Greenlash

How Salmon Farming Endangers Salmon

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From Society for Conservation Biology’s Journal Watch Online:

Long-held suspicions that fish farms act as disease reservoirs for wild populations are well founded, according to findings published this week in Science. University of Alberta mathematical biologist Marty Krkošek and colleagues show that outbreaks of salmon lice Lepeophtheirus salmonis among wild pink salmon Oncorhynchus gorbuscha populations — the direct result of infestations within the open-net aquaculture pens the juveniles must swim past on their migration to the sea — can bring virtual extinction in just four generations. The pressure wild stocks are placed under by the disease risk from fish farms is much greater than that caused by over-exploitative harvesting: the very factor that prompted aquaculture in the first place. It’s surely time for a re-think on fish farming. Source: Krkošek M, Ford JS, Morton A, Lele S, Myers RA & Lewis MA (2007) Declining wild salmon populations in relation to parasites from farm salmon. Science DOI: 10.1126/science.1148744

Also see article in New York Times which quotes:

Ray Hilborn, a fisheries biologist from the University of Washington who was not involved in the study but is familiar with its findings, called the data persuasive and said they raised “serious concerns about proposed aquaculture for other species, such as cod, halibut and sablefish.”

“These high-density fish farms are natural breeding grounds for pathogens,” not necessarily limited to sea lice, he said in an interview. Dr. Hilborn noted, however, that the study involved pink salmon, not species like sockeye or chinook, which are usually larger and presumably less vulnerable to sea lice. Pink salmon are the most abundant salmon species in the northern Pacific.

Ecological Economics, Regime Shifts

How to deal with uncertainty in climate change economics

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From the economist Martin L. Weitzman‘s website, a new draft paper On Modeling and Interpreting the Economics of Catastrophic Climate Change(pdf).  He proposes a method for including unlikely but extreme events (fat tails) in cost-benefit analyses, such as the uncertainty surrounding climate sensitivity.  Considering the possibility of such events can completely change the results of an analysis, and favour action as a type of catastrophe insurance.

Abstract: Using climate change as a prototype example, this paper analyzes the implications of structural uncertainty for the economics of low-probability high-impact catastrophes. The paper is an application of the idea that having an uncertain multiplicative parameter, which scales or amplifes exogenous shocks and is updated by Bayesian learning, induces a critical tail fattening of posterior-predictive distributions. These fattened tails can have very strong implications for situations (like climate change) where a catastrophe is theoretically possible because prior knowledge cannot place sufficiently narrow bounds on overall damages. The essence of the problem is the difficulty of learning extreme-impact tail behavior from finite data alone. At least potentially, the ináuence on cost-benefit analysis of fat-tailed uncertainty about climate change, coupled with extreme unsureness about high-temperature damages, can outweigh the influence of discounting or anything else.

The paper concludes:

In principle, what might be called the catastrophe-insurance aspect of such a fat-tailed unlimited-exposure situation, which can never be fully learned away, can dominate the social-discounting aspect, the pure-risk aspect, or the consumption-smoothing aspect. Even if this principle in and of itself does not provide an easy answer to questions about how much catastrophe insurance to buy (or even an easy answer in practical terms to the question of what exactly is catastrophe insurance buying for climate change or other applications), I believe it still might provide a useful way of framing the economic analysis of catastrophes.

Regime Shifts

Arctic sea ice: is it tipped yet?

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RealClimate reports from the AGU about Arctic sea ice: is it tipped yet?

The summer of 2007 was apocalyptic for Arctic sea ice. The coverage and thickness of sea ice in the Arctic has been declining steadily over the past few decades, but this year the ice lost an area about the size of Texas, reaching its minimum on about the 16th of September. Arctic sea ice seems to me the best and more imminent example of a tipping point in the climate system. A series of talks aimed to explain the reason for the meltdown.

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The disappearance of the ice was set up by warming surface waters and loss of the thicker multi-year ice in favor of thinner single-year ice. But the collapse of ice coverage this year was also something of a random event. This change was much more abrupt than the averaged results of the multiple IPCC AR4 models, but if you look at individual model runs, you can find sudden decreases in ice cover such as this. In the particular model run which looks most like 2007, the ice subsequently recovered somewhat, although never regaining the coverage before the meltback event.

