about nuclear power.”, and various other “gotcha” type ploys.

    Now, people on RC know that I have tried to bring up population multiple times, to no avail, so I think I have the credentials to pose the same question to you that I ask them:

    OK, what’s your plan?

    We know, with scientific certainty, what factors affect fertility. Women with economic security who are not dis-empowered by religious/social male dominated hierarchies choose to have fewer children.

    In the last US presidential election, one of the candidates had a history of working on women’s rights internationally and in the US, and expanding economic opportunity through trade and so on. Also, of course, expanding things like renewable energy in the US and I believe elsewhere. But, some here, and perhaps you, seem to think that wasn’t enough.

    So, if you were running for President, what would you run on? How would you accelerate the demographic transition, beyond putting resources into the established (and currently being decimated) channels?

  23. 23
    Tom Adams says:

    I don’t fully understand what they are saying about the economy. It seems that the use of GNP in the reports is odd or obscure.

    They seem to be projecting a relative decline in GNP of about 10% by 2100. Relative to what alternative future? GNP is a yearly rate, are they just saying the rate will be 10% lower than it would have been in 2100 relative to some alternative? Note that that is consistent with a good economy even if it is not a per capita number. I think they are perhaps using per capita GNP, but not sure.

    Sometimes they compare GNP to the destruction of property or capital. But that is just using GNP as if it were a denomination of the US currency, just an odd way to say “X billion dollars”.

  24. 24
    Ron R. says:

    Zebra. Thanks, I guess. Well, there’s actually two separate undertakings here, 1. As I suggested, we need to begin a serious dialog along the same emphasis as we give climate change. This is serious. It needs to be discussed, planned, hashed out with the same attention we’ve given CC. Right now it’s just a study and a few news articles every now and then. Then it’ s quickly forgotten. A few groups. CC has a lot of push behind it at every level. Everyone’s talking about it, which is great. Population is the elephant in the room that almost everyone pretends isn’t there. So we need the same emphasis, from here at Real Climate, to a serious working group, from the president, congress etc. on down. In every country. On every level. First acknowledge that population is a wall we’re racing toward. Acknowledge that it’s a problem. But this time, unlike with CC, don’t let the denialists hijack and delay.

    The second question, what would I do if I had the ability? First, listen to what people, especially biologists, are saying, what conclusions they are reaching after all this discussion. Then implement the best ideas. Personally, I like the idea of paying women not to procreate, or try to keep thing below the replacement/attrition level. Discover what the optimum human population should be and work towards that. I’ve heard one billion, but it’s open. Restructure our aggressive pro-growth economy. Etc. But before we can do that, begin the talk.

  25. 25
    Carrie says:

    OK so let us review recent events in view of the CLIMATE CHANGE Reports that have been published most recently by THE EXPERTS.

    We now have the US 4th National Climate Assessment (#NCA4)

    Not that long ago we we handed the IPCC Global Warming of 1.5 °C Report

    The Club of Rome in November put out this new Report

    And now we have this latest news report
    Countries vowed to cut carbon emissions. They aren’t even close to their goals, U.N. report finds
    A new ‘emissions gap’ report says we’re even further from where we need to be than we thought. by Chris Rooney

    about this latest UN Emissions Gap Report 2018
    27 November 2018
    Authors: UN Environment

    What could all this mean? Please would someone here be able to read all these and summarize the important take-away messages?

    I am off to the tattoo artist, wil be back soon. I am getting FUT tattooed on my left hand and URE tattooed on my right. This way the Future is always in my hands which will remind me how incredibly powerful I am in driving change in AGW/CC policy and mitigation actions globally.

    Hopefully the above intelligent reports wil tell what actions to take whne I get home. TY

  26. 26
    Ron R. says:

    Got distracted there.

    Another thing for discussion is encouraging western families to stay together if possible, like they do in Asian countries like Japan where space is at a premium. The point being to reduce construction of new homes and all the stuff that people need to fill them with. You might call it “house pooling”, ala carpooling. I mention this a few months ago.

    I truly believe, hope, that with enough attention things might begin to turn around. As they do, and the our red hot population begins to cool down, perhaps we could restructure the economy around deconstruction, i.e. actually tearing down and recycling buildings, cities etc. etc. Take a look at this short story.

