earthDr. Michael Mann is a professor of Meteorology at Penn State University and the director of the Penn State Earth System Science Center. He holds joint appointments in the university’s Department of Geosciences and the Earth and Environmental Systems Institute.  

Dr. Mann is currently involved in a number of projects studying climate change impacts, such as the influence global warming may have on malaria outbreaks. He is also investigating natural climate variability in an effort to better quantify the effects of human-caused climate change. Several of his current projects are being funded by the National Science Foundation, the National Oceanographic and Atmospheric Administration and the Pennsylvania Department of Energy.

Dr. Mann holds a B.S. in Physics and Applied Math from UC Berkeley, an M.S. in Physics and a Ph.D. in Geology and Geophysics from Yale University. He has received numerous awards and authored hundreds of publications, including his most recent book, The Hockey Stick and the Climate Wars: Dispatches from the Front Lines.

Planet Experts: You have long been on the frontline of the climate change debate. What specific type of research are you engaged in at the moment?

hockeystickDr. Michael Mann: Interestingly enough, what most people know me for is my paleoclimate work – reconstructing past climates from so-called ‘proxy climate’ data, like tree rings, corals, ice cores – what led to the so-called “hockey stick curve” a decade and a half ago. And I do continue to do some research related to paleoclimate, but actually a lot of work that I’m doing now is more to do with future climate change projections, understanding them, estimating impacts that those climate changes might have, understanding how climate change might affect river flows in the mid-Atlantic states here in Pennsylvania – because the Department of Energy is very interested in that.

PE: In 2001, you co-authored the third assessment report for the Intergovernmental Panel on Climate Change (IPCC), specifically on the chapter of observed climate variability. The most recent edition of the IPCC report warns that the climate is warming much faster than predicted. Does that match up with your own research?

MM: If you just look at global average temperature, it turns out that historically the projections have been reasonably accurate. The current warming is within the envelope of what the climate models have predicted in the past, but herein lies the rub: When you look at some of the specific features of the climate model projections, there are indeed certain responses that appear to be larger and taking place faster than the models predicted just a few years ago.

One example is arctic sea ice. Sea ice is disappearing in the arctic faster than the climate models predicted. There’s a new study out that shows that the Greenland ice sheet and the West Antarctic ice sheet – the two major ice sheets – are losing ice, once again faster than we expected them to. And that means that they are contributing to sea level rise faster than we expected them to. Because of that, we do expect sea level rise to be larger than many of the climate models predicted less than a decade ago.

So there are definitely a number of features where the climate is changing faster and the magnitude of change is larger than the models predicted. I often like to bring that up in the context of discussions about uncertainty. You often hear the climate change critics say, ‘Well, since there’s uncertainty in the science we shouldn’t act.’ Which is frankly absurd, because uncertainty can play out in both directions. And it turns out in many respects uncertainty is playing out in such a way that the changes are worse than what we had predicted just years ago.

PE: For some politicians, accepting climate change is tantamount to career suicide. Do you think there are any climate deniers who, behind closed doors, might admit that they are on the wrong side of history?

MM: Unfortunately, at the base of this is the fact that a number of very well-heeled private interests – the Koch brothers in particular – have spent tens if not hundreds of millions of dollars poisoning – literally poisoning – our public discourse over climate change by funding professional climate change deniers, creating front groups and funding think tanks that exist to cast doubt on the science of climate change. Funded by the Koch brothers, or in many cases funded by their fossil fuel interests.

One of the other things that they’ve done is to challenge Republicans that come out and express a thoughtful view about climate change. Any Republican now who comes out and says they accept what the scientists have to say will almost certainly be targeted in the primary campaign – it’s what’s known as being “primaried” out of their seat. One of the best examples of that is Bob Inglis, a Republican from South Carolina, who was primaried out of his congressional seat some years ago by a candidate heavily funded by the Koch brothers.

And the problem is that these special interests have made climate change denial a litmus test for one of the two major parties – the Republican party. And there are many Republicans – and I think there’s evidence to support this – who off-camera, confidentially, will tell you, ‘We accept the science, we know this is a real problem, we know that there are some risks associated with climate change.’ They might say that the risks are less than what others are saying, but they basically accept the science.

What they’ll tell you is, ‘Look, if I say so publicly, I’m going to be primaried out of my position by the Koch brothers.’ And there’s no way around it. That is the fundamental problem here.

That is why there is such a disconnect between what the scientists have to say and what the public thinks. The recognition that the globe is warming, that humans are influencing our climate – depending on the poll that you look at, it’s somewhere in the range of 65-70 percent or so. And if you look at the scientific literature, you’ll find that over 97 percent of scientists who study this concur with the basic consensus that climate change is real, it’s caused by us, and it represents a threat if we don’t do anything about it.

And the only reason that gulf exists is because tens if not hundreds of millions of dollars of the Koch brothers and other fossil fuel interests are poisoning the well with what is arguably the most massive, well-funded and well-organized disinformation campaign in the history of civilization.