So what is the implication of the meltback, the prognosis for the future? Has the tipping point tipped yet? When ice melts, it allows the surface ocean to begin absorbing sunlight, potentially locking in the ice-free condition. Instead of making his own prognosis, Overland allowed the audience to vote on it. The options were

* A The meltback is permanent
* B Ice coverage will partially recover but continue to decrease
* C The ice would recover to 1980’s levels but then continue to decline over the coming century

Options A and B had significant audience support, while only one brave soul voted for the most conservative option C. No one remarked that the “skeptic” possibility, that Arctic sea ice is not melting back at all, was not even offered or asked for. Climate scientists have moved beyond that.

For more coverage see Nature’s Great Beyond.

Ecosystem services, Visualization

Mapping the Anthropocene: Anthropegenic Biomes

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Humanity is now a geological force reshaping the Earth’s surface, atmosphere, and biogeochemistry. This reality has lead Earth System Scientists to argue that we are living in a new geological era – the Anthropocene.

Recently Navin Ramankutty, a colleague of mine here at McGill, and Erle Ellis, from the University of Maryland, have developed a map of the world the acknowledges that we are in the Anthropocene by identifying the anthropogenic biomes that are currently found in the world.

Anthro biomes in E NA from google maps

anthro biomes legend

They define an anthropogenic biome as:

Anthropogenic biomes describe globally-significant ecological patterns within the terrestrial biosphere caused by sustained direct human interaction with ecosystems, including agriculture, urbanization, forestry and other land uses. Conventional biomes, such as tropical rainforests or grasslands, are based on global vegetation patterns related to climate. Now that humans have fundamentally altered global patterns of ecosystem form, process, and biodiversity, anthropogenic biomes provide a contemporary view of the terrestrial biosphere in its human-altered form. Anthropogenic biomes may also be termed “anthromes” to distinguish them from conventional biome systems, or “human biomes” (a simpler but less precise term).

The maps can be viewed as PDFs, or interactively using Google Maps or Google Earth. Links to these files can be found in the article in their article Anthropogenic biome maps in the Enclyopedia of the Earth.

The McGill website has a a ten-minute interview with Prof. Ramankutty, and both authors wrote a follow up article Conserving Nature in an Anthropogenic Biosphere on Earth Portal, where they write:

If we say that most ecosystems are now anthropogenic, does this devalue the conservation and protection of “Nature”? Have we given those who oppose conservation a new tool to eliminate conservation altogether? Though this was never our intention, it seems to be a potential repercussion of our work.

Here is our defense.

On the one hand, we are convinced, as are many, that it is time to give up on the “protecting fragile nature” approach to conserving a desirable environment. Managing nature in preserves and leaving the rest of the world to its own devices does not and will not achieve our objectives.
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It is our hope that in this century we can improve our environmental governance by building a citizen’s “morality of nature” through education and participation, rather than by fear of the consequences. Indeed, there are many indications already that we are getting better at managing the environment, and that the regenerative powers of nature are cleaning our rivers, regrowing our forests, and healing the ozone layer.

We are already in the driver’s seat. If our collective desire leads us to conserve, preserve, and restore “Nature”, we will all be the better off for this. But managing nature as if everything we touch is destroyed just will not get us to where we want to go.

They describe their map in the paper:

Ellis, E. C., and N. Ramankutty. In Press. Putting people in the map: anthropogenic biomes of the world. Frontiers in Ecology and the Environment 6:XXX. doi:10.1890/070062 . (which is available online before publication).

Greenlash

David Quammen on Emerging Infectious Disease

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From National Geographic

David Quammen writes about emerging infectious diseases in National Geographic (Oct 2007):

Infectious disease is all around us. Infectious disease is a kind of natural mortar binding one creature to another, one species to another, within the elaborate edifices we call ecosystems. It’s one of the basic processes that ecologists study, including also predation, competition, and photosynthesis. Predators are relatively big beasts that eat their prey from outside. Pathogens (disease-causing agents, such as viruses) are relatively small beasts that eat their prey from within. Although infectious disease can seem grisly and dreadful, under ordinary conditions it’s every bit as natural as what lions do to wildebeests, zebras, and gazelles.

But conditions aren’t always ordinary.

