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More from Shellenberger and Nordhaus on uncoupling energy policy from climate policy

Monday, March 29th, 2010

Their latest piece: Freeing energy policy from the climate change debate.


Environmental advocates — with help from pollsters, psychologists, and cognitive scientists — have long understood that global warming represented a particularly problematic threat around which to mobilize public opinion. The threat is distant, abstract, and difficult to visualize. Faced with a public that has seemed largely indifferent to the possibility of severe climactic disruptions resulting from global warming, some environmentalists have tried to characterize the threat as more immediate, mostly by suggesting that global warming was already adversely impacting human societies, primarily in the form of increasingly deadly natural disasters.

The result has been an ever-escalating set of demands on climate science, with greens and their allies often attempting to represent climate science as apocalyptic, imminent, and certain, in no small part so that they could characterize all resistance as corrupt, anti-scientific, short-sighted, or ignorant. Greens pushed climate scientists to become outspoken advocates of action to address global warming. Captivated by the notion that their voices and expertise were singularly necessary to save the world, some climate scientists attempted to oblige. The result is that the use, and misuse, of climate science by advocates began to wash back into the science itself.

Not everyone agrees with this assessment, as suggested recently by sociologist Bill Freudenburg and others that climate science errs in being too conservative rather than too apocalyptic.

Nevertheless, S & N want us to consider the extent to which dramatic energy policy can be rolled out in the absence of incentives like carbon taxes or cap and trade if, as they suggest, we are wasting time using science to pursue the latter:

In the end, there is no avoiding the enormous uncertainties inherent to our understanding of climate change. Whether 350 parts per million of CO2 in the atmosphere, or 450 or 550, is the right number in terms of atmospheric stabilization, any prudent strategy to minimize future risks associated with catastrophic climate change involves decarbonizing our economy as rapidly as possible. Stronger evidence of climate change from scientists was never going to drive Americans to demand economically painful limits on carbon emissions or energy use. And uncertainty about climate science will not deter Americans from embracing energy and other policies that they perceive to be in the nation’s economic, national security, and environmental interest. This was the case in 1988 and is still largely the case today.

Now is the time to free energy policy from climate science. In recent years, bipartisan agreement has grown on the need to decarbonize our energy supply through the expansion of renewables, nuclear power, and natural gas, as well as increased funding of research and development of new energy technologies. Carbon caps may remain as aspirational targets, but the primary role for carbon pricing, whether through auctioning pollution permits or a carbon tax, should be to fund low-carbon energy research, development, and deployment.


Photo Credit: / CC BY-ND 2.0

Posted in communication and framing, energy, solutions | No Comments »

This week’s good ideas in campus sustainability: 3/29/10

Monday, March 29th, 2010

AASHE is showcasing the new American College & University Presidents’ Climate Commitment (ACUPCC) 2009 report, which highlights climate leadership in higher education.

The Report includes highlights from 2009; a list of innovative ways schools are applying their Climate Action Plans to areas such as curriculum, transportation, renewable energy, and partnerships within and outside the campus gates; a description of the impact the Commitment has had on the reduction of carbon emissions; information on the Climate Action Plans that have been submitted; a list of resources available to signatory institutions; and the ACUPCC budget. The ACUPCC, launched in early 2007, is currently comprised of 677 schools in all 50 states and the District of Columbia – representing nearly six million students and about one third of the US higher education student population.

Link to story

Link to the ACUPCC report (pdf)


More information:  AASHE bulletin 3/29/10

Posted in campus sustainability, higher education, solutions, sustainability | No Comments »

Global carbon cycle sees increase in soil carbon loss

Thursday, March 25th, 2010

A lot of us are on the lookout for increased releases of soil carbon in northern ecosystems, which could signal the initiation of a positive feedback to warming.   Remember that more warming has the possibility of increasing decomposition of soil carbon, which causes the release of more CO2 to the atmosphere, causing further warming (the feedback mechanism).

I was delighted to open today’s issue of Nature and see an article by one of my colleagues—Ben Bond-Lamberty (together with colleague Allison Thomson)—who completed a global assessment of soil carbon release.1

To give you a bit of a primer, a couple of decades ago, we used to think that soils worldwide released about 60 gigatons of carbon each year.   That’s about six times the total current release of anthropogenic carbon from fossil fuels and deforestation combined.  So no small potatoes.   You can therefore think of humans as “decomposers” who release about 1/6 the amount of carbon that soil microbes do each year.

