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Bridging the divides

Filed under: — gavin @ 2 August 2008

We often discuss the issues that arise in doing interdisciplinary work in climate science, and Liz Moyer and I have a commentary on that just out in Nature Reports Climate Change. Normally I don’t mention these kinds of pieces on the blog, but in this case the editors commissioned a nice cartoon (from Mark Roberts) illustrating our point. I liked the cartoon a lot, and so it deserves as wide an audience as possible.

A bit of context is probably useful. The three main protagonists are representative of the somewhat different foci of paleo-climatologists, climate modellers and economists. Very broadly speaking, paleo-climate science is built around the analysis of single location time series (often from holes that are drilled). Climate modellers spend a lot of time trying to see what is coming up in all its complexity, while economists tend to eschew complexity and look for insight in highly idealised situations. But in order to increase the credibility of models, they have to do well at simulating past climates and what might happen in the future is certainly informed by what has happened in the past. And in order to better understand the impacts of climate change and various proposed policies, economists will need to embrace the complexity of human-climate interactions while modellers need to better understand what aspects of climate really do make a difference. None of these things will happen if we continue to all look in different directions, and more problematically, fail to support and reward those scientists who want to bridge the divides. Sea monsters notwithstanding.

270 Responses to “Bridging the divides”

  1. 251
    Jim Galasyn says:

    Rod, recently I read about a study that tried to assess global de/reforestation rates. Iirc, the US is indeed experiencing some reforestation — but this comes with the caveat that the new ecosystem is always very much poorer in biodiversity than the original. Many of these “forests” are, in fact, tree farms comprising cheap pine monocultures.

    Worse, the assessment found undiminished deforestation rates in the tropics. This is devastating to biodiversity and may also accelerate climate change, as the cloud cover that accompanies tropical forests disappears.

  2. 252
    Rod B says:

    Jim (251), Thanks. I was talking only of the United States. And I recall there was noticeable differences in losses/gains among tree types. I understand that rain/tropical forests are a whole different ballgame.

  3. 253
    CL says:

    Rod B, 250, I don’t know a lot about the figures for US forestry, and I’m certain you are smart enough to google for anything you want to know, and don’t require me to do it for you.

    In the UK, forestry is now probably better managed than any time for centuries, but all that really has happened is that timber demand is sourced worldwide and imported from countries where forests have less protection. I know that Japan has the same practices, cherishing it’s own forests while devastating forests elsewhere. Likely USA is the same.

    As Jim Galasyn says, quality is more important than quantity. Secondary re-growth, or replanting does not replace natural virgin or primary forest, like for like. That’s one of the most striking lessons I learned in my life. I studied wildlife since childhood and spent a lot of time in the woods. About 20 years back, I had the privilege of studying a bit of ancient woodland, tiny by USA standards, just 150 acres, one of a handful of fragments left in UK as forest cover since the glaciers retreated. The density of species there is astonishing. Things I’d never seen anywhere before. It takes hundreds, even thousands, of years to establish that sort of complexity and variety.

    But that place is just a tiny island in an ocean of farmed land, which must once have been similar woodland. It’s easy to smash a complex ecosystem and put something diminished and inferior in it’s place. Rats and stinging nettles and the like. But reversing the process takes a long, long time. Fortunately, there’s many enthusiastic folk working on behalf of trees these days, so, if it were not for the threat from climate change, I’d be optimistic for the future of British trees.

    But I agree with Jim Galasyn, every year enormous areas of tropical forest are lost which is a terrible tragedy, a loss to science and posterity, in addition to the bad feedback toward global warming. That’s where effort should be directed.

  4. 254
    CL says:

    Hank, 249, “Think maybe there’s something you oughta do”

    Thing is, what to do for the best ?

    I thought this was interesting. A couple of pie charts, and what conclusions to draw from them ?

  5. 255
    Hank Roberts says:

    1) insulation
    2) solar hot water

  6. 256
    Hank Roberts says:

    To see the power of paying close attention to what’s in the news and holding the editors’ and reporters’ feet to the fire, you can’t do better these days than the Calculated Risk blog (not about climate; it’s about risk and sense and cost and benefit and reading the data for yourself instead of just believing what people say).