PE: The primary criticism advanced by Republicans against investments into renewable energy projects and implementing carbon taxes is that such approaches negatively impact an already weak economy and cost thousands of jobs. What is your response to this argument?

MM: It’s wrong. The premiere firm that does economic modeling for policymakers, Regional Economic Models, Inc. (REMI) – full disclosure, the president of REMI was a school friend of mine at the University of Massachusetts – has now done a number of studies for various states to look at what the impact of a modest carbon tax would be on the economy. And what they find is that any deficiencies that come from meeting these standards can actually lead to economic growth.

So the argument is wrong, but even if it weren’t, you can talk to any economist who studies the cost-benefit of climate change mitigation and they will tell you the costs of inaction are far greater than any cost to taking action now. And right now it would be fairly cheap. It will be far more expensive if we delay action for another decade. We’ve already allowed quite a bit more climate change damage to occur.

Leading economists, people like Bill Nordhaus at Yale or Marty Weitzman at Harvard or Gary Yohe at Wesleyan – the three individuals one might consider the leading academics who study economic cost-benefit analysis of climate change mitigation – they will tell you that inaction is the most expensive scenario. The effects it will have on food, on water, on national security, on public health, the cost of inaction is far greater.

PE: In your articles and books, specifically The Hockey Stick and Climate Wars: Dispatches from the Front Lines, you have discussed being the target of right wing attacks and even death threats. Can you explain how that began?

MM: It really was with the publication of the hockey stick graph back in the late 1990s. That graph became an almost iconic image in the climate change debate because it told a very simple story, very visually demonstrating the reality of global warming, that there’s something unprecedented taking place in our climate today that, by inference, very likely has to do with human activity.

And because it was such a potent image that conveyed the reality of climate change to the public, those same vested interests that I talked about before – fossil fuel interests, the Koch brothers, those who will do anything to prevent action being taken to reduce carbon emissions – saw the need to discredit that graph. They engaged in very personal attacks aimed at discrediting me as a vehicle for discrediting the graph itself. So as I describe in the book, since the hockey stick graph was featured prominently in the summary for policymakers in the 2001 IPCC assessment, it became a target of attack by climate change deniers. By a professional, well-funded climate change denial machine. It was focused on me and discrediting my work.

And I decided to fight back. I decided not only did I need to fight back to defend my integrity, my reputation, but I owed it to the rest of the scientific community, especially younger scientists. I couldn’t allow these villains to be successful in their effort to attack and discredit me because that would send a message to other scientists that if they too choose to speak out on the implications and threat of climate change, that they would be subject to a similar, concerted attack that would discredit them as scientists. I couldn’t allow my detractors to be successful because it would send such a dangerous message to the rest of the scientific community. So I ultimately decided to embrace this role as a public figure in the climate change debate and use it to try to inform the discussion and raise public awareness.

It’s not what I set out to do. I double-majored in applied math and physics at UC Berkeley. I didn’t have in mind a future political career. I didn’t realize that those choices would eventually put me in the center of this raging debate. But once I found myself there, involuntarily, I decided that the most responsible thing to do was embrace that and use it to do good.

And there have been dark moments. I’ve been subjected to vicious hate mails and nasty phone calls, the FBI had to investigate an envelope containing a white substance sent to me that resembled anthrax. I’ve had my life threatened, I’ve had the life and safety of my family threatened. All because I’ve chosen to fight back, to defend the science, to inform the discussion, to call out disinformation where I see it – which perhaps makes me even more of a target.

And people sometimes ask me, if you could do it all over again, would you make a different choice? If I could go back to that point where I decided to leave theoretical physics and switch into climate science because I thought there were some really fascinating unsolved problems that I could use my math and physics background to really do some interesting work in that field. People ask me, if I could go back, would I stay in theoretical physics and avoid all of this stuff? And the answer is I wouldn’t.

Though I’ve experienced some dark moments and suffered trials and tribulations for the role I’ve taken in the climate change debate, it’s hard for me to think of something more noble that I could do with my life than try to inform this very important discussion about what may be the greatest societal challenge we’ve ever faced.

PE: In your opinion, what is our time frame with respect to fighting climate change before a catastrophically changed planet is inevitable?

MM: The actual situation is a little more nuanced than that, in the sense that it’s less like a cliff that we walk off and more like a steeply descending slope. And we may miss the 450 ppm CO2 offramp on that highway. It doesn’t mean we give up. We still try to get off at the 460 ppm offramp, and if we miss that then we take the next one. With each of those junctures, however, there is a greater probability that we commit to some irreversible changes.

A  good example is the ice sheets, the west antarctic ice sheet and the Greenland ice sheet, which have great potential to raise sea level. There have been a series of studies just over the past few months that suggest we may now have passed the point of no return. We may now have committed to enough melting of the west Antarctic ice sheet to give us an additional 10 feet of sea level rise, no matter what we do. We can’t stop it now. The warming ocean is melting the ice sheet from below, it’s destabilizing it and there’s nothing to hold it back now. Now that could take centuries to happen, but we don’t know. It could happen faster than that.