    Anyway, these are just ideas, but are the kinds of discussions we need to have, and soon.

  27. 27
    David Young says:

    Tom, I wouldn’t take the 10% of GDP number seriously. I apparently assumes a 15 degree F temperature increase vastly more than reasonable TCR’s give for RCP 8.5 which itself is probably unattainable. For other RCPs the numbers are less than about 2%. One has to question why this scenario was used in the report.

  28. 28
  29. 29
    Karsten Vedel Johansen says:

    Re #16 Steven Emmerson: of course I did put it very harsh. It’s in the nature of self-censorship that it is difficult to prove that it goes on. But reading and listening to the political statements from official institutions like the IPCC through the years since Hansen came with his warnings 1988, it is obvious that they mainly keep repeating the same all the time: “The time to act is now” etc. The clock is always five minutes to midnight in their rhetoric (the “Summary for policymakers” should rather be named “Summary *by* policymakers”), regardless of the situation which has developed according to the BAU scenario (actually business as extremely usual…) for now thirty years, completely unaffected by the scientific warnings. As documented by Wally Broecker, the amount of renewable energy relative to fossil energy used globally is still just about the same as it was in the seventies: 15/85.

    But who in their right mind can expect “the common man” to take the scientific warnings seriously, as long as no political leadership does (with the good exception of the canadian government which has declared just about a week ago that they will implement Jim Hansen’s “carbon fee and dividend” model throughout the whole of Canada). Especially when most scientists just go on repeating the same warnings even when the carbon dioxide emissions are just exploding on and on.

  30. 30
    Ron R, says:

    Thanks Mr. KIA.

  31. 31
    Gkoehler says:

    I don’t understand the 10% GDP impact estimate by 2100 under RCP8.5. If we stayed on RCP8.5 emissions trajectory out to 2100, global average surface air temperature increase would be over 4C. World Bank, Kevin Anderson, and others have estimated that the 4C is “incompatible with an organized global community”, i.e. modern human civilization. At +4C we wouldn’t have a slightly reduced GDP, we would be living in a Somalia-Libya-Syria-Yemen like failed state scenario on a global scale. Think collapse of Soviet Union x 10 or 2008 financial crisis x 10 and you might be getting close. Think Mad Max.

    If we don’t have a habitable climate, we don’t have a functional global economy, at least not the tightly interconnected version we have now. So how does staying on RCP8.5 until 2100 allow retaining anywhere close to 90% of a no-climate-change GDP?

    I think economists report on what they can measure. But apparently they can’t measure a nonlinear, interconnected, systemic crash, which is where RCP8.5 takes us.

    Paul Krugman NYT editorial calls climate change deniers “depraved”. Indeed they are. How does the continued existence of human civilization not meet the requirement for a moral imperative? Even Republican politicians must love their kids. Does their magical thinking convince them that their loved ones are immune? Do they have any concept of truth vs. lies?

    Apparently the Depraved Lunatic in Chief does not. Don’t think of him as stupid. That may or may not be an act. I doubt he can really be that oblivious to objective reality. That leaves me with a more sobering view. He is simply evil incarnate. Realizing that gives a new impetus to how one views and resists Trump Admin. assaults on democracy, decency, and humanity.

  32. 32
    nigelj says:

    Ron R

    I agree population pressure is a huge environmental problem. Fortunately the demographic transition has already lead to a drop in fertility in western countries, some already below replacement rates, but you have to be careful, because if the curve bends down too much you end up with a demographic bulge of dependent elderly people of epic proportions.

    Getting population growth down obviously won’t do much to stop temperatures getting to 2 degrees, but it could help stop them escalating further towards 5 degrees or more given the time frames and realistic policy options.

    In developing countries birth rates are still high. Conventional wisdom says the demographic transition of increasing wealth and better womens rights will eventually drive rates down and they will, however these are not essential preconditions. Some African countries have given away free contraception or made it easily available, that has lead to a steep drop in birth rates despite poverty and women having limited rights. The crucial factor is having easily available contraception and reasonable basic health care. The did an article on it. (In no way am I excusing some of the appalling treatment of women)

    Having some form of tax incentive might help, and I think better education on the benefits of smaller families would go a long way and costs little. Its a political issue. Governments are shy of taking on the issue for obvious reasons. Lobby your local politicians.