Just as predators have their accustomed prey species, their favored targets, so do pathogens. And just as a lion might occasionally depart from its normal behavior—to kill a cow instead of a wildebeest, a human instead of a zebra—so can a pathogen shift to a new target. Accidents happen. Aberrations occur. Circumstances change and, with them, opportunities and exigencies also change. When a pathogen leaps from some nonhuman animal into a person, and succeeds there in making trouble, the result is what’s known as a zoonosis.

The word zoonosis is unfamiliar to most people. But it helps clarify the biological reality behind the scary headlines about bird flu, SARS, other forms of nasty new disease, and the threat of a coming pandemic. It says something essential about the origin of HIV. It’s a word of the future, destined for heavy use in the 21st century.

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Close contact between humans and other species can occur in various ways: through killing and eating of wild animals (as in Mayibout II), through caregiving to domestic animals (as in Hendra), through fondling of pets (as with monkeypox, brought into the American pet trade by way of imported African rodents), through taming enticements (feeding bananas to the monkeys at a Balinese temple), through intensive animal husbandry combined with habitat destruction (as on Malaysian pig farms), and through any other sort of disruptive penetration of humans into wild landscape—of which, needless to say, there’s plenty happening around the world. Once the contact has occurred and the pathogen has crossed over, two other factors contribute to the possibility of cataclysmic consequences: the sheer abundance of humans on Earth, all available for infection, and the speed of our travel from one place to another. When a bad new disease catches hold, one that manages to be transmissible from person to person by a handshake, a kiss, or a sneeze, it might easily circle the world and kill millions of people before medical science can find a way to control it.

But our safety, our health, isn’t the only issue. Another thing worth remembering is that disease can go both ways: from humans to other species as well as from them to us. Measles, polio, scabies, influenza, tuberculosis, and other human diseases are considered threats to non-human primates. The label for those infections is anthropozoonotic. Any of them might be carried by a tourist, a researcher, or a local person, with potentially devastating impacts on a tiny, isolated population of great apes with a relatively small gene pool, such as the mountain gorillas of Rwanda or the chimps of Gombe. 

Ecological Economics, Ecosystem services

Food prices rising due increases in meat consumption and biofuels

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The Economist (Dec 6th 2007) writes about how global agricultural prices are Cheap no more:

economist on food prices

…what is most remarkable about the present bout of “agflation” is that record prices are being achieved at a time not of scarcity but of abundance. According to the International Grains Council, a trade body based in London, this year’s total cereals crop will be 1.66 billion tonnes, the largest on record and 89m tonnes more than last year’s harvest, another bumper crop. That the biggest grain harvest the world has ever seen is not enough to forestall scarcity prices tells you that something fundamental is affecting the world’s demand for cereals.

Two things, in fact. One is increasing wealth in China and India. This is stoking demand for meat in those countries, in turn boosting the demand for cereals to feed to animals. The use of grains for bread, tortillas and chapattis is linked to the growth of the world’s population. It has been flat for decades, reflecting the slowing of population growth. But demand for meat is tied to economic growth (see chart 1) and global GDP is now in its fifth successive year of expansion at a rate of 4%-plus.

Higher incomes in India and China have made hundreds of millions of people rich enough to afford meat and other foods. In 1985 the average Chinese consumer ate 20kg (44lb) of meat a year; now he eats more than 50kg. China’s appetite for meat may be nearing satiation, but other countries are following behind: in developing countries as a whole, consumption of cereals has been flat since 1980, but demand for meat has doubled.

Not surprisingly, farmers are switching, too: they now feed about 200m-250m more tonnes of grain to their animals than they did 20 years ago. That increase alone accounts for a significant share of the world’s total cereals crop. Calorie for calorie, you need more grain if you eat it transformed into meat than if you eat it as bread: it takes three kilograms of cereals to produce a kilo of pork, eight for a kilo of beef. So a shift in diet is multiplied many times over in the grain markets. Since the late 1980s an inexorable annual increase of 1-2% in the demand for feedgrains has ratcheted up the overall demand for cereals and pushed up prices.

Because this change in diet has been slow and incremental, it cannot explain the dramatic price movements of the past year. The second change can: the rampant demand for ethanol as fuel for American cars. In 2000 around 15m tonnes of America’s maize crop was turned into ethanol; this year the quantity is likely to be around 85m tonnes. America is easily the world’s largest maize exporter—and it now uses more of its maize crop for ethanol than it sells abroad.

