Advancing the Planetary Boundaries Hypothesis

For decades, environmentalists and many earth scientists have been warning that humans are exceeding the earth’s carrying capacity, that our numbers (7 billion and counting) and the way we farm, fish, and live is overwhelming the ecosystems we depend on.

In 2009, Johan Rockström and two dozen colleagues proposed

a new approach to global sustainability in which we define planetary boundaries within which we expect that humanity can operate safely. Transgressing one or more planetary boundaries may be deleterious or even catastrophic due to the risk of crossing thresholds that will trigger non-linear, abrupt environmental change within continental- to planetary-scale systems.

When the planetary boundaries concept was published in Nature, it was immediately recognized as controversial. “The new paper has already drawn strong reactions from other scientists, some glowing, some harsh,” wrote Carl Zimmer in Yale Environment 360.

An accompanying editorial in Nature described the paper as “a creditable attempt to quantify the limitations of our existence on Earth,” but also noted:

For the most part, the exact values chosen as boundaries by Rockström and his colleagues are arbitrary. So too, in some cases, are the indicators of [environmental] change…Furthermore, boundaries don’t always apply globally, even for processes that regulate the entire planet. Local circumstances can ultimately determine how soon water shortages or biodiversity loss reach a critical threshold.

Nature made sure to include commentaries from scientists not involved with the paper, whose expertise enabled them to address specific aspects of the planetary boundaries proposal. The respondents had their own quibbles, but overall they found the framework useful.

Since 2009, the major themes laid out in the planetary boundaries proposal have been the subject of high-profile symposiums and institutional reports on the state of the earth. See, for example, the recent Planet under Pressure conference, which declared that “the continued functioning of the Earth at risk.” In April, the UK’s Royal Society released it’s much discussed report that said humanity would continue “to drift into a downward spiral of economic and environmental ills,” unless global population and consumption rates were curtailed.

In case you weren’t getting the picture, last week Nature published another big paper on global ecological trends that warned of a “planetary-scale tipping point,” due to, as the University of California press release said, “population growth, widespread destruction of natural ecosystems, and climate change.”

Those of you not yet in a fetal position, whimpering “please, no more,” might want to sing along to this classic.

Or, if you’re a glass half full kind of person, you may want to check out some fresh new critiques of the planetary boundaries concept. There is a slew of them that, taken together, offer a counter-narrative to the one that I just chronicled. Let’s start with Erle Ellis, a geographer at the University of Maryland, and his essay in the fall issue of the Breakthrough Journal:

The “planetary boundaries” hypothesis asserts that biophysical limits are the ultimate constraints on the human enterprise. Yet the evidence shows clearly that the human enterprise has continued to expand beyond natural limits for millennia. Indeed, the history of human civilization might be characterized as a history of transgressing natural limits and thriving. While the Holocene’s relatively stable conditions certainly helped support the rise and expansion of agricultural systems, we should not assume that agriculture can only thrive under those particular conditions. Indeed, agriculture already thrives across climatic extremes whose variance goes far beyond anything likely to result from human-caused climate change.

Ellis is also a contributing author of an essay in the June issue of Bioscience which aims to stake out a middle ground between two poles: The Limits to Growth mentality (which clearly underlies much of the gloomy aforementioned assessments) and the don’t worry, human ingenuity will come to the rescue mindset. The former attitude can’t feasibly address the needs of the developing world and the latter attitude ignores the legitimate and mounting ecological stresses on the planet.  Ellis and his fellow Bioscience authors write:

We assert that an emphasis on global biophysical limits at the expense of a focus on realistic solutions is insufficient, as are assumptions that technologies can always solve environmental problems.

Instead, they suggest that for scientists to be truly relevant,

a vision of planetary opportunities needs to become a focal point for global change research, with sophisticated exploration of the synergies and tradeoffs between human and biophysical systems that will ultimately determine the success of our species and our planet’s ecological heritage.

This notion of tradeoffs is at the heart of a new report just released by the Breakthrough Institute (TBI), which argues that the planetary boundaries framework “has serious scientific flaws and is a misleading guide to global environmental management.”

Their conclusion is based on an “extensive literature review” of the science underlying the 2009 Nature paper. It’s worth pointing out that neither TBI’s report or the Nature paper were peer reviewed.

A judgement of TBI’s assessment is beyond the scope of this post. I’d have to invest many, many hours cross-checking studies and following up with researchers. I’m hoping that some of my colleagues staffed at news outlets will take the time to drill down into TBI’s claims. What I can say is that I’ve read their report, reread the Nature paper it is critical of, as well as other related publications.