  33. 33
    Marco says:

    David Young,

    Consider how credible that 2% for the other scenarios is, when 8 degrees (Celsius) supposedly only causes 10% loss of GDP. 8 degrees. In a wide band around the equator, 8 degrees increase is likely incompatibly with human civilization.

    Also, good luck trying to live in the south of the US with 8+ degrees higher temperatures.

  34. 34
    zebra says:

    #24 Ron R,

    So you are going to run for USA president on a platform that includes “paying women not to have children”. Got it. Could you flesh that out a little? Just a ballpark monetary figure, to begin with. And, you know, which women?

    Oh, and from which party, D or R, do you expect to get enthusiastic support?

    And to think I suggested that you were being politically and sociologically naive…

    Ron, I repeat that you seem to be sincere in your concern for the future of humanity, but you illustrate my point about the convergence of some ideas from “our side” with what the right-wing trolls use as poison-pill, false-flag rhetorical ploys.

  35. 35

    David Young, #28–

    I[t] apparently assumes a 15 degree F temperature increase vastly more than reasonable TCR’s give for RCP 8.5 which itself is probably unattainable.

    Just off the top of my head, I have a couple of thoughts. First, NCA 4 is concerned primarily with impacts, right? So that means, first and foremost, temperatures on land specifically. And while RCP 8.5 does indeed have a high GMST projection of about 5 C, which is 9 F, you can basically double that for warming over land. So now you are talking about 18 F, and that’s before you consider that the US includes Alaska, which will see yet more warming. So at this point I can’t agree with you that the number is ‘vastly more’ than plausible.

    Second, you state as if it were fact that the RCP 8.5 scenario is “probably unattainable”. Well, I’d sure love it if that were the case, but on what evidence do you say that? It’s my understanding that a) current emissions are most closely approximating the 8.5 trajectory, and b) higher climate sensitivities remain quite possible given the current state of the art.

    True, I think along with many others that there will be an increasing degree of emissions mitigation going forward, which will help–but it still seems to me that given the current numbers, it’s far from a given that we won’t end up approximating the 8.5 trajectory.

    Going beyond the quoted statement, I agree that the 10% figure should ‘not be taken too seriously’–because I suspect that the reality will include non-linear effects which currently are impossible to quantify–for instance, along the lines of AR4, in which no estimate of dynamic glacial ice loss was given because there was insufficient basis of quantification–as well as non-linear effects which are at present completely unanticipated. (For instance, I don’t think anyone anticipated the increase in blocking events now being investigated as a possible consequence of sea ice loss.)

    IOW, I think the reality could just as well turn out *worse* than 10%, as it could ‘less bad.’

  36. 36

    Karsten, #29–

    Canada’s change of heart is a good thing, but don’t get too enthused; the political tradeoff was essentially the federal government building a pipeline to export Canadian tarsands heavy oil, which is a pretty big ‘lock-in’ of future emissions.

    On a more cheerful note, Canada isn’t the only jurisdiction doing something of the sort:

    (That page, though useful, could stand an update.)

  37. 37

    In the continuing absence of a Forced Variations thread, perhaps it’s at least relevant to note this Australian straw in the wind:

    “I sat there on polling booths and every second person either gave you deadly silence, which is a very cold, deadly silence, or there were people mentioning energy, climate, or the deposing of the prime minister,” said Victorian Liberal MP Tim Wilson, speaking to Sky News.

    The prime minister, of course, having doubled down on Liberal (ie., conservative) support for fossil fuels and climate obstructionism…

    To be clear, this was a state election in Victoria–but the question is, what does it portend for the upcoming Federal election?

  38. 38
    MA Rodger says:

    Karsten Vedel Johansen @29,
    I’m not sure that I’d go along with either the “15/85” ratio or the “always five minutes to midnight” messaging.