So that’s one example. That tipping point we may have already crossed. But the tipping point of melting the Greenland ice sheet, we may not have passed that. And the tipping point of committing to the 2 degree celsius warming of the planet relative to pre-industrial time, we may soon commit to that. I actually wrote an article in Scientific American about that very question: Can we still avoid breaching that particular limit? And we probably can, but to do that would require concerted action immediately.

We really need to start ramping down our carbon emissions immediately, and by several percent per year, which is a tall order and would require concerted policy action at a time – at least in the U.S. – when there doesn’t seem to be nearly enough political will.

So there isn’t a physical obstacle to keeping warming under 2 degrees C. Right now there simply appears to be a political obstacle, and that’s reason for optimism. Because political obstacles can be overcome, physical obstacles cannot. You can’t change the laws of physics but hopefully you can change people’s hearts and minds.

9 Responses

  1. hikesocal says:

    This was like reading an interview with Bob Dylan talking about how he writes songs.


    But while I wholeheartedly agree with Mr. Mann's pointed reference to the power of the Koch brothers it doesn't explain away that CITIZENS are still the ones responsible for this faux debate over climate change. I don't care how much money was spent on commercials telling me the sky was green because I'm not going to be swayed in knowing it's blue. So the question becomes "Why do people willingly fight against what's in their own best interest?"

    Until the "deniers' have a tangible financial benefit from actions taken to address climate change, belief will continue to win out over fact. We can never, ever forget that America isn't a particularly bright country and the concept of having an "enemy" has been driven down people's throats for so long that a Pavlovian response to forward-thinking exists.

    Money. It's all about money. Not money 100 years from now. Money today. And we're not that far away.

    Again, great job with this. Planet Experts continues to deliver the goods.

    • Ron says:

      "Why do people willingly fight against what's in their own best interest?"
      Because carbon taxes, skyrocketing energy prices and everything that follows is hurting the folks pocket, especially the ones that can least afford it here in the US. Solar and wind don't cut it. In Germany, guess what they are importing (which waste fuel) to supplement the power grid when the sun does not shine or wind is not sufficient ? TREES cut from forest in the south eastern part of the country. I'm tired of seeing thousands of acres of my southern US homeland being raped of its trees, when clean coal, or better yet natural gas is plentiful. Not to mention the wildlife that is killed or displaced in the process. Evidence debunking AGW is widespread and growing every day. All the doomsday predictions from just 5 or 10 years ago is working against you, and quite embarrassing for you. Would you like a list of all the "peer reviewed" papers on AGW that busted? Would you like a list of all the big money donations that are lining the pockets of the AGW scammers? Much of which comes from the taxpayers. Sea level rise is slowing, glaciers in the Scottish highlands are growing again, sea ice is setting records in Antarctica, as well as on the mainland, ice in the arctic up over 60% from 2 years ago and Greenland gained 200 billion tons of ice in the ice year completed 2 days ago, and temperatures are falling in the US. Severe weather is decreasing in numbers and severity, along with less drought and forest fires in the last 10 years. When the AMO flips in a few years the oceans will cool again as they have always done. It cyclical. To deny these facts is irresponsible on your part. No one wants a polluted world and maybe we should focus on real pollution problems in china, and not focus on C02 which is NOT pollution and IS greening our planet. I have a good idea, why don't YOU pay the carbon tax for me and leave me and my family alone. Stay out of my pocket !

  2. Gnomish says:

    Was that Mr. Mann on the corner with the sandwich board that said 'The End of the World is Nigh'?
    Well, wake me when oblivion is over, OK? It's hard to whip a fervor to a froth every day!
    Being the Honey Boo Boo of the Climageddon Trailer Park was doomed. Conspiracy ideation and recursive stupidity are diagnostic. What we have here is a case study of psychosis.
    By the way- if there were some global warming, it would be OK. Don't tax my breath over it, hmm?

  3. Banquo's Son says:

    Mann would have us believe that if we let Banks trade in CO2, they'll save the world.
    They'll save the planet, your kids/grandkids, the Arctic, the Polar Bears, the ocean, the glaciers and Nth/Sth Pole, save the taste of your coffee and beer, the Banks will also save our oysters. On and on. ALL if we let Bankers trade in carbon.

    Man is right about one thing, there are some villainous greedy selfish people out there clamouring for tax payer dollars.
    And it isn't who he says it is.
    I look forward to Mann's upcoming court cases.

  4. Bob Armstrong says:

    If he "double-majored in applied math and physics" he should damn well be able to do the basic calculations of radiative balance which show James Hansen's clam that Venus is an example of a "runaway greenhouse" is a quantitative howler by an order of magnitude and repudiate it .

    But it's hard not to see him as a simple liar when he makes claims that he and his watermelon friends are losing the debate because of a few 10s of millions when their side spends that just on flying around to multiple annual conferences ( parties ) at exotic resorts around the globe .

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