Real Adaptation Is As Politically Tough As Mitigation, But Much More Expensive And Less Effective At Reducing Future Misery

Posted on

"Real Adaptation Is As Politically Tough As Mitigation, But Much More Expensive And Less Effective At Reducing Future Misery"

Rhetorical adaptation, however, is a political winner. Too bad it means preventable suffering for billions.

We basically have three choices: mitigation, adaptation and suffering. We’re going to do some of each. The question is what the mix is going to be. The more mitigation we do, the less adaptation will be required and the less suffering there will be.

Sandy Slams Atlantic City

That’s the pithiest expression I’ve seen on the subject of adaptation, via John Holdren, now science advisor.  Sometimes he uses “misery,” rather than “suffering.”

Frankenstorm Sandy, like Katrina, provides many lessons we continue to ignore, such as Global warming “adaptation” is a cruel euphemism — and prevention is far, far cheaper.

I draw a distinction between real adaptation, where one seriously proposes trying to prepare for what’s to come if we don’t do real mitigation (i.e. an 800 to 1000+ ppm world aka Hell and High Water) and rhetorical adaptation. The latter is a messaging strategy used by those who really don’t take global warming seriously — those who oppose serious mitigation and who don’t want to do bloody much of anything, but who don’t want to seem indifferent to the plight of humanity (aka poor people in other countries, who they think will be the only victims at some distant point in the future).

In practice, rhetorical adaptation really means “buck up, fend for yourself, walk it off.”  Let’s call the folks who push that “maladapters.”  Typically, people don’t spell out specifically where they stand on the scale from real to rhetorical.

I do understand that because mitigation is so politically difficult, people are naturally looking at other “strategies.”  But most of the discussion of adaptation in the media and blogosphere misses the key points:

  1. Real adaptation is substantially more expensive than mitigation (see Scientists find “net present value of climate change impacts” of $1240 TRILLION on current emissions path, making mitigation to under 450 ppm a must, reprinted below).
  2. Real adaptation without very substantial mitigation is just a cruel euphemism (see An Illustrated Guide to the Science of Global Warming Impacts).
  3. Real adaptation requires much bigger and far more intrusive government than mitigation.  Indeed, if the anti-science ideologues get their way and stop serious mitigation, then the government will inevitably get into the business of telling people where they can and can’t live (can’t let people keep rebuilding in the ever-spreading flood plains or the ever-enlarging areas threatened by sea level rise and Dust-Bowlification) and how they can live (sharp water curtailment in the SW DustBowl, for instance) and possibly what they can eat.  Conservative action against climate action now will force big government in coming decades to triage our major coastal cities — Key West and Galveston and probably New Orleans would be unsavable, but what about Miami and Houston?  (See Don’t believe in global warming? That’s not very conservative.)
  4. Real adaptation is so expensive (and endless) that it is essentially impossible to imagine how a real adaptation bill could pass Congress — unless of course you paid for it with a high and rising price for CO2.  Hmm.  Why didn’t somebody think of that?
  5. The only people who will pursue real adaptation are those who understand the latest science and are prepared to take serious political action based on that understanding. Unfortunately, that doesn’t include any of the people people who helped kill the climate bill back in 2009 and 2010.  There isn’t really much point in spending tens of billions of dollars to plan for, say, a sea level rise of several feet if you don’t accept that is what’s coming. The point is, you can’t even imagine doing the planning and bill-writing and then actually investing in real adaptation — unless  you accept the science  and do serious worst-case planning.  But if  you accepted the science, you’d obviously pursue mitigation as your primary strategy, while using some of the proceeds from the climate bill to support adaptation.

So real adaptation is not more politically viable than real mitigation — and arguably it’s less viable since at real mitigation has multiple co-benefits, including less urban air pollution, improved health and productivity, sharp reductions in oil imports and so on.

What really is the point of pursuing something that is not more politically viable than mitigation when it won’t actually prevent misery and suffering for billions of people?  Sure, we must pursue adaptation for Americans — and we are ethically bound to help developing countries adapt to the climate change that we helped create — but real mitigation is the sine qua non.

Real mitigation is an effort to keep emissions as far below 450 ppm as is possible — and if we go above 450 ppm, to get back to 350 as fast as possible (see How the world can stabilize at 350 to 450 ppm: The full global warming solution).

Let me expand on #1 and #2 below.