    On the 15/85 ratio, the Broecker quote is not that this ratio of renewables-&-nuclear/fossil-fuel-use has not changed since the seventies. Rather the quote concerned a longer period:-

    “In 1950s, when I was in graduate school, we got 15 percent of our energy from renewables and nuclear, and 85 percent from fossil fuels. Today it’s the same. Both of them have been increasing at 3 percent a year.”

    The quote was (and thus also “today” was) from 2017.
    Now this 1950s/2017 comparison may or may not be correct but it does not hold true through the period. And further, it hides some very significant information.
    The BP 2017 Statistical Review of World Energy gives data back to 1965 which shows nuclear-&-renewables were 6% of primary energy use in 1965 and back then overwhelmingly comprised hydro-electric. In the period to 2017, hydro remained roughly as a constant percentage with nuclear rising up to 6% by 2000 and since falling back to 4½%. The 2017 level total is 15% with ‘other renewables’ contributing 3½%. This last figure has risen greating in recent years, less than 1% in 2007, less than 2% in 2012, less than 3% in 2015 and likely to top 4% this year. With such a growth rate, we can expect it to make big inroads into fossil-fuel-use in coming years.
    Thus I do not see in this anything as black as that painted by Broecker’s quote.

    The constant message through the decades that there is need for immediate action to mitigate AGW is perhaps true but the proposed mitigation has had the same target date for these decades with the requirement becoming stronger with time – reduction to 50% of 1985 emissions by 2050 in FAR now being 100% reduction by 2050 in AR5.

  39. 39
    Hank Roberts says:

    A snippit from oneof myemai notices:

    E&E Daily
    Thursday, November 29, 2018

    Global warming enters infrastructure talks
    Maxine Joselow, E&E News reporter
    As momentum builds for an infrastructure deal in the next Congress, a major new report is thrusting climate change into infrastructure talks on Capitol Hill.

    The second volume of the National Climate Assessment, a sweeping report produced by 13 federal agencies, warns that the lives and safety of Americans are already being harmed by climate change (Climatewire, Nov. 23).

    The document came after leaders of both parties have signaled a willingness to collaborate on broad infrastructure legislation in the next Congress (E&E News PM, Nov. 7).

    Climate change has largely been absent from those discussions. But during a hearing yesterday on surface transportation infrastructure, Democrats on the Senate Environment and Public Works Committee repeatedly highlighted the report and the need to account for a warming planet.

    “We cannot have a conversation about surface transportation without talking about climate change and the increasingly extreme weather that accompanies it,” ranking member Tom Carper (D-Del.) said in his opening statement.

    “Our transportation sector is a major contributor to climate change, and our roads, bridges, and railways are also extremely vulnerable to the effects of extreme weather fueled by climate change,” Carper said, citing the assessment’s findings.

    “Our next infrastructure bill must respond to this threat by focusing on a more resilient and sustainable transportation sector to protect communities nationwide,” he added….

  40. 40
    Ron R. says:

    Zebra, I’m saying that the reason the population has grown so out of control is because, like CC, the great majority of us haven’t thought it was a problem, or at least, not that serious a one. And the reason for that is because no one (with the exception of a few lone voices) has been talking about it. There’s no sense of urgency. No head of state discussing it. Rather, the topic has been assigned a sense of nuttiness by those who want to keep distance between the science and the voters, making it a classic example of kicking the can, and the consequences, down the road.

    Yet, imo, we’re already well past the time when we should have had our discussions and deep into the period when we should have been implementing the solutions.

    To recap:

    “It took all of human history up to 1804 for the world’s population to reach 1 billion. But the next billion came only 100 years later, in 1927. And after that, the rate of growth accelerated, 3 billion in 1959, 4 billion 1974, 5 billion 1987, 6 billion 1999, and now 7 billion. We’re adding a billion population every 12 years.”


    “There is an 80% probability that world population, now 7.2 billion people [nope, now more than 7.5 billion], will increase to between 9.6 billion and 12.3 billion in 2100.”

    If that doesn’t seem like enough of an emergency to people then there’s nothing more to be said, and I suppose we’ll just let the chips fall where they may.