    I’m beginning to think this kind of thing could be a regular feature: gullible (or just lazy) reporter writes some article on some housing-bust related topic which ends up being mostly free publicity for some hustler, who is treated reverently as an “expert.” …

    “… Nor do you want to miss the officer bios. Nor do you want to fail to ask yourself why a reporter thought a buncha guys who also run outfits called “Cashout Options” and “Equity Flips” and “Bailout Help” are really just kind of objective consumer advocates …

    Reporters and editors: I’m going to keep this up until it stops. So I really suggest you make it stop. If you don’t bother to evaluate your sources before you publish, I will do it after you publish.

    —-end excerpt—-

  7. 257
    Jim Eaton says:

    There is a lot of reforestation happening in the United States, but too often it is occurring after the liquidation old growth forests.

    In Alaska, for example, the U.S. Forest Service spent nearly $36 million in 2002 preparing timber sales that generated only $1.2 million in revenue. The logging of ancient forests here simply is a subsidy to a few hundred loggers. There is little domestic demand for these trees, so most of them are shipped to Japan.

    Plus a lot of forests (especially plantations) have gone up in smoke the past few years. Many of the fires that ravaged California this summer were burning in lands that had been logged and replanted. So it will take some time until these lands again are reforested.

    “33.1% —or about 303,089,000 hectares—of United States of America is forested. Of this, 34.4% —or roughly 104,182,000 hectares—is classified as primary forest, the most biodiverse form of forest.

    “Change in Forest Cover: Between 1990 and 2000, United States of America gained an average of 364,600 hectares of forest per year. The amounts to an average annual reforestation rate of 0.12%. Between 2000 and 2005, the rate of forest change decreased by 56.9% to 0.05% per annum. In total, between 1990 and 2005, United States of America gained 1.5% of its forest cover, or around 4,441,000 hectares. United States of America lost -1,086,000 hectares of its primary forest cover during that time. Deforestation rates of primary cover have decreased 1.0% since the close of the 1990s. Measuring the total rate of habitat conversion (defined as change in forest area plus change in woodland area minus net plantation expansion) for the 1990-2005 interval, United States of America lost 0.8% of its forest and woodland habitat.”

  8. 258
    Rod B says:

    CL (253) and Jim (257), thanks; very informative.

  9. 259
    CL says:

    “…the second largest continuous area of forest in the world: the Central African Rainforest. This great block of green canopy contains some of the richest plant and animal habitat in existence. This area of forest also contains, potentially, around 37 billion tonnes of carbon, more than the whole of Southeast Asia and the USA combined; that is over five times as much carbon as all human activity on Earth produces each year.

    The extent of this vital carbon “sink” is shrinking each year. In 1990 the Central African Rainforest occupied 2.5 million square kilometres; in 2005 it occupied less than 2.4 million km², a reduction of about five percent in total area. Five percent may not seem like a lot, but when you look at the speed the forest is degrading at the same time then you realise something fundamental is happening. According to a report published in 2007, over a quarter of this unique habitat had been earmarked for logging, while only twelve percent was officially protected – in practice not protected at all.”

    From this online book :

  10. 260
    CL says:

    From the same source,
    (Part one,chap.6)

    “..the Central African Rainforest was under extreme pressure from logging and other practices including the mining of mineral resources. The natural Canadian Boreal forest may not have the deeply rich ecological diversity of the rainforest, but neither is it a monoculture plantation of identical trees marching across the landscape in some grotesque military spectacle. The “owners” of plantations in these forests proudly claim the planting of two trees for every one removed – look at the back of a birthday card, or a pad of paper – and they are not lying; yet they fail to explain that those two trees are part of a cash crop, substituting a complex interweaving of dependent species for a desert of quick growing sawmill fodder.