What is the cost of “adaptation”?  It is almost incalculable.  The word is a virtually meaningless euphemism in the context of catastrophic global warming.  Here is what dozens of recent studies make clear we risk if we stay anywhere near our current emissions path:

  • Staggeringly high temperature rise, especially over land — some 10°F (or more) over much of the United States
  • Permanent Dust Bowl conditions over the U.S. Southwest and many other regions around the globe that are heavily populated and/or heavily farmed.
  • Sea level rise of some 1 foot by 2050, then 4 to 6 feet (or more) by 2100, rising some 6 to 12 inches (or more) each decade thereafter
  • Massive species loss on land and sea — perhaps 50% or more of all biodiversity.
  • Much more extreme weather
  • Food insecurity — the increasing difficulty of feeding 7 billion, then 8 billion, and then 9 billion people in a world with an ever-worsening climate.
  • Myriad direct health impacts

No wonder climate expert Kevin Anderson (see here) has said inaction on climate change is “incompatible with organized global community, is likely to be beyond ‘adaptation’, is devastating to the majority of ecosystems & has a high probability of not being stable (i.e.  4°C [7F] would be an interim temperature on the way to a much higher equilibrium level).”

And 7F isn’t close to the worst case:

So what precisely do you plan for in your adaptation strategy?  You need to determine at some point whether you can save Miami, say, because you wouldn’t want to waste $100 billion trying only to find out you planned for the wrong scenario and it was hopeless.  Then again, who is going to get people out of their cities as long as one political party is devoted to shouting down anybody who claims humans are actually warming the planet?

And how exactly do Muscovites “adapt” to the possibility of 20°F Arctic warming?  What would a 1000-year heat-wave look like in 2100 if the planet is 9°F warmer?  How exactly would the world adapt to see levels 4 to 6 feet higher in 2100 and then rising 6 to 12 inches a decade?

Fundamentally, massive prevention plus lots of adaptation (and some misery) is much, much, much cheaper than not bloody much prevention and incomprehensible amounts of adaptation and suffering and misery.

And as the IIED reported in 2009, their study Assessing the costs of adaptation to climate change: a review of the UNFCCC and other recent estimates concludes costs will be even more when the full range of climate impacts on human activities is considered.

Scientists led by a former co-chair of the Intergovernmental Panel on Climate Change [warn] that the UN negotiations aimed at tackling climate change are based on substantial underestimates of what it will cost to adapt to its impacts.

The real costs of adaptation are likely to be 2-3 times greater than estimates made by the UN Framework Convention on Climate Change (UNFCCC), say Professor Martin Parry and colleagues in a new report published by the International Institute for Environment and Development [IIED].

The study finds that the mean “Net present value of climate change impacts” in the A2 scenario is $1240 TRILLION with no adaptation, but “only” $890 trillion with adaptation.

The mean [annual] impacts in 2060 are about $1.5 trillion”….  As usual, there is a long right tail, with a small probability of impacts as large as $20 trillion.

Don’t worry folks, it’s only a “small probability” (in their analysis) — but that “fat tail” by itself is enough to render all traditional economic analyses useless (see Harvard economist: Climate cost-benefit analyses are “unusually misleading,” warns colleagues “we may be deluding ourselves and others”).

Let’s put aside the fact we are on pace to exceed the A2 scenario (which is “only” about 850 ppm atmospheric concentrations of CO2 in 2100):  See U.S. media largely ignores latest warning from climate scientists: “Recent observations confirm … the worst-case IPCC scenario trajectories (or even worse) are being realised” — 1000 ppm.  For this country, the A2 scenario means 9 to 11°F warming over most of inland U.S. by 2090 with Kansas above 90°F some 120 days a year.

But here’s the key point the media and the authors failed to convey.  In the “aggressive abatement” case (450 ppm), the mean “Net present value [NPV] of climate change impacts” is only $410 trillion — or $275 trillion with adaptation.  So stabilizing at 450 ppm reduces NPV impacts by $615 to $830 trillion.  But the abatement NPV cost is only $110 trillion — a 6-to-1 savings or better.

