Regime Shifts

Climate Change May Transform Fire Regime in Tundra

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arctic tundraPhilip Higuera and collaborators suggests that based on paleo-ecological analysis of past fire regimes, climate change could lead to abrupt shifts in tundra fire frequency as climate change vegetation shifts from herb to shrub dominated tundra.

In their article (Higuera PE, Brubaker LB, Anderson PM, Brown TA, Kennedy AT & Hu FS. 2008 Frequent fires in ancient shrub tundra: implications of paleorecords for Arctic environmental change. PLoS ONE DOI: 10.1371/journal.pone.0001744) the authors write:

… paleorecords from northcentral Alaska imply that ongoing shrub expansion and climate warming will result in greater burning within northern tundra ecosystems. The geographic extent of fire-regime changes could be quite large, as shrubs are expected to expand over the next century in both herb and low shrub tundra ecosystems, which comprise 67% of circumpolar Arctic tundra [10], [15] (Fig. 1). Over this same period, annual temperatures in the Arctic are projected to increase between 3–5°C over land, lengthening the growing season and likely decreasing effective moisture (in spite of increased summer precipitation) [8]. How long might it take for the current shrub expansion to trigger a significant change in fire frequencies? Within the chronological limitations of our records, past shrub expansion and fire-regime changes at each site occurred within a few centuries (Fig. 2). The duration of this shift is consistent with the estimated rate of shrub expansion within a large area of northern Alaska [0.4% yr−1 for ca 200,000 km2; 10]. Based on a simple logistic growth model and the assumption of a constant expansion rate, Tape et al. [10] hypothesize that the ongoing shrub expansion in this region started roughly 125 years ago and should reach 100% of the region in another 125 years. Thus, if fuels and low effective moisture are major limiting factors for tundra fires, we predict that fire frequencies will increase across modern tundra over the next several centuries.

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Despite these uncertainties, Alaskan paleorecords provide clear precedence of shrub-dominated tundra sustaining higher fire frequencies than observed in present-day tundra. The future expansion of tundra shrubs [10], [16] coupled with decreased effective moisture [8] could thus enhance circumpolar Arctic burning and initiate feedbacks that are potentially important to the climate system. Feedbacks between increased tundra burning and climate are inherently complex [3]–[5], but studies of modern tundra fires suggest the possibility for both short- and long-term impacts from (1) increased summer soil temperatures and moisture levels from altered surface albedo and roughness [24], and (2) the release soil carbon through increased permafrost thaw depths and the consumption of the organic layer [24], [25]. Given the importance of land-atmosphere feedbacks in the Arctic [26]–[28], the precedence of a fire-prone tundra biome should motivate further research into the controls of tundra fire regimes and links between tundra burning and the climate system.

Climate driven changes in vegetation cover across the most northern land surfaces on the planet will likely result in more carbon-releasing fires, according to a study published this week in PLoS ONE. Philip Higuera, currently at Montana State University, and colleagues examined charcoal and pollen samples from Alaskan lakes, which provide a historical record of plant composition and fire frequency between 14000 and 10000 years ago. Back then, the tundra was dominated by extensive thickets of resin birch Betula glandulosa, and the warming climate is likely to see its widespread return to areas currently occupied by somewhat less flammable herbs. The mass of tangled, resin-laden twigs could turn the area into a tinderbox, with the double whammy that such fires encourage vigorous birch regrowth, making it prone to further blazes. The likely consequence is that another source of carbon dioxide will enter the scene, as vegetation and long-frozen soil go up in smoke.

via SCB’s Journal Watch Online

Visualization

Global and National Malaria Maps

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Malaria Atlas Project used national reports, ecological and epidemological models to create a new global map of P. falciparum malaria risk. Guerra et al 2008 PLoS Medicine estimate that 2.37 billion people live in areas at risk of P. falciparum transmission. However, almost a billion people of those people live in areas with only episodic or very low risk of malaria exposuire suggesting there in substantial possibility of eliminating malaria from these areas. Almost all areas with high risk are in Africa.

Below is a small version of their global map of P. Falciparium (the most dangerous species) of Malaria risk for 2007:global malaria map

Their maps can be viewed in google earth, as country maps, or as as an ArcGrid file at 0.1 degree spatial resolution.