    The Canadian Government report to the UN Food and Agricultural Organisation every five years on the state of its forests, yet miraculously have stated identical figures in each of the previous three reports: an outstandingly precise 310,134 hectares. This has been eagerly seized upon by the Forest Products Association of Canada who state: “If all countries of the world could eliminate or virtually eliminate deforestation as Canada has done, this would have an impact comparable to eliminating fossil fuel emissions in the United States in terms of advancing GHG mitigation efforts”, which would be wonderful if it were true. The FAO, in fact, refer to “the absence of information about forest plantations in Canada”and go on to state:

    Wood removals are declining in Mexico and the United States of America, while they continue to increase in Canada. This trend is reflected in economic data, with modest growth in several economic indicators in Canada and a slight decline in the other two.

    Something else in the FAO report caught my eye, too. It is in a section called “Forest Health and Vitality”. British Columbia, it seems, is undergoing its own logging frenzy, not for economic gain, but to protect against potential economic loss. “The Government of British Columbia has dramatically increased logging in an attempt to slow the spread of the beetle by removing recently infested trees and to recover value from trees already killed.” If BC is indeed logging to protect its future, then somewhere else trees are having to be planted at a rate sufficient to keep up with this; which means that the age and diversity of the Boreal is taking a direct hit, and the Canadian Government are making bare-faced lies about the state of this mighty ecosystem.”

  11. 261
    Nick Gotts says:

    Timothy Chase@175,

    I’ve been away, so just a few quick points to take up your comments and queries:
    1) As an “Austrian”, I think you’re almost as far from the neoclassical mainstream as I am!
    2) Economics is more liable than the physical sciences to ideological pressures, because its conclusions are used to justify existing distributions of wealth. Of course saying this is not a refutation of neoclassical microeconomics – that depends on its wildly inaccurate picture of human decision-making, its fixation on equilibrium phenomena, and its cornucopian assumptions about natural resources. On at least the first two of these, I would think as an “Austrian” you agree with me, at least in the negative sense of criticising the current majority position – and you say above that markets aren’t particularly good at dealing with environmental problems. Incidentally, I agree Adam Smith is a good place to start – but so did Marx.
    3) The approach I advocate is democratic socia-lism, with decision-making organised using an approach called negotiated coordination. I’ve mentioned the latter before, the best current reference is probably “Democracy and Economic Planning: The Political Economy of a Self-Governing Society” Pat Devine, Polity Press, Cambridge UK and Westview Press. Boulder, CO., USA, 1988. Pat’s a friend of mine, who I believe is working on an update.

    Theoretically, I’d describe myself as a world-systems theorist at the macro-scale (capitalism can only be understood as an inter-societal system in which elites in “core” states use state power to maintain their position both internally and externally) and a radical institutionalist at the meso-scale (institutional systems – where an institution is a coordinated set of norms – are constitutive of individual motivational structures). I regard the attempt to separate out an “economic sphere” which can be studied independently of broader socio-techno-ecosystems as fundamentally misconceived. I realise the above would need a lot of unpacking to stand alone, but you did ask. Google William Dugger for a starting point on radical institutionalism, Christopher Chase-Dunn for my favourite world-systems theorist. Others who’ve influenced me a lot include Herbert Simon (also a Nobel-winning economist), and the school of experimental and cross-cultural economists around Samuel Bowles. Finally, I have a recent article in “Ecology and Society” ( could be of some interest.

    On other points, I agree with much of what CL and Jess have said.

  12. 262
    Nick Gotts says:

    Timothy Chase,
    Incidentally, I’m not sufficiently familiar with the minimum wage example you gave to know whether Sowell is right in that case, but there clearly are cases (like the recent UK one) where the predicted drop in employment has not occurred. Changing one specific aspect of a complex system won’t always have the same effect: it depends on what else is going on.

  13. 263
    CL says:

    Gazeing wistfully at the little cartoon map at the head of this topic…where are the forests ? Where are the rivers ?