Based on a meta-analysis of 439 studies of soil carbon respiration, Ben and Allison discovered that this number has risen to about 98 gigatons (+/- 12 Gt) per year in 2008 and that it’s growing by about 0.1 gigaton per year.  Part of this is due to better estimates of global soil respiration, but as their data suggest, part of it is also a genuine upward trend.

The trend of increasing soil CO2 release over time correlates with the late-20th-century rise in air temperatures.

Case closed on the positive feedback?  Not so fast they wisely warn us.  At face value, this change is consistent with temperature-driven increases in soil respiration.  However, Ben and Allison are right to point out that we need to be a bit careful and ask where that extra carbon is coming from.  For simplicity, we can think of two sources:

  • As the positive feedback hypothesis suggests, it might be old soil carbon that is decomposing now that microbes are warmer and more active.
  • However, a world with more CO2 will also fertilize tree growth and lead to increased production of things like leaves, branches, and tree stems that fall to the ground each year.  If climate change is causing more of this “litterfall” to happen, then the increased decomposition Ben and Allison detected might simply reflect that fact there is more dead fresh litter falling onto soils around the globe.

Either possibility is interesting, but it’s really the first one that’s worrisome in terms of accelerated climate warming.  Why?  Because a jazzed-up carbon cycle (bullet #2) doesn’t really add any new carbon to the atmosphere.  If trees grow more and then that growth is released as greater soil decomposition, all we have done is made the plant uptake arrow bigger and the soil release arrow bigger.  No net change in atmospheric CO2.

It’s hard to tell at this point if one or the other (or both) mechanisms are at play.  If it is the beginning of a climate warming positive feedback, it’s all the more imperative that we  get carbon emissions and temperatures under control quickly.

1Bond-Lamberty, B., & Thomson, A. (2010). Temperature-associated increases in the global soil respiration record Nature, 464 (7288), 579-582 DOI: 10.1038/nature08930


Photo Credit: One of my photos of a low-Arctic Sphagnum peat bog in Manitoba, Canada, which you can view at my Flickr site.

Posted in climate change science | No Comments »

Food aid and long-term food security

Sunday, March 21st, 2010

As we saw in a previous post, food aid is a complex issue.   On one hand, it’s critical for acute crisis situations where people are starving because of things like war and natural disasters.  On the other hand, in more chronic situations of malnutrition, food aid and cheap imports have the capacity to undermine local food production, which, in the long run, harms the prospect of people feeding themselves through local production.

A farmer’s worst enemy is free food and cheap imports.

In recent years, we have seen this play out in Africa, as Oxfam acknowledges.  MSNBC is running a story today, “With cheap food imports, Haiti can’t feed itself,” about how the same thing has happened there.  Worth reading.

There is also a larger debate at play here about the implications of free trade and industrialized food production.


Photo credit: / CC BY-NC-ND 2.0

Posted in food and agriculture, race and class, solutions | 2 Comments »

New analysis of pesticides and bee colony collapse disorder

Friday, March 19th, 2010

European bee populations are on the decline worldwide.   Who cares?  These bees are major pollinators of crops and therefore perform, for free, a vital ecological service worth about $U.S. 14 billion per year.  Not to mention the many other species of non-crop flowering plants that reproduce with the help of insects like this.

The recent kind of decline is specific—only female worker bees disappear—and has been given the name colony collapse disorder (CCD).  Nobody has figured out why this is happening.  The potential list of culprits includes mites, viruses, synthetic chemicals, and other factors.

In an article this week in PLoS ONE, Christopher Mullin and colleagues explore further the potential link between pesticides and CCD.1


One third of honey bee colonies in the US were lost during each of the last three winters between ’06-’09. This alarming overwinter along with other losses of this primary pollinator, Apis mellifera L., as well as those of native pollinators, has been documented in North America and Europe. The most recent manifestation of this decline, Colony Collapse Disorder (CCD), has led to a significant collaborative effort involving several land grant universities, Departments of Agriculture and the USDA.