Strangely, the authors never point this out directly. If you’re interested in why the IPCC underestimated adaptation costs, the study focuses on several areas:

  • Water: The UNFCCC estimate of US$11 billion excluded costs of adapting to floods and assumes no costs for transferring water within nations from areas of surplus to areas of deficit. The underestimate could be substantial, according to the new report.
  • Health: The UNFCCC estimate of US$5 billion excluded developed nations, and assessed only malaria, diarrhoea and malnutrition. This could cover only 30-50% of the global total disease burden, according to the new report.
  • Infrastructure: The UNFCCC estimate of US$8-130 billion assumed that low levels of investment in infrastructure will continue to characterise development in Africa and other relatively poor parts of the world. But the new report points out that such investment must increase in order to reduce poverty and thus avoid continuing high levels of vulnerability to climate change. It says the costs of adapting this upgraded infrastructure to climate change could be eight times more costly than the higher estimates predicted by the UNFCCC.
  • Coastal zones: The UNFCCC estimate of US$11 billion excluded increased storm intensity and used low IPCC predictions of sea level rise. Considering research on sea level rise published since the 2007 IPCC report, and including storms, the new report suggests costs could be about three times greater than predicted.
  • Ecosystems: The UNFCCC excluded from its estimates the costs of protecting ecosystems and the services they can provide for human society. The new report concludes that that this is an important source of under-estimation, which could cost over US$350 billion, including both protected and non-protected areas.

No surprise, really, given that the IPCC lowballs amplifying feedbacks and climate impacts, too.  In fact, even this study lowballs the  potential impacts of our current maladapter-driven climate policy, especially the very fat tail or the plausible worst-case scenario.

Anyway, if you’re interested in the important stuff — the enormous benefit of stabilizing at 450 ppm — just jump to Chapter 8, page 103, here.

The bottom line on adaptation:  I’m all for it.  That’s  precisely why I support a serious carbon price, since it is the only plausible way to 1) pay for domestic adaptation [and the share of developing country adaptation that we are ethically bound to provide] and 2) have a serious possibility of limiting future climate impacts to a level that one could actually adapt to.

This post is an update.

« »

37 Responses to Real Adaptation Is As Politically Tough As Mitigation, But Much More Expensive And Less Effective At Reducing Future Misery

  1. Jim Baird says:

    Real mitigation – Global Warming Mitigation Method – http://www3.telus.net/gwmitigationmethod/

    • Mark E says:

      See http://thinkprogress.org/climate/2012/06/29/506473/confirming-the-human-fingerprint-in-global-ocean-warming/#comment-385894

      The idea Jim sponsors – OTEC – is something in which he told RealClimate he has a financial stake. So take his advocacy with a grain of salt.

      To realize the benefits he talks about OTEC would have to be deployed on a huge scale. Repeat >>> huge scale.

      The idea expedites mixing of extra global warming BTUs from the ocean surface to the deep ocean. The assumption is that they will harmlessly disappear down there, leaving behind a gentler kinder climate system. In other words….

      OTEC relies on the same thinking that brought us tail pipe CO2 emissions: out of sight, out of mind. That did not work out so well did it?

      In short, OTEC is blind to a fundamental truth: the deep ocean is part of the climate system too!

      Of the various geoengineering options this one ranks right up near the top in terms of unanticipated nasty side effects.

  2. Amy Luers says:

    Unfortunately, there is no way around a major focus on adaptation, given that policies that we put in place today to reduce greenhouse gases are not going to significantly change extreme weather for decades. I would throw in another “adaptation framing” that is a “bait & switch” adaptation. That is when advocates talk about adaptation to get people to think about mitigation. It is a tricky line to walk, and one on which I would tread lightly.

    • Mulga Mumblebrain says:

      We must not forget the temporal dimension. As far as the Right, and 99% of denialists are of the Right, are concerned, ‘adaptation’ is for future generations, including their own children, to suffer. The denialists currently extant imagine that they will be safely returned to the carbon cycle by then, but it looks like they might be in for an unpleasant surprise.

      • I don’t think it is the majority position but I definitely agree this attitude is held by a non-trivial portion of the denialsphere right now. As nasty climate impacts start to pound the US I’ve noticed an appearance of comments like “just give me 30 more years.” Basically, “who cares if the theater is on fire as long as it doesn’t get to my row before the movie is over.”

        • Mulga Mumblebrain says:

          Another favourite line in the denialosphere is the ‘blame the teeming masses’ argument, which admits that there are real problems but blames it all on the ‘population explosion’ in the poor world. This has pretty obvious Malthusian implications, and, of course, the real culprit, the over-consumption of the greedy in the rich world, is never mentioned.

    • Robert Marston says:

      Adaptation will be needed for the changes we have set in motion already. The problem is that people are talking about adapting to continued fossil fuel emissions. And that, quite frankly, is an impossible proposition.