    The FNCA mentions “Quality of life” many – times, but really, what kind of quality of life will there be for humans in a vastly over populated world? Or are we going for the Easter Island challenge? I mean, sometimes it seems like the objective of some is to see just how many people we can cram onto this small planet. I have to ask, why? Why aren’t we talking limits?

    The pro-growthers say that all we gotta do is wait for China and India and the rest of the world to catch up to an American standard of living then we’ll just all naturally back off on the procreation. But anyone who’s been paying attention knows that Earth is already well over extended, thus any such growth will likely mean the end of the biosphere as we’ve known it.

    On the other hand, if world population were much less, then yes, all likely could enjoy a better standard of living, without it meaning ecocide.

    To me it’s pretty selfish and shortsighted to be toying with how many people we can get on the earth when most of earth’s other species are losing ground because of it. Many of the most enigmatic now number in the mere hundreds or thousands. Half are projected to vanish in a hundred years. Is a denuded planet really, reallythe kind of world we want to live on?

    A good primer would be to familiarize ourselves with the works of Hopfenberg & Pimentel.

  41. 41
    Al Bundy says:

    Ron R: We are so, sooo over our natural carrying capacity in California,

    AB: Not even close. California suffers from an excess of agriculture. The people of California use very little water.

    They also suffer from a land management system that doesn’t work in the new climate.

    But there’s plenty of space and plenty of water in California for people. (It’s those almonds that are the problem)

  42. 42
    Karsten V. Johansen says:

    Re MA Roger # 38: You are probably right. But the amount of non-fossil energy used is still absurdly low. Most of it is still burning of wood in mostly very poor countries, ie burning down rainforests etc.

    My main point here is this: as long as we have an energy market, the price of energy will go down when we add more energy, regardless of it being fossil or non-fossil. Thus energy consumption will continue to rise exponentially. Unless we introduce a rising tax on the fossil fuels nothing significant will change except for the atmospheric CO2 level to continue upward from now the situation 26 million years ago in the early Oligocene backwards toward the PETM world 55 million years BP at a breathtaking pace.

    As Gkoehler # 31 wrote: the result will rather soon be global economic collapse. The absurdity of the IPCC language is talking as if any change in the global systems will always be gradual and manageable by something like the mainstream illusionary politics of today. But of course you can’t expect anything but this kind of language from a body hopelessly dictated by our current oiligarchy puppets, be they trumpist open climate ignorants or clintonic/bushic more closet ignorants/lukewarming fake and for IPCC “pure bullshit” as Jim Hansen correctly calls this. “The time to act is now” etc. is the pseudopolitics of “ideal political zero-messages” as the german writer Hans Magnus Enzensberger called this 1983 in a famous essay. Since then this kind of liberal nonsense has brought the world exactly nowhere but back toward the age of protofascism and stalinism just before the second world war with the supplement of ecologic desaster.

    In this hopeless situation the Canadian implementation of carbon fee and dividend is so far the only glimmer of light in politics. Even if small. Traditional carbon taxing like France/Macron now is trying just makes the small people go ape because they can’t afford to buy new electric cars etc. It makes them vote for the trumpists and it won’t do any good to try to pin that on Putin by conspiranoic neomccarthyist nonsense like the clintoniacs are doing all the time. The huge advantage of the carbon fee and dividend model is that it makes carbon taxing socially right: the expenses will owerwhelmingly be paid by the rich. The Canadian model is too vague but still it is a start at least. An implementation of it in the US and the EU would equal a global revolution in energy and climate politics. Soon China and Russia etc. would be forced to follow suit. And Trump and brazilian fascism, saudi feudalism etc. would be history.

  43. 43
    Ron R. says:

    Zebra, just reread your posts. I’m engaged in “hair-on-fire, politically and sociologically naive, emotional ranting”. Fine. Undoubtedly one can fault with any and all of my ideas. What are yours?

    You’ll note that I’ve mentioned several times that “we need a big national and international informational push”. To start a discussion, and that everyone, especially scientists, and of them, especially biologists, should be involved so we can develop ideas, then move quickly to act on the best of them. I never said that I want to ‘be president’ and make unilateral decisions Trump style. You said that. I’m not claiming to have all of the answers. I’m just one guy. On another thread I even suggested we use AI to help figure these tough, thorny issues out since none of them (with the possible exception of the ozone) are resolving to date, and in fact are getting worse. Do you see a pattern here? It’s not about me. It’s about us figuring this thing out. The crux of the problem.