    “it is obvious that economic growth is ultimately unsustainable – especially given the narrow, capital based definition used to define the term “economy” in the industrial world – yet, we continue to be fobbed off by the message that we must have economic growth in order to progress or develop as humans. Of course, if we judge development or progress in terms of the number of televisions, computers and cars we have, the size of home we have or the amount of energy we use; then economic growth most certainly does lead to a more “developed” human race. If we judge development or progress on rather more esoteric (and, quite frankly, more important) measures such as clean water and air, physical and mental health, freedom of expression, and having a future that our descendants will be able to thrive in; then economic growth is failing on almost all of these counts. Humans in every place touched by the rank hand of industrialisation are told that development based upon economic growth, is good. When you think about it, though, the only true form of development is that which moves us into balance with our natural environment – in effect a reversal of what we are now doing. You do not have to be financially prosperous in order for your water to be clean – you just need a basic level of hygiene, sensible water management techniques and, most of all, a lack of toxic muck being poured into the water supply by industrial processes.
    Economic growth as a necessity is the biggest lie that humanity has ever been sold; yet we are lapping it up because the lie is repeated day after day by every information source we are unfortunate enough to be subjected to.”


    “The delta of the great Colorado River – where once it swept into the Gulf of California – used to be the most wonder-filled wetland in the whole North American continent.
    Some 400 species of plants and animals – including jaguars, beaver and the world’s smallest dolphin- thronged its 3,000 square miles of wetlands, lagoons and tidal pools. The local people made a good living fishing its teeming waters. Now it has become a forbidding desert of salt flats and giant heaps of dead clamshells. The fishing boats have been long since beached; the destitute people have to seek what work they can in wheat fields and tortilla factories far away.”


    “The world’s great rivers are drying up at an alarming rate, with devastating consequences for humanity, animals and the future of the planet.”


    “In tropical areas, hydropower reservoirs may be much worse climate polluters than even coal power plants”


  14. 264
    Rod B says:

    Nick (261), you said, “…[deficiencies] of neoclassical microeconomics – that depends on its wildly inaccurate picture of human decision-making, its fixation on equilibrium phenomena, and its cornucopian assumptions about natural resources….”

    IMO that cleanly and succinctly describes the deficiencies of economic models and of economists viz-a-viz AGW — or for that matter viz-a-viz anything — better than I have seen. Thanks.

    Unfortunately, just so my accolade doesn’t inappropriately spill over, I have to assert for the record that I do not agree with your further analysis and conclusions regarding democratic soc_ial_ism.

  15. 265
    Mark says:

    Nick, 262, you MUST be wrong!!!! The economics graph says so!!!

    Sigh. It seems as though denialism is all around sometimes, doesn’t it.

  16. 266
    Kevin Leahy says:

    It is a bit of an over generalization to suggest economists are in some sort of opposition to the idea of climate change — many are involved, working on “how do we resolve this issue” as opposed to working to refine the science, which isn’t thier job.

    Check out:


  17. 267
    Mark R says:

    There are three main problems facing humanity, as I see it. First, there is the sheer number of human beings presently alive on the planet. Therefore, it doesn’t much matter what one individual does or does not do, it matters what 6.7 billion humans do. What we do, collectively, is chew upon every other form of life in sight, which brings up the second point: severe degradation of all life ecosystems on the planet. The third matter, of course, is rapid and severe climate change, which exacerbates the first two effects. If the first two problems weren’t bad enough (and they clearly are), then global warming is the accelerant added to the fire.
    Picayune arguments as to whether or not changing one’s light bulbs or driving a hybrid auto are a moral good and will allow us to collectively survive are rendered nonsensical by the scope of the matter. In all other cases of human history and likely pre-history, when faced with a population overextended beyond its resources, human populations collapse back to a sustainable level, just as with all other animals and other creatures. We cannot escape the laws of life on this planet, and until we learn to eat sand, that will remain the truth.
    Economists view life with blinders on. They are only concerned with the movement and exchange of money, with lame and amorphous justifications for it like “self-interest.” Economics is useful as far as it goes, as a social tool, but it is not very useful for life as a whole (i.e., ALL of life). Furthermore, economics is always, always interpreted from the human standpoint, not in essential broader terms. We do not exist, as a species, in a bio-vacuum.
    In David Montgomery’s recent book on soil, Dirt, he presents an overview of human agricultural exploitation of the critical, thin layer of humus upon which our very lives–and the existence of nearly all terrestrial life, depends. We have thoughtlessly and selfishly destroyed every rich, life-preserving soil on this planet, and there is no room for further ignorant and maniacal exploitation. This fact alone will diminish our numbers before long–and permanently. Add to this the destruction of life systems in the ocean, and the emptying of the skies of avian fauna, and we are faced with living (or not) upon a desertified, deserted world which has been seriously crippled for rest of our unimportant existence as a species.
    There is no “energy solution” which can forestall the steepest decline in human numbers in our collective experience (ever?), meaning billions of people must and necessarily will die off shortly. Yes, every drop of practical oil will continue to be burnt, and every lump of coal will also go up some chimney, as long as we are able. Meanwhile, the entire planet which is Rome continues to burn, and we are unable to stop ourselves from our own self-destructive will to survive at any cost. The cost will be great.