We have found 121 different pesticides and metabolites within 887 wax, pollen, bee and associated hive samples. Almost 60% of the 259 wax and 350 pollen samples contained at least one systemic pesticide, and over 47% had both in-hive acaricides fluvalinate and coumaphos, and chlorothalonil, a widely-used fungicide. In bee pollen were found chlorothalonil at levels up to 99 ppm and the insecticides aldicarb, carbaryl, chlorpyrifos and imidacloprid, fungicides boscalid, captan and myclobutanil, and herbicide pendimethalin at 1 ppm levels. Almost all comb and foundation wax samples (98%) were contaminated with up to 204 and 94 ppm, respectively, of fluvalinate and coumaphos, and lower amounts of amitraz degradates and chlorothalonil, with an average of 6 pesticide detections per sample and a high of 39. There were fewer pesticides found in adults and brood except for those linked with bee kills by permethrin (20 ppm) and fipronil (3.1 ppm).

The 98 pesticides and metabolites detected in mixtures up to 214 ppm in bee pollen alone represents a remarkably high level for toxicants in the brood and adult food of this primary pollinator. This represents over half of the maximum individual pesticide incidences ever reported for apiaries. While exposure to many of these neurotoxicants elicits acute and sublethal reductions in honey bee fitness, the effects of these materials in combinations and their direct association with CCD or declining bee health remains to be determined.

The high frequency of multiple pesticides in bee collected pollen and wax indicates that pesticide interactions need thorough investigation before their roles in decreasing bee health can be either supported or refuted. The large number of studies to date, are limited by being done on mostly one compound at a time, as well as using whole colonies where the timing of contaminated pollen intake and its utilization by the colony are difficult to interpret as a causal relationship. Laboratory studies have clearly indicated sublethal impacts on honey bee learning, immune system functioning, and synergism of insecticide toxicity by fungicides, yet combinations of herbicides with fungicides and insecticides in 3 or more component mixtures have not been studied.

The widespread occurrence of multiple residues, some at toxic levels for single compounds, and the lack of any scientific literature on the biological consequences of combinations of pesticides, argues strongly for urgent changes in regulatory policies regarding pesticide registration and monitoring procedures as they relate to pollinator safety. This further calls for emergency funding to address the myriad holes in our scientific understanding of pesticide consequences for pollinators. The relegation of bee toxicity for registered compounds to impact only label warnings, and the underestimation of systemic pesticide hazards to bees in the registration process may well have contributed to widespread pesticide contamination of pollen, the primary food source of our major pollinator. Is risking the $14 billion contribution of pollinators to our food system really worth lack of action?

1Christopher A. Mullin, Maryann Frazier, James L. Frazier, Sara Ashcraft, Roger Simonds, Dennis vanEngelsdorp, Jeffery S. Pettis (2010). High Levels of Miticides and Agrochemicals in North American Apiaries: Implications for Honey Bee Health PLoS ONE


Photo Credit: / CC BY-NC-ND 2.0

Posted in biodiversity science, food and agriculture, organic, pollutants, toxics | 2 Comments »

A message about communicating climate science

Thursday, March 18th, 2010

Matt Nisbet has an interesting piece, Chill Out: Climate scientists are getting a little too angry for their own good, at Slate today that adds another view to the ongoing discussion about environmental literacy and communication.

Posted in behavior, climate change science, communication and framing | No Comments »

Stavins: “What’s the Proper Role of Individuals and Institutions in Addressing Climate Change?”

Saturday, March 13th, 2010

That’s the question asked by Robert Stavins at Harvard.  This piece is worth reading.  He wrestles with many of the same questions that many of us in higher education have thought a lot about (here, here, here, and here):

My view of a university’s responsibilities in the environmental realm is similar.  Our direct impact on the natural environment — such as in terms of CO2 emissions from our heating plants — is absolutely trivial compared with the impacts on the environment (including climate change) of our products:  knowledge produced through research, informed students produced through our teaching, and outreach to the policy world carried out by faculty.

So, I suggested to the students that if they were really concerned with how the university affects climate change, then their greatest attention should be given to priorities and performance in the realms of teaching, research, and outreach.

Of course, it is also true that work on the “greening of the university” can in some cases play a relevant role in research and teaching.  And, more broadly — and more importantly — the university’s actions in regard to its “carbon footprint” can have symbolic value.  And symbolic actions — even when they mean little in terms of real, direct impacts — can have effects in the larger political world.  This is particularly true in the case of a prominent university, such as my own.

But, overall, my institution’s greatest opportunity — indeed, its greatest responsibility — with regard to addressing global climate change is and will be through its research, teaching, and outreach to the policy community.