  3. Aleph Null says:

    Much of the adaptation talk entails two disturbing implications:

    (1) There will eventually be Solar Radiation Management (SRM, i.e. stratospheric sulfate aerosols) to restrain further warming – either that or Direct Air Capture (DAC) of carbon – which seems like a pipe-dream. The seawalls Bloomberg envisions would only buy a few decades in the absence of SRM or DAC.

    (2) There will be a massive culling of the human population which makes the black death look like a fire drill. Those who can afford to construct Biospheric bubbles will not have any excess funds to save anyone else.

    From an ecological or humanitarian perspective, it’s difficult to understand the difference between “rhetorical adaptation” and “real adaptation.”

    • Paul Klinkman says:

      When I talk about adaptation I talk about heat transfer devices drawing heat out of the Arctic Ocean and putting it into the 60 below zero Arctic air in winter. This restores the Arctic Ocean’s ice pack. I wouldn’t mind overdoing it by 20, to fight certain runaway aspects of climate change.

      When I talk about adaptation I talk about spraying fresh water mists into the air on wildly windy days on Arctic land, so as to coat the land with a thin layer of early snow or a late snow layer, so as to reflect sunlight back into the sky.

      I accept that other people have worse ideas and louder voices. Sometimes it’s not that the best ideas win, it’s only a shouting contest to see who gets the grant money. We’re the losers.

  4. Brian R Smith says:

    Joe, thank you for laying out this key economic argument so clearly. Common sense and the math together are powerful. I’m sure a lot of us are thinking it a good idea that you be invited to advise the administration while basic principles for climate strategy are still, we hope, being decided. Hope there’s a path for that. In any case, the economics of adaptation & mitigation -not even on the radar now in Washington- can’t be left on the back burner and instead can be the basis for political coalition building and getting the public’s attention. Inside moves in DC will decide policy, but important public support for sane policy will never kick in until the public actually gets the science.

    The president should address the nation on the urgency, and his views on action; but so should climate leaders. Media presence is fundamental.

  5. Planning to “adapt” to climate change without curtailing our CO2 output is like planning to adapt to another Chicxulub asteroid.

  6. dick smith says:

    Thanks for updating this post. I have shared the older post widely.

  7. Merrelyn Emery says:

    Triage won’t only apply to adaptation but will increasingly come into use in disaster relief as countries are hit by simultaneous multiple events which exhaust available resources. NGOs are already at their limits as Oxfam admitted during the Pakistani floods. Combine this with higher food costs and a faltering global economy. The only positive is the consequent reduction in emissions, ME

  8. Paul Klinkman says:

    Suffering for who?

    That’s why mitigation and adaptation don’t hold a candle to suffering. Suffering is a regressive tax, where the world’s poor pay with their lives, where the middle class go to impromptu Red Cross shelters and where the rich move to their other homes before the disaster hits.

  9. Tom says:

    Adaptation and mitigation are words that confuse your target audience (ie those that don’t understand the words…).

    I suggest replacing “mitigation” with “avoiding/reducing” and “adaptation” with “paying for the damage”.

    Really – one thing we have learned is words matter. This is too important to lose people on specialized jargon.

    In the real world adaptation could just as easily mean “adapt by using less CO2″ – and mitigation could mean “mitigate the damage by paying for it” – so it is a communications fail.

    • Mike Roddy says:

      I agree, Tom, “adaptation” in this context could lend itself to several interpretations.
      Tillerson’s speech where he says “we can adapt” is funny, but few people understand why.

      This needs to be clarified, and we may need a new word.

  10. Rabid Doomsayer says:

    What price humanity itself? Dollars mean nothing if we are not.

  11. Ozonator says:

    Is it just me or is everyone avoiding the elephant in the room aka eugenics~adaptation?

    Conserving eugenics and plantations, “ExxonMobil CEO Rex Tillerson … questioned the ability of climate models to predict the magnitude of the impact. He said that people would be able to adapt” (“Exxon’s CEO: Climate, energy fears overblown”; JONATHAN FAHEY, Associated Press; huffingtonpost.com, 6/27/12).

  12. Solar Jim says:

    Another great post by Joe Romm. Thanks.

    The only issue I have, besides the gargantuan money figures (in present value) which really indicate unsustainable damage to civilization, is the concept that we will be sustained if we do not head toward 350 ppm,equivalent starting now (or yesterday). This seems unlikely because 1) the biogeophysical response seems to be “non-linear” and 2) we are still early in the “Response Factor” from the past several decades of “emissions.”