  18. 268
    Ray Ladbury says:

    Mark R., While I see great challenges ahead, I think that there is as much danger in the complacency of hopelessness as there is in the complacency of denial. We can certainly buy time to find solutions by driving hybrids and changing lightbulbs–even building clotheslines. The people of Juneau, AK managed to cut back energy consumption by 30% with relative ease whan avalanches cut them off from hydroelectic power earlier this year.
    Humans face not 3 major problems, but really just one: sustainability–that is maintaining progress in a way that is consistent with and conducive to the health of our finite environment. Even if we could stabilize human population tomorrow, there would still be pressure to increase consumption as the poor strive to survive and perhaps prosper and the wealthy strive to become wealthier. Even if we were to decrease human population we would be faced with the threats of deflation and caring for an aging population that always result when human population declines. Peak oil complicates things. Development complicates things further, and climate change makes things difficult indeed. I do, however, think that it is just possible that human civilization can survive and prosper if we can navigate between the Scylla of denial and the Charbidis of hopelessness.

  19. 269
    CL says:

    Here is some action that can be taken

    If anyone is interested, there’s just been a change in the planning rules in Pembrokeshire, Wales , UK, where I live, just a few weeks ago, so there’s new opportunities opening up here to allow that kind of dwelling.

    I have 25 acres, and cottage, where I’ve been for 20 years, and which is more than I can cope with because of health and getting old, so shareing with someone would probably be a mutually beneficial arrangement. I have the timber already, highest quality oak that’s been cut 20 years.

    Main problem, as far as I can judge, would be individual personal compatibility. As some here may acknowledge, I’m prone to have opinions :-)

    If anyone feel inspired to explore possibilities, I can be contacted at wolf dot bird at virgin dot net.

    Here’s other examples

  20. 270
    neil pelkey says:

    Dear Jeff Davis, You are correct that none of us has really good handle on carbon based energy supplies. The nuttiness is the simultaneous belief that we are past peak carbon and CO2 based global warming will stay a problem. If we truly are past peak carbon, we will see 200-300$ a barrel oil and massive reductions in it use. Just like we saw with 140 per barrel.

    I do look forward to the nuttiness that it as a random clumping of La Ninas + snow reflection feedback effects that is causing the the global temperature flattening, but it was NOT a cluster of el Nino’s and snow/ice feedback effects that caused the upsurge in warming.

    The nuttiness is that when the fever pitch of battle is such that we stop thinking.

    The the certain people who want oil company executives tried for crimes against humanity. Maybe having them tried for collusion, fraud, violation of federal contracts, influence peddling, bribery, and/or racketeering would be a better first option. Especially since they may actually be guilty of some of those crimes and misdemeanors. When the main people who could be instrumental in pushing for such rational approaches start sounding a little deranged (and in some cases more than a little deranged) hope is lost as few prosecutors want to go to court with a unreliable witness.