    But, again, to do that it has to be seriously addressed, over and over and over again if necessary, in every country, just like CC has been, by everyone with any influence until it’s as embedded in our consciousness as CC is. My hope is that by raising the issue it will raise awareness. Sure a lot has been written about population, yet it’s just a drop in the bucket compared to CC. There’s a whole new generation out there. If they don’t hear that there’s a problem, they won’t know it, right?

    Still, maybe you’re right and it’s hopeless (if that’s what you’re saying). What’s sure though is that nothing will be accomplished if all we do is decend into petty RC style of excruciatingly endless ad hominem argument, which I have no desire to be a part of. I think I’ve made my point though, so I’ll move on.

    Anyway, it’d been a pretty sad thing if we allow millions, even billions of years of evolution, all that earthly beauty, to come to nothing.

  44. 44
    Mr. Know It All says:

    40 – Ron R
    “No head of state discussing it.”

    I agree that our population is out of control, but it has not only been discussed, but China had a strict 1 baby policy. I think they’ve abandoned that. Find out why – it might be instructive. Believe it or not many people believe Bible teachings like “Go forth and multiply”. You may not believe it, but many folks do, and I’d bet there are similar teachings in other religions. You cannot simply toss out beliefs of others just because you want to – they have rights too, correct?

    31 – Gkoehler
    “Apparently the Depraved Lunatic in Chief does not. …. He is simply evil incarnate……” and
    “Paul Krugman NYT editorial calls climate change deniers “depraved”. Indeed they are.”

    Does this guy sound depraved and like evil incarnate, or like a decent man who would just like to see his country treated better?

    Belive it or not, many people just do not believe in CC. 99% of those who do believe have little or no concept of how it works. Why would people not believe it? Well, for starters it was pushed by Gore – a leftist, and a lot of folks don’t care for leftists. Recently, leftism has shown an ugly side that is becoming increasingly unpopular in the US and in Europe, even among those who DO believe in CC. Another reason folks don’t believe is that noone can find an understandable, concise description of the science and math behind CC. And, there is “proven” evidence that the world has been warming for far longer than we’ve burned FFs – for example, why, they will ask, did the ice ages happen, then recede, over and over? Legit question, right? So, Krugman is an idiot – people are not depraved, they have legitimate questions about CC, and are not going to blindly follow idiot leftists without knowing why. So, calm down, and get to work trying to solve the problem instead of just calling people names. ;)

  45. 45

    Ron R, #40–

    The pro-growthers say that all we gotta do is wait for China and India and the rest of the world to catch up to an American standard of living then we’ll just all naturally back off on the procreation.

    I agree with many of the perspectives in your comment, Ron, but it seems to me that the picture isn’t quite what you are presenting.

    First and most notably, China ain’t the problem when it comes to growth. Between the one-child policy and rapid development, they’ve been well below replacement fertility level for a long time. But there is tremendous inertia in population, and in particular in age structure, so ‘peak China’ is expected around 2035:

    India is more problematic, and is expected to overtake China as the world’s most populous nation. On this site, looks like that is projected for sometime between 2020 and 2050:

    But even at that, India’s fertility rates have dropped tremendously, and are now approaching replacement level. (Specifically, the current rate given is 2.41, whereas replacement level is usually considered to be around 2.1. For context, India’s rate prior to 1970 was ~5.9).

    The real hotspots for fertility today are pretty much all in sub-Saharan Africa. The highest rate anywhere today is in Niger, at around 7. See figures 6A & B in this study (which looks to me to be darn rigorous):

    Second, it’s not really about ‘standard of living’; it’s about public health (especially as it affects child mortality and security in old age) and about the empowerment of women. Those developing countries in 6A & B with sub- or near-replacement level TFRs don’t have the standard of living seen in the OECD.