Although I applaud the call for more emphasis on environmental teaching and the addition of environmental courses, several impediments exist in higher education and beyond which make it difficult to translate these actions into a more environmentally literate society:

  • Disciplines, departments, and majors have long been divided into separate silos.  We reward specialization and expertise over the kinds of interdisciplinarity that is needed to conceive of and deal with global change problems.  As we have seen in previous posts, it’s time for higher education to consider adding problem-centered approaches to the general curriculum.
  • As a result, training students about the environment is often the responsibility of environmental studies and science (ESS) programs.   This is a problem because it absolves most departments and faculty from having to engage the environment as a serious issue.  Many programs at a typical university operate as if humans have little or no connection to the natural world.  Until human systems are properly embedded in natural systems and students are encouraged/required to explore these linkages, there is little reason for students to associate the human experience with impacts on the natural world.
  • These kinds of structures are problematic.   At best, it means that most students in higher education receive little substantive training in how their lives connect with the natural world.  At worst, students are trained to perpetuate disciplinary tradition that (1) ignores the relationship between human societies and the environment and (2) values high achievement in a world that is ecologically unsustainable and socially unjust as a measure of success.
  • There can be limits to a “more knowledge” approach.  Namely, as we have seen with climate communication, cultural values shape the perception/reception of information.  Just as  scientific facts seldom speak for themselves, we can’t expect a push for more education to always solve environmental challenges either.  The way messages are framed is important.  And the cultural context of the target audience is also critical.  Most people in the world have a very different cultural background than Harvard undergraduates.

Posted in behavior, communication and framing, higher education, nature and culture, sustainability | No Comments »

High Arctic soil carbon underestimated

Saturday, March 13th, 2010

Most people have heard about the potential positive feedback of soil carbon on climate: As temperatures warm, soil microbes are more active and permafrost begins to thaw–both of which can hasten decomposition and the release of CO2 to the atmosphere.  This, in turn, has the potential to accelerate warming.

A lot of us who study climate warming impacts in boreal and Arctic ecosystems are interested in this problem.  There are a few things we keep an eye on:

  • How fast are temperatures warming in the Arctic?
  • How fast is permafrost thawing?
  • How much soil carbon is there?

All of these questions are active areas of research.  Increase any of them, and you have the possibility of strengthening the positive feedback.  The third one is particularly interesting.   The more we study and inventory soil carbon at high latitudes, the more we revise upwards the estimate of soil carbon.

Here’s an example:  The atmosphere contains about 750 gigatons of carbon.  When I was in grad school back in the early 90′s, we thought that boreal and arctic soils might have stored around 350 gigatons—about half the atmospheric content.   With the discovery of extremely carbon-rich yedoma soils in Siberia, we learned that this number might be a serious underestimate.   And as we learn more about soil carbon stored in deeper, harder-to-sample permafrost soils, we are coming to the realization that high-latitude soils may store between 1000-1700 gigatons—substantially more than the atmosphere (here’s one example).

Let’s say for illustration that the real number is 1500 gigatons.  This means that warming would only need to cause a loss of 1/2 of 1% of this soil carbon to release 7.5 gigatons—roughly the total amount of fossil fuel carbon released worldwide each year.   Thus, small changes in decomposition of a huge soil carbon pool can lead to carbon releases that rival anthropogenic emissions.

In a forthcoming issue of Global Biogeochemical Cycles,1 Jennifer Howarth Burnham and Ronald Sletten further illustrate that the more we sample, the more this soil carbon number goes up.

Focusing on Greenland, they dug 55 soil pits and measured soil carbon.  Then, they extrapolated these estimates to the rest of the circum high Arctic by (1) linking soil carbon to certain vegetation types and (2) using satellite imagery estimates of the area of each vegetation type to estimate soil carbon for a much larger region.

Although the new number they produced is not large (12 gigatons), it is five times the previous estimate for High Arctic soils.   It’s important to note that much of the High Arctic is a polar desert with little plant growth that could contribute to soil carbon, so it’s not surprising that more of the soil carbon is farther south—in boreal and subarctic regions.

One important caveat is that they only sampled surface soils that thaw during summer and are easy to sample.  By omitting deeper permafrost soils, they probably underestimated the total.