I’ve also reached out to Jon Foley, a University of Minnesota earth scientist, who was a contributing author of the 2009 Nature paper. Foley, on Twitter, and in an email exchange, has been dismissive of the TBI report. He says it is “poorly thought out, and doesn’t say anything especially useful or new.” He also asserts that the TBI report “mischaracterized the original PB [planetary boundary] study, and ignored what many other people (including us) had said before.”  Here, Foley is referring to previous critiques made of the planetary boundary framework in that collection of Nature commentaries I mentioned earlier, as well as the hedging and qualifications made in the original Nature paper, which did candidly admit: “The knowledge gaps [in assessing biophysical limits] are disturbing.” (Just as an aside, Foley and his Nature co-authors have been similarly accused of not paying sufficient tribute.)

At this point, the average reader can get lost in the weeds, trying to sort through the various claims and counter-claims. But what I have noted about Foley’s rebuttal is that, while sweeping, it doesn’t specifically address the case that TBI has mounted against the scientific foundation for the planetary boundaries, or some of the flawed assumptions that TBI asserts the concept is is based on.

Based on my reading of the report and exchanges I had with its lead author (and TBI Research Associate), Linus Blomqvist, I’m seeing issues raised that are worthy of debate. Here is Blomqvist, in an email to me, explaining what he sees as the bigger picture:

Environmental management tools and concepts must be adapted to the practical reality of the environmental problems it addresses. By trying to fit too many environmental variables in the same framework of boundaries and tipping points, PB  [planetary boundaries] lost connection to actual on-the-ground challenges. For example, a single boundary cannot capture the fact that in some regions, increased nitrogen use, freshwater use, and perhaps even land-use change could benefit people, whereas in other regions the opposite is true. So for nitrogen the real challenge is to apply an adequate level to each field: enough to provide high yields, but not excessive in a way that causes negative side-effects.

Both positive and negative impacts of environmental change on human welfare must be recognized. The truth is that increased nitrogen use, freshwater use, land-use change, and other human impacts on the environment have historically brought huge benefits for human material welfare. Policies that ignore these positive benefits and only see environmental change as negative are misleading. Linkages between environmental change and human welfare in policy frameworks like planetary boundaries are all too often just implicit assumptions that are based on aesthetic preferences for non-human nature rather than any empirical ground. This, I would say, is the most pressing weakness in most of environmental science today – it really is time to build a transparent, scientifically sound, and empirically grounded body of knowledge on the linkages between environmental change and human material welfare, in which aesthetic and material aspects are distinguished as clearly as possible.

Foley, being a self-described pragmatist, would be an ideal person to engage these points. In doing so, he could help design a revamped planetary boundaries framework, one that reconciles value judgements and real world tradeoffs with science.


14 Responses to “Advancing the Planetary Boundaries Hypothesis”

  1. BBD says:

    Interesting that both Foley and Stuart Brand describe themselves as pragmatists. Brand uses the term ‘ecopragmatist’ and may have even coined it (?). There’s hope yet.

    This is a very interesting debate indeed. On the face of it, the obvious reaction is as expressed above: the PB approach provides a very useful framework within which to consider human impacts on the planet, but it’s a work in progress.

  2. Andy says:

    Seems like and area that’s probably worth further study but, like many things, predictions on tipping point will be fraught with significant uncertainty and imprecision.

  3. Nullius in Verba says:

    Does advancing technology ever pass a tipping point for the ease of adaptation?

  4. huxley says:

    We’ve been hearing about tipping points and planetary boundaries since the Seventies.

    I still have a copy of “Limits to Growth” (1972), which forecast that by now we would be almost out of aluminum, copper, gold, lead and mercury. According to the LtG standard model, nonrenewable resources would collapse early in the 21st century, while food per capita and industrial output would peak around 2015, followed by a terrible and inexorable decline. A generation later, human population would collapse.

    Not exactly what has happened.

  5. MarkB says:

    I read somewhere that every Biblically-based end-of-the-world prediction made over a couple hundred years just happened to work out to by in the contemporary ‘near future.’ Those scholars and itinerant preachers who made such predictions are figures of fun now. After all – how many times can you be wrong before you just stop trying? Somehow, the neo-malthusians just have no shame. Or rather, they put those poor fundamentalist Christian knuckleheads to shame with their willingness to brazen it out. When do you just tell such people “No – this time is not different?” What they are doing has nothing to do with science. They will accept no amount of falsification.

