Tag Archives: Steve Carpenter

Interesting recent resilience papers

A few recent papers on resilience are quite exciting.  Below are brief pointers to them.  Hopefully we will have more time to right about them in the future.

  1. Steve Carpenter and colleagues Early Warnings of Regime Shifts: A Whole-Ecosystem Experiment in Science (DOI:10.1126/science.1203672)
    Uses experimental lakes to show that early warning signs of regime shifts can be detected (with high frequency monitoring).
  2. Kendra McSweeney and Oliver Coomes Climate-related disaster opens a window of opportunity for rural poor in northeastern Honduras PNAS 108(13) 5203-5208 (DOI: 10.1073/pnas.1014123108)
    Response of a community in Honduras to Hurricane Mitch shows that disasters can provide opportunities for the poor.
  3. JP Evans Resilience, ecology and adaptation in the experimental city. Transactions of Institute of British Geographers 36 (2): 223-237 (DOI: 10.1111/j.1475-5661.2010.00420.x)
    A geographer reflects on the consequences of resilience approaches to cities – especially Urban LTER in USA.
  4. Bill Currie Units of nature or processes across scales? The ecosystem concept at age 75.  New Phytologist 109(1) 21-34. (DOI: 10.1111/j.1469-8137.2011.03646.x)
    An ecosystem ecologist looks at the history, problems, and possible future of the ecosystem concept.

Resilience and Regime Shift videos

Kit Hill a Masters student at the Stockholm Resilience Centre made the three short videos below to introduce the concept of resilience and the idea of a regime shift.

Resilience from Kit Hill on Vimeo.

Beating Down Resilience from Kit Hill on Vimeo.

Regime Shift from Kit Hill on Vimeo.

This video was made in order to help people understand the concept of a Social Ecological Regime Shift.

Kit’s efforts are part of a larger project to create a set of communication and teaching resources that can be used to communicate different aspects of resilience thinking.

For more information on resilience see:
the resilience alliance,
Stockholm Resilience Centre, Brian Walker and David Salt’s book Resilience Thinking, or collection of resilience papers on Mendeley.

Expansion of social-ecological systems science

The concept of social-ecological systems has been gaining increased interested in science. Below is a graph showing papers whose topic includes social-ecological systems. During the 1990s there were a few publications and then a rapid rise during the 2000s.  Two influential books articulated social-ecological ideas:

Papers from ISI - social-ecological or social ecological and Systems

The top five journals are dominated by Ecology and Society:

  1. Ecology and Society (78)
  2. Global Environmental Change (13)
  3. Ecosystems (13)
  4. Proc. of National Academy of Science (USA) (10)
  5. Ecological Economics (8)

The most prolific authors are a group of people who are working to bridge the social and natural (with number of papers in brackets).  The top two authors, Carl and Fikret, were editors of the Linking and Navigating books.

  1. Carl Folke (26)
  2. Fikret Berkes (14)
  3. Steve Carpenter (14)
  4. Per Olsson (13)
  5. J. Marty Anderies (11)

The universities with the most publications are:

  1. Stockholm University (41) (where Carl Folke is located)
  2. Arizona State University (27) (where Marty Anderies and a number of SES researchers are)
  3. University of Wisconsin (19) (Steve Carpenter)
  4. University of Manitoba (18) (Fikret Berkes)
  5. Indiana University (14) (Elinor Ostrom and formerly Marco Janssen, both of whom have frequently published on social-ecological systems)

A history of Stommel diagrams

Tiffany Vance and Ronald Doel have traced the history of the Stommel diagram from physical oceanography into biology, in their 2010 paper Graphical Methods and Cold War Scientific Practice: The Stommel Diagram’s Intriguing Journey from the Physical to the Biological Environmental Sciences in Historical Studies in the Natural Sciences (DOI: 10.1525/hsns.2010.40.1.1.)

The paper provides an rich history of how the innovative oceanographer Henry Stommel created his diagrams to emphasize the cross-scale dynamics of the ocean (See figure below), and how his diagram was adapted by biological oceanographers. However, they miss how Stommel diagrrams moved into ecosystem ecology and sustainability science.

Below I present a series of Stommel diagrams.  The first three figures are reproduced in Vance and Doel’s paper, the later three are from sustainability science.

First, Stommel’s original figure, which was designed to show how oceanic processes varied across scales, and that sampling efforts had to be planned with a consideration of these.

Schematic diagram of the spectral distribution of sea level (From Stommel 1963. Varieties of Oceanographic Experience. Science)

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Responses to Early Warning Signals for Critical Transitions paper

The recent paper by Marten Scheffer and other resilience researchers paper Early Warning Signals for Critical Transitions (doi:10.1038/nature08227) has been reported in a number of places including Time, USA Today, and Wired.  While many newspapers just reprint the press release, several articles add something.

A USA Today article Predicting tipping points before they occur quotes Brian Walker:

“This is a very important paper,” says Brian Walker, a fellow at the Stockholm Resilience Center at the University of Stockholm in Sweden.