Ethanol is the dominant reason for this year’s increase in grain prices. It accounts for the rise in the price of maize because the federal government has in practice waded into the market to mop up about one-third of America’s corn harvest. A big expansion of the ethanol programme in 2005 explains why maize prices started rising in the first place.

Ethanol accounts for some of the rise in the prices of other crops and foods too. Partly this is because maize is fed to animals, which are now more expensive to rear. Partly it is because America’s farmers, eager to take advantage of the biofuels bonanza, went all out to produce maize this year, planting it on land previously devoted to wheat and soyabeans. This year America’s maize harvest will be a jaw-dropping 335m tonnes, beating last year’s by more than a quarter. The increase has been achieved partly at the expense of other food crops.

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Guess who loses
According to the World Bank, 3 billion people live in rural areas in developing countries, of whom 2.5 billion are involved in farming. That 3 billion includes three-quarters of the world’s poorest people. So in principle the poor overall should gain from higher farm incomes. In practice many will not. There are large numbers of people who lose more from higher food bills than they gain from higher farm incomes. Exactly how many varies widely from place to place.

Among the losers from higher food prices are big importers. … some of the poorest places in Asia (Bangladesh and Nepal) and Africa (Benin and Niger) also face higher food bills. Developing countries as a whole will spend over $50 billion importing cereals this year, 10% more than last.

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In every country, the least well-off consumers are hardest hit when food prices rise. This is true in rich and poor countries alike but the scale in the latter is altogether different. As Gary Becker, a Nobel economics laureate at the University of Chicago, points out, if food prices rise by one-third, they will reduce living standards in rich countries by about 3%, but in very poor ones by over 20%.

Ecosystem services, Visualization

Farming the World for Food and Feed

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Croplands and pastures cover about a 1/3 of the Earth’s ice free surface. Foley et al in their PNAS commentary Our share of the planetary pie illustrate the uses of this agricultural production. Their map shows the percentage of crop NPP used to produce food that humans consume directly (blue) or indirectly in processed products (orange-red). The majority of the nonfood portion is feed for livestock, but also includes fiber or luxury crops, such as cotton and coffee. Note the differences between agriculture is rich (feed for livestock) and poor countries (food).

Foley et al PNAS Fig (http://www.pnas.org/cgi/content/full/104/31/12585)

Click on map for a larger verison.

The map is based on data from:

Monfreda, C., N. Ramankutty, and J. A. Foley (In Press), Farming the Planet. 2: The Geographic Distribution of Crop Areas, Yields, Physiological Types, and NPP in the Year 2000, Global Biogeochemical Cycles, doi:10.1029/2007GB002947.

Ecological Economics, General, Greenlash

Stern: In Bali the rich must pay

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Nicholas Stern, former chief economist of the World Bank and who led the Stern review on the economics of climate change, writes in the Guardian (Nov 30, 2007), that in Bali the rich must pay to produce a system to tackle climate change that is effective, efficient and equitable. He writes that A fair and global effort to tackle climate change needs wealthy states to take the lead in CO2 cuts:

The Bali summit on climate change, which starts next week, will seek to lay the foundations for a new global agreement on reducing the greenhouse gas emissions that cause rising temperatures and climate change. Ambitious targets for emission reduction must be at the heart of that agreement, together with effective market mechanisms that encourage emission trading between countries, rich and poor. The problem of climate change involves a fundamental failure of markets: those who damage others by emitting greenhouse gases generally do not pay. Climate change is a result of the greatest market failure the world has seen.The evidence on the seriousness of the risks from inaction is now overwhelming. We risk damage on a scale larger than the two world wars of the past century. The problem is global and the response must be collaboration on a global scale. The rich countries must lead the way in taking action. And in thinking about global action to reduce greenhouse gas emissions, we must invoke three basic criteria.

The first is effectiveness: the scale of the response must be commensurate with the challenge. This means setting a target for emission reduction that can keep the risks at acceptable levels.

The overall targets of 50% reductions in emissions by 2050 (relative to 1990) agreed at the G8 summit in Heiligendamm last June are essential if we are to have a reasonable chance of keeping temperature increases below 2C or 3C. While these targets involve strong action, they are not overambitious relative to the risk of failing to achieve them.