And so we keep sampling…

1Burnham, J. H., and R. S. Sletten (2010). Spatial Distribution of Soil Organic Carbon in Northwest Greenland and Underestimates of High Arctic Carbon Stores Global Biogeochemical Cycles : 10.1029/2009GB003660


Photo credit:  One of my photos from the Canadian Arctic that you can view on my flickr site

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Posted in climate change science, polar ice | No Comments »

More on natural variability vs. anthropogenic warming

Thursday, March 11th, 2010

Matthew McDermot features another GRL article that comes to a similar conclusion as the last post:  The kinds of natural variability we have experienced in volcanoes and solar cycles over the past 1000 years has been relatively small compared to the temperature changes we face with anthropogenic greenhouse gases.

This paper by Thomas Crowley is an earlier example of how climate scientists compare the relative effects of natural vs. human factors on climate over the past 1000 years.

Posted in climate change science | 1 Comment »

Natural climate factors unlikely to put the brakes on greenhouse-gas-driven sea level rise this century

Wednesday, March 10th, 2010

The IPCC 2007 report projected a conservative sea level rise of about 18-59 cm by the year 2100.

Why conservative?  Because it mainly accounted for things we know are happening and can measure well—like thermal expansion of the ocean and melting of land glaciers (see here for a discussion of the Kilimanjaro example).  What it doesn’t do so well is account for all of the potential ways that the big ice sheets (Greenland and Antarctica) can contribute to sea level rise.  Things like ice flow and mass loss are generally assumed to be constant, even though recent research papers discussed in previous posts (here and here) suggest they are accelerating.

Since the publication of the IPCC report in 2007, there have been several studies suggesting that sea level rise will be 1-2 meters or more by 2100 (one example here).  One study looked at geological evidence for sea level rise during the previous interglacial period 125,000 years ago, which was 1-2 degrees C warmer than today.  Their work indicated that there was a 95% chance that sea level rose by 6 meters (22 feet).

In a forthcoming issue of Geophysical Research Letters,  Svetlana Jevrejeva and colleagues used statistical models to project sea level rise by 2100.1 But they also did something else interesting.  They looked back several thousands of years to the most extreme events that could cause climate cooling—things like severe volcanic eruptions, which create stratospheric dust clouds that block sunlight.

If events like this were to happen again, they asked, would they cause enough cooling to be able to slow sea level rise caused by greenhouse gases?

The answer is no.  There appears to be no natural factors like vulcanism that will significantly slow greenhouse-gas-driven sea level rise that we are already committed to or future sea level rise that we may experience if we continue to emit fossil fuels.

Excerpts (emphasis mine):

  • With the assumption that sea level will continue to respond over the next 100 years to the same forcings that have influenced it during the past 1000 years, we estimate 0.6 -1.6 m of global sea level rise in the 21st century using a statistical model driven by projected natural and anthropogenic forcings.
  • In contrast to the 20th century sea level rise that was associated with a significant contribution of 25% from natural (solar and volcanic) forcing, 21st century sea level rise will be clearly dominated by the changes in CO2 and other greenhouse gases.
  • Alternative scenarios for solar forcing with a potential decrease in solar irradiance of 1W/m2 (using the lowest level recorded throughout the last 9300 years) only produce a 10-20 cm reduction in our estimate of 21st century sea level rise.
  • If we utilize the 13th century past volcanic forcing to estimate a possible (but unlikely) contribution from volcanic activity, then an almost negligible 8 cm decrease is projected in the estimated sea level rise.
  • The suggested reduction of radiative forcing by injections of SO2 into atmosphere (equivalent to a Pinatubo eruption every 4 years) would be equivalent to delaying sea level rise by 12 -20 years.
  • A “no changes in radiative forcing” scenario produced 16-22 cm (with lower limit of 10 cm and upper limit of 31 cm) sea level rise in the 21 century due to the inertia of the climate system, providing evidence that conditions established during the past centuries have already committed us to a considerable global sea level rise during the next 100 years.

1Jevrejeva, S., J. C. Moore, and A. Grinsted (2010). How will sea level respond to changes in natural and anthropogenic forcings by 2100? Geophysical Research Letters : 10.1029/2010GL042947

UPDATE:  RealClimate provides more explanation of the IPCC being too cautious about sea level rise.


Photo Credit: / CC BY 2.0

Posted in climate adaptation, climate change science, polar ice, sea level rise | No Comments »

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