  13. jaywfitz says:

    It seems to me as the issue of climate change is a moral issue at its core– rather than technical– where a society or individual feels entitled to sell out others or the future for immediate selfish gain. . .well, it’s that ethical attitude that must change first and that’s our primary adaptive task on which all else hinges.

    • Mulga Mumblebrain says:

      That precise attitude is the modus operandi of the parasite class, always has been and always will be.

  14. rollin says:

    People believed the earth was flat for a long, long time. People believed the earth was the center of universe for a long time also. In these cases, the beliefs did not change day to day living very much.
    Now we have climate change and resource depletion along with extreme population rise. All of these things actually effect people’s day to day lives and the general operation of society.
    Give the eventual obvious character of these current predicaments, it may only take 20 to 30 more years to convince most people of the truth versus 200 to 300 for the flat earth and earth centric mindsets of the past.

    • Merrelyn Emery says:

      Contextual and behavioural change can change beliefs and attitudes very quickly. Watching your house flood for the second time in months or your house explode in a firestorm while the neighbours whisper ‘global warming’ makes denial hard to maintain, ME

  15. Joan Savage says:

    Real world examples don’t have to be strictly mitigation or adaptation. Obama’s talking up energy-efficiency in structures. That would primarily mitigate demand for fossil fuel though it could, if well designed, also make structures better adapted to the new climate extremes of wet, dry, high winds, heat, and even some cold where it wasn’t before.

  16. I think that most Americans of a certain age remember the Fram Oil Filter commercial. “You can pay me now or pay me later.” Surely we can find a way to leverage that.

  17. prokaryotes says:

    Just found this study from 1999, thought i share it here

    Risk Perceptions, General Environmental Beliefs, and
    Willingness to Address Climate Change

    Our primary conclusion is that risk perceptions matter in predicting behavioral intentions. Risk perceptions are not a surrogate for general environmental beliefs, but have their own power to account for behavioral intentions. We think four secondary conclusions are worthy of mention. First, behavioral intentions regarding climate change are complex and intriguing. People are neither ‘‘nonbelievers’’ who will take no initiatives themselves and oppose all government efforts to reduce greenhouse gas emissions, nor ‘‘believers’’ who promise both to make personal efforts and to vote for every government proposal. Instead, most people are in the middle, favoring some actions and opposing others. It is an error to assume that most opponents to a particular proposal also oppose doing anything.

    Second, although risk perceptions and general environmental beliefs influence both voluntary actions and voting, there are significant differences among the demographic variables. Women are more likely to intend to take voluntary actions. For voting intentions, however, when the variables that measure climate change perceptions and environmental values are in the equation, it is better educated, older, men who are more willing to support government policies to impose public sacrifices in order to reduce greenhouse gas emissions. In summary, we find women disproportionately among supporters of voluntary actions, and the better educated disproportionately among supports of government policies.

    Third, knowledge about the causes of the global warming is a powerful predictor of behavioral intentions, independent from believing that climate change will happen and have bad consequences. Even though information immediately prior to the voluntary action questions identifies causes of climate change for respondents, willingness to act is predicted by knowing the causes before reading this information. We thought that perhaps being knowledgeable is a surrogate for salience, that people who think climate change is an important issue become informed. When we introduce salience measures into the equation (not shown), knowing the causes retains its explanatory power. So, we return to our initial hypothesis that prior knowledge (not solely from reading information just before answering questions) about what causes climate change fosters behavioral intentions to act on those causes. Finally, the success of the risk perception variables in accounting for behavioral intentions should encourage greater attention to risk perceptions as independent variables. The research on risk perceptions initially used psychometric scaling methods to illuminate perceptions of the riskiness of technologies and behaviors (Slovic, Fischhoff, & Lichtenstein, 1980; Slovic, 1987; 1992). More recent work has looked at risk perceptions of ecological systems (McDaniels, Axelrod, and Slovic, 1995; McDaniels et al., 1997).

    This work has taught us much about the way people conceptualize risks, but rarely looked at the consequences of these perceptions for behavioral intentions or actual behavior.

    As generally assumed, our results show that risk perceptions and knowledge increase people’s willingness to take steps that address environmental problems.