    So am I saying “don’t worry about population growth?” No. It’s problematic for all the reasons that you and others have laid out already in this thread–and particularly so in combination with the imperative for economic development, which is strong around the world, and which is not going to go away any time soon. So we need to support efforts to bring down birthrates, especially where they remain very high.

    But population is a very difficult variable to manipulate in the real world, except by massive increases in death rates. To put it bluntly, population can’t be reduced quickly enough to solve the climate crisis, except by genocide on a scale that’s nearly unimaginable (and is certainly unacceptable to everybody but perhaps a few psychopaths). So population control, though important, is not the key to surviving the climate crisis.

    It is, however, one of the keys to longer-term sustainability.

  46. 46
    zebra says:

    #40 Ron R,

    You complained that nobody wants to discuss population, which you said is a really important problem.

    I said, I agree completely, lets have a discussion about what policies we could get the government to implement to help reduce population.

    But you apparently don’t want to actually discuss solving the problem.

    As soon as I expressed some doubt about your proposal to “pay women not to have children”, you just repeated your original statement that “population is a big problem but nobody wants to discuss it.”

    Sorry, but again, that’s exactly what the trolls do whenever I respond to them in some comments section about climate somewhere. They don’t want to solve the problem, they just want to create a distraction.

  47. 47
    Matthew R Marler says:

    39 Hank Roberts: “Our next infrastructure bill must respond to this threat by focusing on a more resilient and sustainable transportation sector to protect communities nationwide,” he added….

    It would be improvement if they would plan for the past, let alone a modeled future.

  48. 48
    NobodySpecial says:


    A small quible: “First and most notably, China ain’t the problem when it comes to growth. Between the one-child policy …”

    China’s one-child policy began phasing out in 2016. Even discounting latent growth, China has and will have 1.3 billion people, all of whom want televisions, cars, meat and larger housing. Family status in China and many advantages/disadvantages depend on perceived wealth, and they will not settle for lite, minimal or in any way inferior versions of these things. Considering that pretty much everything is manufactured in China, they won’t have to.

    China appears to intend to become the global source in PV, wind and battery sectors and -may- limit their citizen’s fossil fuel consumption. They may also use their creditor position to essentially colonize and own Venezuela. VZ has the world’s largest petroleum reserves.

    I’m not arguing with your points, they’re pretty much undeniable.

  49. 49
    Ron R. says:

    Al Buddy, #41: Ron R: We are so, sooo over our natural carrying capacity in California,

    AB: Not even close…there’s plenty of space and plenty of water in California for people

    Oh, I’d agree with you 100%. There’s lots more land and resources left that we can use. All available for the taking (and we are). Problem is, we happen to share this world with 10,000,000 or so other species which not only also< have a right to exist and to live the lives they evolved to live, but a biosphere, or ecosystem (all of which we, believe it or not, <em/need to survive – unless you think we should enact the Simon Solution and just shove all wildlife in zoos. Yes, we can grow. But where we’re at is already having profoundly negative effects on nature.

    Mr. KIA, #44. Genesis 1:28. I know. Problem is, we’re still going forth and multiplying as if the world were still empty.

    Kevin McKinney, #45. Good points. And good news about China. Though like you say, there is tremendous inertia in population. Who knows what may change between now and then. Certain factors, such as a general feeling of insecurity seem make the population rise. Reassuring population projections are nice, but we shouldn’t be lulled into a false sense of complacency by those who would use such projections to create apathy and delay. Let’s also not forget the findings of Hopfenberg & Pimentel that as long as resources are available the population will grow. The rate may slow, but it’s still up. Thus, like the campaign against smoking,

    (and discounting genocide or natural tragedy), probably the only way we’re going to make progress on the issue is with a concerted campaign of education at every level, from grade school on. Can we apply the Law of Inertia here: objects will maintain their state of motion unless acted upon an outside force? You also say, So we need to support efforts to bring down birthrates, especially where they remain very high.. Just what I’ve been saying (or trying to say). One part of that might be at least a chapter inclusion the 5th National Climate Assessment.

  50. 50
    nnoxks says:

    A 10% reduction in GDP for a 15F rise? Isn’t that about 7C? That seems optimistic. How did they make that estimate?