New WMO Greenhouse Gas Bulletin

The WMO’s annual report on the the status of atmospheric greenhouse gases was released today.  As usual, the report provides some excellent resources for teaching climate courses, including figures including the latest assessments of greenhouse gas trends and case studies suitable for use in climate and energy courses. Among the report’s key findings:

  • Atmospheric concentrations of carbon dioxide, responsible for 66% of radiative forcing of long-lived greenhouse gases (LLGHGs), reached 405.5ppm at the end of 2017, up 2.2 ppm from 2016. While this rate of increase was smaller than between 2015-2016, are equal to the average growth rate over the past decade. Atmospheric levels of carbon dioxide are now 146% of pre-industrial levels;
  • Atmospheric concentrations of methane, responsible for 17% of radiative forcing of LLGHGs, reached 722 ppb at the end of 2017, up 7 ppb from 2016.  Atmospheric levels of methane are now 257% of pre-industrial levels;
  • Atmospheric concentrations of nitrous oxide, responsible for 6% of radiative forcing of LLGHGs, reached 329.9 ppb at the end of 2017, up 0.9 ppb from 2016.  Atmospheric levels of methane are now 122% of pre-industrial levels;
  • Stratospheric chlorofluorocarbons and other minor halogenated gases are responsible for approximately 11% of radiative forcing of LLGHGs. While most CFCs and halons are in decline, some hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) with very high global warming potential are increasing. Moreover, there’s concern about recent unexpected increases in CFC-11 emissions, most likely attributable to increased production in eastern Asia. Thus, despite continued regulation under the Montreal Protocol, the rate of decline of this potent greenhouse gas has slowed to two-thirds of what it was the previous century;
  • Among the most interesting findings in the report’s case studies:
    •  New Zealand’s land-use, land-use change and forestry offset about 30% of its anthropogenic greenhouse gas emissions;
    • In Canada, where the oil and gas sector accounts for roughly half of total methanes emissions in the national inventory, a recent study indicates that methane emissions in some operations may be 25-50% higher

As for other materials, you can find them below:

1. The Future of Education: Tech Trends Reshaping the Learning Landscape


The Royal Society’s New Report on Greenhouse Gas Removal

In 2009, the UK’s Royal Society published one of the seminal studies on the emerging field of climate geoengineering, Geoengineering the Climate. This week, it released a successor report, focused on one of the recognized sub-categories of geoengineering, “greenhouse gas removal,”(GGR) also often referred to as “carbon dioxide removal” or negative emissions technologies (NETs).

The UK’s Royal Society has just released a report on “greenhouse gas removal” (GGR)—a diverse set of technologies and practices for removing greenhouse gases, like carbon dioxide, from the atmosphere and sequestering them. GGR is also sometimes called “carbon dioxide removal” or “negative emissions.” This report, written in conjunction with the Royal Academy of Engineering, comes nearly a decade after the Royal Society’s seminal 2009 report on climate engineering, Geoengineering the Climate, which considered both GGR and solar geoengineering methods.

In this post, I will attempt to summarize the key conclusions of the report, and then briefly discuss a number of outstanding issues that should be addressed in future analyses of GGR options.


  1. Overview
  • The large-scale deployment of GGR options will likely prove to be critical in meeting the Paris Agreement’s objective of reaching net-zero emissions as well as its temperature objectives: holding temperatures to 2°C above pre-industrial levels will likely require removing several hundred gigatons of carbon dioxide, and holding temperatures to 5°C would take “close to a thousand” gigatons
  • While the initial focus in terms of potential deployment of GGR approaches was on forests and bioenergy coupled to carbon capture and storage (BECCS), potential ecosystem impacts and land constraints counsel in favor of scrutinizing a “suite” of options to capture carbon dioxide, falling into three broad categories:
    • Increasing biological uptake;
    • Increasing inorganic reactions with rocks;
    • Direct air capture from the atmospheric with engineering approaches
  • The report makes eight specific policy recommendations related to GGR (see section 5 of this post)


  1. Some of the specific options examined in the report include the following:
  • Afforestation, reforestation, and forest management:
    • Potential carbon dioxide sequestration potential of these options ranges from 3-18GtCO2/yr., dependent on factors including “assumed land availability, location, forest type and management as well as economic and biophysical constraints;”
    • Large-scale forestation could pose serious environmental risks, including potential negative impacts on biodiversity if natural forests or other natural ecosystems are replaced with fast-growing or higher biomass tree plantations, as well as life-cycle impacts associated with use of energy, fertilizer, pesticides and volatile organic chemical emissions. Conversely, conversion of croplands or degraded land with forests could enhance biodiversity and produce other ecosystem benefits;
    • There is a compelling need for sound characterization of optimal locations for planting forests, as such efforts might actually increase warming in snow-covered boreal localities and regions. Moreover, potential displacement of agricultural production that might exacerbate food security must be addressed, either by a focus on agroforestry or prioritization of degraded land or previously forested land;
    • Many parties to the Paris Agreement have already incorporated forest initiatives in their Nationally Determined Contributions, representing a full quarter of mitigation pledges to date.