Adaptation, Cities

Carbon Neutral Universities

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Metropolis Magazine writes about the maturing and deepening of the university campus sustainability in Carbon Neutral U:

Higher education has emerged as a thrilling proving ground for a sustainable society. Schools of all statures and sizes—from the Ivies to red-state community colleges—are making the most of their fiefdoms, leveraging their educated and politically engaged populations, long-term outlooks, and self-managed (the often significant) physical footprints to make substantial changes. But with those changes comes a surprising reversal in academe’s typical stance: the mechanics of the campus are occupying the brightest spotlight. Students, administrators, and faculty are obsessing over the cleaning products the janitors use, how dining-hall potatoes are grown, and which dorms consume the least energy. Infrastructure is hot—hotter arguably than research or teaching about sustainability. It is as if the ivory tower has looked out to the world and seen a choking planet, and its first response is to look inward again at its own activities—building designs, power plants, and transportation systems. …

Schools are also looking to one another for help, increasingly collaborating in realms where they have traditionally competed. “There’s long been an incredible amount of peer benchmarking across higher education, but that’s not the same as collaboration,” says Mark Orlowski, executive director of the Sustainable Endowments Institute, the publisher of the College Sustainability Report Card 2008, which evaluated 200 schools on their environmental activities. “Collaboration, while quite widespread in the academic side of the university, has been less prevalent in operations,” he adds.
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The range of projects is staggering. After a decade of bring-your-own-coffee-mug student environmentalism, the opening salvo of a new, more glamorous era in campus sustainability came in 2001, when the daughter of famed Berkeley, California, chef Alice Waters enrolled as a freshman at Yale. Waters’s initial disgust at the cafeteria steam tables evolved into the Yale Sustainable Food Project, which today manages an organic campus farm, directs a sustainable dining program, and serves as the base for a series of academic classes. It’s also been a lightning rod for PR—“A Dining Hall Where Students Sneak In,” crowed the New York Times—and dozens of schools have launched similar programs. More recently, as campuses have turned their attention to carbon reduction, no detail is too small: dorms are providing laundry racks for no-energy clothes drying, offering free bike maintenance as well as shared bikes, encouraging students to disconnect their dorm appliances over vacations, and recycling their organic potato French fry grease into biodiesel fuel for campus buses.

… For the cadre of campus sustainability coordinators, “creating a culture of sustainability” is one of the measures of success. The administrative structures for sustainability offices vary school by school, with some coordinators reporting through facilities, some through the provost or president’s offices, and some through both. But they all have the mandate to bridge the university’s operational initiatives to its teaching and research—to make the nuts and bolts count toward the big teachable ideas. With the wave of interest sweeping the students and faculty, new projects are coming from everywhere. The sustainability coordinator plays traffic cop, diplomat, and “facilitator.” As Yale’s Newman puts it, “What’s so fascinating about these positions is that we don’t directly oversee any of these functions. We have no power to do any of it. Our role is to be a sustainability generalist and then to develop questions and frameworks to understand how these systems work independently and together—so that, in the aggregate, does it lead to a sustainable Yale?”

General

Peverse Wildlife Conservation

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The Chernobyl disaster created a large poisoned involuntary park. Similarly, mercury pollution (as well as other persistent organic pollutants) may perversely help wildlife conservation by reducing hunting (but damaging the health and livelihoods of those who depend upon the hunting of animals they have little to do with poisoning). The New York Times writes about how Mercury Taint Divides a Japanese Whaling Town:

For years, Western activists have traveled to this remote port to protest the annual dolphin drive. And for years, local fishermen have ignored them, herding the animals into a small cove and slashing them until the tide flows red. But now, a new menace may succeed where the activists have failed: mercury.

…Dolphin meat is a local delicacy, served raw as sashimi or boiled with soy sauce. People here are used to the international scorn that accompanies the dolphin hunt and have closed ranks in the face of rising outrage — until now.Last June, laboratory tests showed high levels of mercury in dolphin and pilot whale, a small whale that resembles a dolphin, that were caught and sold here. Schools stopped serving pilot whale meat for lunch, and some local markets removed it as well as dolphin from their shelves.