The second criterion is efficiency: we must keep down the costs of emission reduction, using prices or taxes wherever possible. Emission trading between countries must be a central part of the story. And helping poor countries cover their costs of emission reduction gives them an incentive to join a global deal.

Third, we should be concerned about equity. Our starting point is deeply inequitable with poor countries certain to be hit earliest and hardest by climate change. But rich countries are responsible for the bulk of past emissions: US emissions are currently more than 20 tonnes of CO2 equivalent per annum, Europe’s are 10-15 tonnes, China’s five or more tonnes, India’s around one tonne, and most of Africa much less than one.

For a 50% reduction in global emissions by 2050, the world average per capita must drop from seven tonnes to two or three. Within these global targets, even a minimal view of equity demands that the rich countries’ reductions should be at least 80% – either made directly or purchased. An 80% target for rich countries would bring equality of only the flow of current emissions – around the two to three tonnes per capita level. In fact, they will have consumed the big majority of the available space in the atmosphere.

Rich countries also need to provide funding for three more key elements of a global deal. First, there should be an international programme to combat deforestation, which contributes 15-20% of emissions. For $10bn-$15bn per year, half the deforestation could be stopped.

Second, there needs to be promotion of rapid technological advance to mitigate the effects of climate change. The development of technologies must be accelerated and methods found to promote their sharing. Carbon capture and storage for coal (CCS) is particularly urgent since coal-fired electric power is currently the dominant technology around the world, and emerging nations will be investing heavily in these technologies. For $5bn a year, it should be possible to create 30 commercial-scale coal-fired CCS stations within seven or eight years.

Finally, rich countries should honour their commitment to 0.7% of GDP in aid by 2015. This would yield increases in flows of $150bn-$200bn per year. The extra costs that developing countries face as a result of climate change are likely to be upwards of $80bn a year, and it is vital that extra resources are available. This proposed programme of action can be built if rich countries take a lead in Bali on their targets, the promotion of trading mechanisms and funding for deforestation and technology. With leadership and the right incentives, developing countries will join.

The building of the deal, and its enforcement, will come from the willing participation of countries driven by the understanding that action is vital. It will not be a wait-and-see game as in World Trade Organisation talks, where nothing is done until everything is settled.

The necessary commitments are increasingly being demonstrated by political action and elections around the world. A clear idea of where we are going as a world will make action at the individual, community and country level much easier and more coherent.

These commitments must, of course, be translated into action. There is a solution in our hands. It will not be easy to build. But the alternative is too destructive to accept. Bali is an opportunity to draw the outline of a common understanding, which will both guide action now and build towards the deal.

via Globalization and Environment

Reflections

Buzz Holling’s reflections video seminar

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Holling Seminar SRC/SU - 2007Buzz Holling, recently gave a talk at the Stockholm Resilience Centre where he reflected on his career and how he has developing ideas in science and policy.

He discussed his early work on predation, his original 1973 resilience paper, adaptive management, the adaptive cycle, and Panarchy, as well as the insights, barriers, and opportu­nities that were part of his research process.

The Centre has put the talk online as a video seminar (Windows Media Player Time: 01:05:10).

Adaptation, Ecological Economics

Climate change: What to do in Bali? Avoid rearranging the deckchairs

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Soon the international climate policy will meet under the UN’s framework convention on climate change in Bali where representative’s of the world’s nations will attempt to forge an effective international strategy to succeed the Kyoto protocol when it expires in 2012. There has been a lot of thinking in recent years on what form this agreement should take, and strong statements from the world’s scientific community that the world requires immediate reductions in CO2 emissions. The head of the IPCC, Rajendra Pachauri, said “If there’s no action before 2012, that’s too late. What we do in the next two to three years will determine our future. This is the defining moment.”

British social scientists Gwyn Prins and Steve Rayner recently wrote a commentary in Nature Time to ditch Kyoto (Oct 25 2007)

The Kyoto Protocol is a symbolically important expression of governments’ concern about climate change. But as an instrument for achieving emissions reductions, it has failed. It has produced no demonstrable reductions in emissions or even in anticipated emissions growth. And it pays no more than token attention to the needs of societies to adapt to existing climate change. The impending United Nations Climate Change Conference being held in Bali in December — to decide international policy after 2012 — needs to radically rethink climate policy.