    Risk perceptions and knowledge, however, share the stage with general environmental beliefs and demographic characteristics. Although related, risk perceptions, knowledge, and general environmental beliefs are somewhat independent predictors of behavioral intentions. Our findings suggest some guidance for—as well as limits to what can be acomplished by—risk communication and information efforts. http://www.peccuv.mx/descargas/pdf/docuteca/Risk%20Perceptions,%20General%20Environmental%20Beliefs.pdf

  18. Paul Magnus says:

    It would be interesting to record and display the current state of suffering for the Katrina victims now and the latest Sandy and maybe even those for Irene.

    These unfortunate people are the first obvious americans to vividly experience the hand of GW.

    Of course there are a lot of other US incidents in the last 2yrs which are just as devastating but not so vivid – like the dustbowlification of Texas and the SW, with places starting to be abandoned. And the epic flooding that has recently occured and the tornados and derechos and the fires and the pinebeetle….(and even the BP oil spill maybe!)

    They will in time no doubt be repeatedly exposed to more and more extreme events as the frequency increase and most likely never will recover from the initial impacts.

    Adaption is fools gold in a 3C+ world.

  19. fj says:

    Most likely designs for the future will both mitigate and adapt to climate change in the most important ways.

    We have to back off immediately — just stop — destroying the environment that supports us while learning to live in the very hostile environment we have just created.

    And our best solutions will be characterized by profound integration with natural capital where human capital is the most important component; as we make our way into the future.

  20. BillD says:

    I think that most people will be surpised by the $1250 or so trillion estimate in climate change costs. My question is whether there is a time frame for this cost estimate(?) It seems clear to me that the climate changes that cause extinction for about 50% of the earth’s species will also seriously reduce the carrying capacity for humans, especially our ability to grow food.

    • fj says:

      Nature has a monopoly on the vast majority of services it provides to us and it is not terribly rational to give these services dollar values.

      Yes, the dollar costs to us can be projected but looking at the entire system . . . things will start to get quite chaotic and civilization must change dramatically to be more closely in tune with natural systems to better benefit from them; as well as the way we do wealth, economics, financials etc.

      We must proceed forward with life and death urgency with those variations of life or death skits better left to comedy routines.

      • Raul M. says:

        I guess that only being intuitively in tune with nature could leave us to be less mentally able to see the prospects of order. For as the nature becomes chaotic then the in tune person could also become chaotic. Certainly understanding of causes of chaos is a better way to stay in tune.

    • John McCormick says:

      Bill, thanks. Someone finally mentioned food. The comments, thus far, have been about semantics and framing.

      My great fear is that the rain-fed agriculture in the Midwest North America will continue to unravel as precip timing and intensity are influenced by the melting Arctic ice.

      It will take federal government involvement in an effort to assure farmers have surface water irrigation as backup while the farmers radically change their crop choices and methods. Call that adaptation, if you will, but adequate grain supplies are what will keep the world population from flying apart.

      • Mark E says:

        It is remarkable how much social media noise there was over Hurricane Sandy and how relatively little there has been about what was – prior to Hurricane Sandy – the biggest (and continuing) natural disaster of the last few years

        • Merrelyn Emery says:

          Yes, the majority of social media responses so far appear to be in the service of the maladaption of superficiality of which neophilia and what is called here ‘the wow factor’ are prime components, ME

      • Joan Savage says:

        I’d mentioned energy-efficient structures, but I take your point about food.
        A merge between the concept of mitigation and concept of adaptation is low-till, low-fertilizer, no-irrigation farming with heat-tolerant cultivars. Less fossil fuel is used, food still grows.

        • John McCormick says:

          Joan, I was thinking about prolonged drought in America’s rain-fed grain basket. Even heat tolerant cultivars need water.

  21. Great article, thanks.

    On framing, I’ve noticed many people I talk to about climate change in everyday life have really taken to the “steroids” metaphor.

    This metaphor gives them an easy way to absorb the facts about the various kinds of “steroids” we are adding to the weather. I call it a “steroid cocktail”:

    * more heat energy in the air
    * more heat energy in the oceans
    * more water vapor fuel for storms

    It is the reality of more energy/fuel in our weather system seems to be the “aha” moment for many. So I always talk about the “steroids” using the terms “energy” or “fuel”.

    The water vapor “steroid” is not usually as discussed as others. Trenberth says water vapor increases around 7% per degree C. So when talking about 6C warming we can also talk about a 40% increase in water vapor fueling storms, deluges and flooding. We have already seen what 5% increase can do to extreme rainfall events.