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General

Banana Political Ecology

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Bananas are one of the world’s main food crops (4th in economic value) with over 100 million tons being produced per year, most of these bananas are a consumed in the tropics, but 15% are exported and are key exports of many poor countries. Daniel Kurtz-Phelan in the New York Times Book Review on Peter Chapman‘s book Bananas: How the United Fruit Company Shaped the World:

For much of the 20th century, the American banana company United Fruit dominated portions of almost a dozen countries in the Western Hemisphere. It was, Peter Chapman writes in “Bananas,” his breezy but insightful history of the company, “more powerful than many nation states … a law unto itself and accustomed to regarding the republics as its private fiefdom.” United Fruit essentially invented not only “the concept and reality of the banana republic,” but also, as Chapman shows, the concept and reality of the modern banana. “If it weren’t for United Fruit,” he observes, “the banana would never have emerged from the dark, then arrived in such quantities as to bring prices that made it available to all.”…

Throughout all of this, United Fruit defined the modern multinational corporation at its most effective — and, as it turned out, its most pernicious. At home, it cultivated clubby ties with those in power and helped pioneer the modern arts of public relations and marketing. (After a midcentury makeover by the “father of public relations,” Edward Bernays, the company started pushing a cartoon character named Señorita Chiquita Banana.) Abroad, it coddled dictators while using a mix of paternalism and violence to control its workers. “As for repressive regimes, they were United Fruit’s best friends, with coups d’état among its specialties,” Chapman writes. “United Fruit had possibly launched more exercises in ‘regime change’ on the banana’s behalf than had even been carried out in the name of oil.”

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Ecosystem services, Regime Shifts

Coral Reefs in the Anthropocene

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Plos OneIn a commentary Shifting Baselines, Local Impacts, and Global Change on Coral Reefs in PLoS Biology coral reef ecologists Nancy Knowlton and Jeremy Jackson write:

Imagine trying to understand the ecology of tropical rainforests by studying environmental changes and interactions among the surviving plants and animals on a vast cattle ranch in the center of a deforested Amazon, without any basic data on how the forest worked before it was cleared and burned. The soil would be baked dry or eroded away and the amount of rainfall would be greatly decreased. Most of the fantastic biodiversity would be gone. The trees would be replaced by grasses or soybeans, the major grazers would be leaf-cutter ants and cattle, and the major predators would be insects, rodents, and hawks. Ecologists could do experiments on the importance of cattle for the maintenance of plant species diversity, but the results would be meaningless for understanding the rainforest that used to be or how to restore it in the future.

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This lack of a baseline for pristine marine ecosystems is particularly acute for coral reefs, the so-called rainforests of the sea, which are the most diverse marine ecosystems and among the most threatened [4–8]. Most of the world’s tropical coastal oceans are so heavily degraded locally that “pristine” reefs are essentially gone, even if one ignores changes associated with already rising temperatures and acidity [3]. Most modern (post-SCUBA) ecological studies have focused on reef ecosystems that are moderately to severely degraded, and we have a much better understanding of transitions between human-dominated and collapsed reefs than between human-dominated and quasi-pristine reefs.

Knowlton and Jackson’s essay is a comment on an article in PLoS One Baselines and Degradation of Coral Reefs in the Northern Line Islands by Stuart Sandin and others that describes a large scale marine community assessment across a gradient of human dominated to relatively little impacted reefs in the Pacific. The study found that large predatory fish and reef-building organisms dominated the reefs around unpopulated islands, but around populated islands the reefs were dominated by small planktivorous fishes and fleshy algae. The reefs around populated islands exhibited more coral disease and less coral recruitment, suggesting that protection from overfishing and pollution may increase the resilience of coral reefs. The authors write:

Thus, local protection from overfishing and pollution may enhance ecosystem resilience to warm episodes and coral bleaching that result from global warming. To test this we need to determine how do coral recruitment, growth, and survivorship respond to changes in local community structure due to fishing, and how do these responses interact with episodes of warming measured by DHW. We also need to determine how fish productivity, i.e., the key currency of fisheries management, varies with changes in food web structure such as those observed between Kingman and Kiritimati. The only way to answer these questions is by investigation of reefs like the northern Line Islands that have remained remarkably intact in comparison to the global norm. They are among the only baselines that remain.