  6. Marlowe Johnson says:

    Keith do you get paid by BTI or is just an adulation thing for you?

  7. Keith Kloor says:

    #6 I would love it if someone actually paid me to blog here. I take it you didn’t like their report? Or my write-up of it? Or should I follow Eli’s directive and only blog about think tanks that have an official seal of approval from Climate Progress?

  8. Tom C says:

    Huxley and MarkB – BBD has decreed that Ehrlich and “Limits to Growth” are not acceptable topics.

  9. BBD says:

    Sigh. No, I said that using Ehrlich as a proxy for all predictive environmental science was a false equivalence. Now you know what to look out for, you will see contrarians doing it all the time. And you will see it for the crude distractive trick that it is.

    >> Marlowe

    Eh, come on, be fair. The BTI sounds a bit confrontational, but Rockstrom et al. was (though caveated throughout), *positing* PBs. As I said @ # 1, the proper attitude to this should be a work in progress. Undertaken by pragmatists with contrasting (though perhaps not ultimately irreconcilable) viewpoints.

    I though Keith’s write-up of this (and previous post) were extremely even-handed. And goodness knows how long they took to prepare. As someone with a 26-hour day, I feel a certain empathy for Keith. Who does not get paid for this.

    Rant over; back to the fun & games.

  10. Jonas N says:

    Dr Johan Rockström is a swedísh agronomist, who has made a career out of assessing alarmism from all kinds of fields and sources, and presenting them together as ‘Everyting is bad or even worse, and together it is even worser, much worser …’

    He is not a scientist (although he sometimes has used the title ‘Professor’). Rather he is a skillful rent seeking government- and bureaucracy support thrawling entrepreneur. He is a member of the Swedsih Gov:s ‘future commission’.

    I have seen and listened to him a few times, and he is essentially a professional alarmis aktivist. Whatever he presents is that it always is the ‘worst of the worst, and since there are both uncertainties, non-linearities, and unknown tipping points, it could still be much worse’. 

    You can see him in this TED-talk here

    It’s impossible to take him and his quantitive ‘assessments’ seriously if you are the least bit scientifically inclined. But the politicians like him and feed him and his politically erected institute millions. And he is of course buddy with many of the other political enviro-warriors.  

  11. Steven Sullivan says:

    I too see the love affair with TBI is still going strong among certain bloggers trained to seek the journalistic he said/she said. Given the rebuttals Nature itself published, we should care about TBI’s  take exactly why?

  12. Tom Scharf says:

    Science academia producing hugely misleading scare mongering press releases is SHAMEFUL:

    “we’re on a much worse collision course with Mother Nature than currently thought”

    “planet’s ecosystems are careering towards an imminent, irreversible collapse”

    “authors predict could be reached this century, the planet’s ecosystems, as we know them, could irreversibly collapse in the proverbial blink of an eye”

    “The odds are very high that the next global state change will be extremely disruptive to our civilizations”

    “we won’t be able to delay, never mind avert, a planetary collapse”

    This is how they make their living?  I am amazed at how much energy is piled into this type of effort that could be spent toward something much more useful.  Cancer research?

    This type of “research” is going to be target number one when science research budgets get whacked.  Does anyone seriously believe that if we funded planetary tipping points / boundaries at 10% of its current rate that anything would change down the road?

    At some point these eco rent seekers need to really justify their existence.  The freeloading phase needs to end.   

  13. huxley says:

    Tom Scharf @ 12: Tipping points are the new, improved version of the ongoing environmental scare, now that global warming and climate change have lost their pizzazz and are in danger of falsification.

    This appears to be a calculated marketing campaign in coordination with Nature magazine article, the IPCC (whose latest publication is MANAGING THE RISKS OF EXTREME EVENTS AND DISASTERS TO ADVANCE CLIMATE CHANGE ADAPTATION), and the current Rio+20 summit conference.

    I don’t mean to dismiss the threat of tipping points, which have occurred in the past even without humans, but the environmental scientists have been scaring the daylights out of everyone since the 1960s. Some tipping point disaster could happen tomorrow or might not for the rest of the century. What do we do with this information?

  14. Jim South London says:

    Planet Tattoine in Starwars about the same size as Planet Earth.Looks bloody big from up there..

    So dont you think you over estimate the impact of Mankind and the vast ness of the Earth.

    In Star trek planet Earth manged to support 9 Billion all Borg so why cant it support 9 Billion all humans.

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