“The big question they’re trying to answer is, how the hell do you know when it’s coming? Is there any way you can get an inkling of a looming threshold, something that might be a warning signal that you’re getting to one of the crucial transition points?”

Wired magazine article Scientists Seek Warning Signs for Catastrophic Tipping Points quotes several sceptical scientists:

“It’d be very nice if it were true that there were precursors for tipping points in all these diverse systems. It’d be even nicer if we could find these precursors. I want to believe it, but I’m not sure I do,” said Steven Strogatz, a Cornell University biomathematician who was not involved in the paper.

The difficulty of early detection is especially pronounced with markets. Computer models can replicate their bubble-and-crash behavior, but real markets — buffeted by political and social trends, and inevitably responding to the very act of prediction — are much cloudier.

“It is hard to find clear evidence of bifurcations and transitions, let alone find an early warning system to detect an upcoming crash,” said Cars Homme, an economic theorist at the University of Amsterdam.

The most promising evidence of useful early warning signs comes from grasslands, coral reefs and lakes. Vegetation-pattern-based early warning signs have been documented in several regions, and transition theory is already being used to guide land use in parts of Australia.

The U.S. Geological Survey is currently hunting through satellite imagery for signals of impending desertification at two sites in the Southwest. They’ve studied desertification there by painstakingly measuring local conditions and experimentally setting fires, removing grasses and controlling the fall of water. But so far, the vegetation patterns that indicated tipping points in the Kalahari haven’t shown up here, though this may be due to poor image quality rather than bad theory. The researchers are now looking for signals in on-the-ground measurements of vegetation changes.

“These things aren’t going to be foolproof. There will be false positives and false negatives, and people need to be aware of that,” said Carpenter. “There’s still a great deal of basic research going on to understand the indicators better. We’re still in the early days. But why not try? The alternative is to get repeatedly blindsided. The alternative is not appealing.”

Time magazine in Is There a Climate-Change Tipping Point? quotes co-author Steve Carpenter:

So, how do we know that change is at hand? The Nature researchers noticed one potential signal: the sudden variance between two distinct states within one system, known by the less technical term squealing. In an ecological system like a forest, for example, squealing might look like an alternation between two stable states — barren versus fertile — before a drought takes its final toll on the woodland and transforms it into a desert, at which point even monsoons won’t bring the field back to life. Fish populations seem to collapse suddenly as well — overfishing causes fluctuations in fish stocks until it passes a threshold, at which point there are simply too few fish left to bring back the population, even if fishing completely ceases. And even in financial markets, sudden collapses tend to be preceded by heightened trading volatility — a good sign to pull your money out of the market. “Heart attacks, algae blooms in lakes, epileptic attacks — every one shows this type of change,” says Carpenter. “It’s remarkable.” 

In climate terms, squealing may involve increased variability of the weather — sudden shifts from hot temperatures to colder ones and back again. General instability ensues and, at some point, the center ceases to hold. “Before we reached a climate tipping point we’d expect to see lots of record heat and record cold,” says Carpenter. “Every example of sudden climate change we’ve seen in the historical record was preceded by this sort of squealing.”

The hard part will be putting this new knowledge into action. It’s true that we have a sense of where some of the tipping points for climate change might lie — the loss of Arctic sea ice, or the release of methane from the melting permafrost of Siberia. But that knowledge is still incomplete, even as the world comes together to try, finally, to address the threat collectively. “Managing the environment is like driving a foggy road at night by a cliff,” says Carpenter. “You know it’s there, but you don’t know where exactly.” The warning signs give us an idea of where that cliff might be — but we’ll need to pay attention.

Reflections on urban resilience

Two recent reflections on resilience in cities, which use different definitions of resilience than the resilience alliance.  The first focuses on resilience as social trust and while the second on resilience as persistence.

Arjun Appadurai on the Immanent Frame writes: Is Mumbai’s resilience endlessly renewable?

Many well-meaning observers have stressed the “resilience”, the mutual generosity, the quotidian heroism and the remarkable resistance of Mumbaikars to jump to quick conclusions or hasty reprisals. I too congratulate and celebrate these facts. But I fear that all resilience is historically produced. And what history gives, history can take away. Yes, we are all Mumbaikars now. But in a world that links Mumbai, Kashmir, Karachi, Madrid, Peshawar, London, Wall Street, Washington and Faridkot, that is not necessarily a source of comfort. Resilience is a public resource. But, unlike terror, it is not indefinitely renewable.

In the Detroit Free Press columnist Sarah Webster quotes Steve Carpenter on resilience to explain why Detroit will come back in Detroit: Not a town of quitters:

If you’re from Detroit, you probably already know how much resilience has been fused into your bones.

This town is full of it.

In a YouTube video (Watch Carpenter explain it )posted by the Stockholm Resilience Centre, Professor Stephen Carpenter, who specializes in ecosystems at the University of Wisconsin, said resilience explains how things can “change and persist at the same time.”

“A resilient system could be able to withstand a shock without losing its basic functions,” he said. “A resilient system is able to transform to a different way of life when the current way of life is no longer feasible.”