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Ecological Economics, Networks, Regime Shifts

Ecology for bankers

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In Feb 21 2008 Nature, ecologists Robert May, Simon Levin, and George Sugihara write about how ecological thinking can be used to illuminate financial dynamics in their commentary Complex systems: Ecology for bankers:

‘Tipping points’, ‘thresholds and breakpoints’, ‘regime shifts’ — all are terms that describe the flip of a complex dynamical system from one state to another. For banking and other financial institutions, the Wall Street Crash of 1929 and the Great Depression epitomize such an event. These days, the increasingly complicated and globally interlinked financial markets are no less immune to such system-wide (systemic) threats. Who knows, for instance, how the present concern over sub-prime loans will pan out?

Well before this recent crisis emerged, the US National Academies/National Research Council and the Federal Reserve Bank of New York collaborated on an initiative to “stimulate fresh thinking on systemic risk”. The main event was a high-level conference held in May 2006, which brought together experts from various backgrounds to explore parallels between systemic risk in the financial sector and in selected domains in engineering, ecology and other fields of science. The resulting report was published late last year and makes stimulating reading.

Catastrophic changes in the overall state of a system can ultimately derive from how it is organized — from feedback mechanisms within it, and from linkages that are latent and often unrecognized. The change may be initiated by some obvious external event, such as a war, but is more usually triggered by a seemingly minor happenstance or even an unsubstantial rumour. Once set in motion, however, such changes can become explosive and afterwards will typically exhibit some form of hysteresis, such that recovery is much slower than the collapse. In extreme cases, the changes may be irreversible.

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Two particularly illuminating questions about priorities in risk management emerge from the report. First, how much money is spent on studying systemic risk as compared with that spent on conventional risk management in individual firms? Second, how expensive is a systemic-risk event to a national or global economy (examples being the stock market crash of 1987, or the turmoil of 1998 associated with the Russian loan default, and the subsequent collapse of the hedge fund Long-Term Capital Management)? The answer to the first question is “comparatively very little”; to the second, “hugely expensive”.

Adaptation

Self-organized traffic safety

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The UK County Surveyor’s Society Transport Futures group has just published a report Travel is Good that considers how to deal with problems likely to be encountered in transport over the next 20 years. They recommend increasing uncertainty and allowing the self-organization of multiple forms of traffic to increase safety, along with congestion pricing cars, and preparing for climate change.

This report is part of a trend of European traffic planners moving away from signs and regulations to increase traffic safety. Rather than legislating space for cars they are requiring drivers, pedestrians, and cyclists to think about what they are doing rather than obeying signs. This approach appears to fit many resilience principles by encouraging many small disturbances makes the overall system more resilient (see: Traffic Safety: Regulation vs. Self-Organization).

The UK’s Times Online describes the report in their article How stripping the streets of traffic lights and signs may be a life saver:

Redesigning roads to leave drivers and pedestrians uncertain about who has priority will save lives, according to a report by Britain’s most senior transport officials. The move would automatically cut traffic speed without the need for cameras, they say.

Barriers and signs such as railings, kerbs, traffic lights and white lines cause crashes because people assume they will keep them safe and therefore fail to focus on what other road users are doing. Giving drivers less information by removing signs will encourage them to slow down to negotiate a safer course along high streets and across junctions.

The report by the County Surveyors’ Society, which represents local authority directors responsible for most roads in England and Wales, recommends a revolution in road design. It calls for widespread adoption of the concept of “shared space”, pioneered in the Netherlands and better known in Britain as “naked streets”.

It says: “Paradoxically, creating barriers and divisions may worsen safety because drivers and riders feel more confident and speed up, despite the limitations on the speed at which the human mind can take in the amount of information now displayed on our roads. The human response to increased in-car and on-road safety may be to increase risky behaviour.

…Ben Hamilton Baillie, a transport consultant who contributed to the report, said it marked acceptance at the highest levels of shared space principles that five years ago were considered outlandish. Roads in Bath, Ashford in Kent, and Ancoats in Manchester are being converted to shared space. Work will begin next year on removing kerbs and giving pedestrians greater priority on Exhibition Road in West London