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Influenced by three major policy initiatives of the 1980s, the Kyoto strategy is elegant but misguided. Ozone depletion, acid rain and nuclear arms control are difficult problems, but compared to climate change they are relatively simple. Ozone depletion could be prevented by controlling a small suite of artificial gases, for which technical substitutes could be found. Acid rain was mainly caused by a single activity in a single industrial sector (power generation) and nuclear arms reductions were achieved by governments agreeing to a timetable for mutually verifiable reductions in warheads. None of this applies to global warming.

In practice, Kyoto depends on the top-down creation of a global market in carbon dioxide by allowing countries to buy and sell their agreed allowances of emissions. But there is little sign of a stable global carbon price emerging in the next 5–10 years. Even if such a price were to be established, it is likely to be modest — sufficient only to stimulate efficiency gains. Without a significant increase in publicly funded research and development (R&D) for clean energy technology and changes to innovation policies, there will be considerable delay before innovation catches up with this modest price signal.

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Sometimes the best line of attack is not head-on. Indirect measures can deliver much more: these range from informational instruments, such as labelling of consumer products; market instruments, such as emissions trading; and market stimuli, such as procurement programmes for clean technologies; to a few command-and-control mechanisms, such as technology standards. The benefit of this approach is that it focuses on what governments, firms and households actually do to reduce their emissions, in contrast to the directive target setting that has characterized international discussions since the late 1980s.

Because no one can know beforehand the exact consequences of any portfolio of policy measures, with a bottom-up approach, governments would focus on navigation, on maintaining course and momentum towards the goal of fundamental technological change, rather than on compliance with precise targets for emissions reductions. The flexibility of this inelegant approach would allow early mitigation efforts to serve as policy experiments from which lessons could be learned about what works, when and where. Thus cooperation, competition and control could all be brought to bear on the problem.

Does the Kyoto bandwagon have too much political momentum? We hope not. It will take courage for a policy community that has invested much in boosting Kyoto to radically rethink climate policy and adopt a bottom-up ‘social learning’ approach. But finding a face-saving way to do so is imperative. Not least, this is because today there is strong public support for climate action; but continued policy failure ‘spun’ as a story of success could lead to public withdrawal of trust and consent for action, whatever form it takes.

Nature has a follow-up discussion on this commentary on their climate blog ClimateFeedback.

A recent issue of Nature (15 November 2007) includes a letter from German climate scientist and policy advisor John Schellnhuber in which he responds. In Kyoto: no time to rearrange deckchairs on the Titaniche writes:

Gwyn Prins and Steve Rayner … manage to be perfectly right and utterly wrong at the same time. Their criticism of the bureaucratic Kyoto Protocol is justified on many crucial points (although they don’t mention that the physical impact of the protocol on the climate system would be negligible even if it worked). The novelty of this summary of well-known deficiencies in the treaty is that the list comes from independent European scientists rather than White House mandarins. Is there anything substantially new beyond that provocation?

Yes, in the sense that Prins and Rayner boldly propagate a “bottom-up ‘social learning’ ” approach to climate policy that aspires to “put public investment in energy R&D on a wartime footing”. I agree with the importance of both elements to twenty-first century climate protection, but doubt whether there is a solid causal chain linking them. Fine-scale measures and movements towards sustainability, as well as technological and institutional innovation strategies, are needed to decarbonize our industrial metabolism and to force policy-makers to face the challenges ahead. …

Time is crucial, however. It is unlikely that a bottom-up, multi-option approach alone will be able to mobilize war-level climate-protection efforts by all the major emitters (including Russia, China and India) within the one or two decades left to avert an unmanageable planetary crisis. Without a ‘global deal’ — designed for effectiveness, efficiency and fairness and providing a framework to accommodate every nation — there will be neither sufficient pressure nor appropriate orientation towards the climate solutions we desperately need. The bottom-up and top-down approaches are complementary and must be pursued interactively.

Kyoto is simply a miserable precursor of the global regime intended to deliver genuine climate stablization — and was never expected to be more. “Ditching” it now would render all the agonies involved completely meaningless after the event, denying the entire process of policy evolution the slightest chance to succeed. So, instead of rearranging the deckchairs on the Titanic through social learning, let us ditch pusillanimity.