But where resilience comes from – and why some people get it, while others don’t – isn’t a subject that’s very well understood. …

Like much of America, Detroit is full of immigrants. Those who came to Detroit, however, came to work in the factories at a time when factories weren’t so clean or safe, and there was a lot of competition for those $5 a day jobs. Factory work was for thick-skinned men who could breathe smoke, slog away near blazing fire pits of molten steel and assemble heavy car parts with their bare hands.

Wimps were not needed. Only the strong survived.

As somebody who came to Detroit just a decade ago, it seems to me that children of these immigrants – many of whom still work today in Detroit’s factories, or as engineers, designers and managers throughout the region – still know how to fight for what they believe in. And they seem to know that sometimes fights are best won in the final rounds, not in the early ones.

From time to time, I think it’s a good idea to remind folks what makes them so special — especially when they’re feeling down, as Detroit seems to be lately.

So, Detroit, know this: This is not a town of quitters.

And it’s why I feel so sure that Detroit, and its auto industry, will make a big comeback someday.

Avoiding regime shifts is difficult

Conservation magazine’s Journal Watch Online returns from a long hiatus to report on an interesting new paper on the problems of detecting regime shifts by resilience researchers Oonsie Biggs, Steve Carpenter, and W.A. “Buz” Brock (2009. Turning back from the brink: Detecting an impending regime shift in time to avert it. PNAS DOI 10.1073/pnas.0811729106).  They write:

Like the stock market, ecosystems can dramatically collapse. But how much advance notice is needed to prevent a natural system meltdown? A paper in Proceedings of the National Academy of Sciences says the answer might be several decades, which means today’s warning systems don’t detect changes nearly far enough in advance.

Using Northern Wisconsin’s sport fishery as a model, University of Wisconsin researchers determined when an ecosystem reaches the brink of an unstoppable shift, then estimated when recovery efforts must start in order to avert collapse. They found that some rapid actions only need short timetables; angling cuts can prevent permanent damage to fisheries even if they’ve been declining for ten years. But other changes, like restoring habitat after too much shoreline development, must start as many as 45 years before ecological health indicators start wobbling.

The problem is, most indicators in today’s early-warning systems can’t detect serious shifts that far out. Even if they could, it might still take policymakers years to enact recovery schemes. Which leads the authors to plea for indicators that work on a longer horizon, and for policy makers to move swiftly once scientists buy them some time.

Steve Carpenter on Black Swans

Ecologist Steve Carpenter follows up on Don Ludwig’s comments on Nassim Nicholas Taleb‘s book The Black Swan:

Both of Taleb’s books are highly entertaining. But he over-reaches. There are some odd mistakes. For example, he makes much of a supposed kink in the integral of the Student-t distribution, (where tail probability declines linearly with deviation from the mean) but if you compute the integral using R software there is no kink — so Taleb evidently made a mistake.

Based on web sites, Taleb made his fortune using a kind of option trade. He purchases only options to buy securities at a certain price during a specified time window in the future. So if the security is trading above Taleb’s price, he buys it and then immediately sells at the market price, thereby making a profit. He says that his life involves long periods of time watching while nothing happens and his options to buy expire. But once in a great while he makes a killing. This is exactly like predators who specialize on very large prey, or fishing for big game fish, or hunting for rare but big game animals.

His writings have done a lot to publicize the importance of huge rare events. I think this is a good thing. But also he over-reaches. In some recent interviews he seems to be gloating over the current economic collapse. And (according to economist colleagues) some economists see his ideas as rather routine. Yet he is a provocative and entertaining writer; if sales measure impact he has made a difference.

To me, the most novel feature of the current ongoing collapse is the coincidence of huge shocks with apparently different triggers. Who would have thought that an epidemic of bad loans in America, steep ramp of energy prices, and biofuels tightening the link of energy to food prices would coincide, against a backdrop of lower economic firewalls between countries and increasingly intense food limitation of the human population, with almost no scope for growth of the food supply. It’s a wonderland for testing resilience ideas and a global tragedy, all at the same time.

For a recent talk I re-analyzed a bunch of information from the Millennium Assessment, to try to figure out if humanity had any chance at all for making it through the next few decades.

If everyone shifts trophic status to roughly herbivore level, and we educate all the world’s women to secondary level, we have a chance.

The difference between 12 billion and 9 billion people in 2050 is one child per woman. If all the world’s women were educated to secondary level, fertility would drop by about 1.7 children per woman. And we can probably feed 9 billion herbivorous people, if we can maintain the crop diversity of the major grain crops high enough to avoid catastrophic disease outbreaks.

Energy needs for agriculture and climate change could make it pretty hard to achieve the rosy scenario; climate heating, more variable precipitation and sea level rise have bad implications for agriculture. So the rosy scenario itself may be way out on the tail of the distribution. And what will happen to relations among people as the going gets rough? Human conflict can wreck agriculture. What are the chances that no one will use nuclear weapons? Even a few nukes would take out huge areas of arable land for millennia. And, as Will Rogers said about land, they ain’t makin’ any more of it. A Taleb-like fat tail breakdown seems not so implausible.