  • Wetland, peatland and coastal habitat restoration:
    • Peatlands and coastal wetlands store an astounding 44-71% of the globe’s terrestrial biological carbon, with large areas of these ecosystems subject to degradation that threatens carbon sequestration;
    • There is substantial experience with restoring habitats of this nature, with potential additional sequestration ranging from 0.4-18tCO2 per hectare annually, including many relatively low-cost options;
    • Restoration programs can yield important co-benefits, such protection from storm surges. However, there are also risks associated with implementation, such as decreasing surface albedo, and thus potentially increasing warming in some regions, and release of non-carbon dioxide greenhouse gases, such as methane and nitrous oxide.


  • Soil carbon sequestration:
    • Soil carbon sequestration options include crop management, nutrient management, reduction of tillage, improved grassland varieties and fire management;
    • Technical potential for soil carbon sequestration ranges from 1.1-11.4 GtCO2/yr., with more conservative estimates of 6.9 GtCO2/yr.;
    • Soil carbon sequestration could yield substantial co-benefits, including enhancing crop productivity. However, it also could pose risks and challenges, including increasing other greenhouse gas emissions and posing difficult monitoring and verification issues;
    • While there are efforts in place currently to enhance soil carbon sequestration, such as the “4 Per 1000 Initiative,” there are major challenges to scaling up such initiatives, including a lack of financial incentives, and limited knowledge of the benefits of such programs among farmers and land managers.


  • Biochar:
    • Biochar is charcoal produced by thermal decomposition of biomass at elevated temperatures in inert environments that can be applied as a soil amendment. It can facilitate storage of carbon and stabilize organic matter in soils. Studies estimate that biochar can remove 2.1-4.8 tCO2 per ton added to soils;
    • Application of biochar could yield co-benefits, including enhancement of soil fertility and stabilization of heavy metals. However, concerns have also been raised about the need for dedication of large swaths of land for production of requisite biomass, decreases in surface albedo, and potential releases of methane and nitrous oxide, though some benefits indicate the opposite in terms of this latter consideration;
    • Policy and social concerns include potential negative perceptions about the facilities used to produce biochar (“incineration in disguise”), and regulatory constraints on the amount of biochar that can be applied to soils.


  • Bioenergy with Carbon Capture and Storage:
    • Bioenergy with carbon capture and storage entails wedding biomass combustion to produce energy with carbon capture and storage technologies. Global sequestration potential could be as high as 10GtCO2/yr. However, the report cautions that injudicious management strategies and land-use choices could even result in BECCS producing a net increase in greenhouse gas emissions;
    • BECCS could require substantial amounts of land, 0.03 to 0.06 ha per tCO2, and 60 m3 per tCO2 of water. Production of dedicated bioenergy crops could substantially impact food prices and significantly impact the globe’s nitrogen cycle;
    • Substantial regulatory requirements for BECCS include crediting national emissions inventories should bioenergy feedstocks be exported and the integrity of carbon dioxide storage.


  • Ocean iron fertilization:
    • Ocean iron fertilization (OIF) entails placement of nutrients (such as iron or nitrate/phosphate) in oceans to stimulate production of phytoplankton that can take up carbon dioxide. Some of this carbon dioxide can be stored in the deep ocean when phytoplankton die and sink to the bottom in a process known as “the biological pump. The estimated potential of OIF is 3.7 GtCO2/yr., with a total ocean sequestration capacity until the end of this century of 70 to 300 GtCO2.
    • OIF risk factors could include potential ecosystem impacts of unpredictable new assemblages of plankton, toxic algal blooms, and production of methane and nitrous oxide.


  • Enhanced terrestrial weathering
    • Enhanced terrestrial weathering would seek to accelerate the natural weathering process on silicate rocks, which removes carbon dioxide from the atmosphere and releases metal ions and carbonate and bi-carbonate ions. The most discussed method to effectuate this would be milling silicate rocks containing calcium or magnesium and spreading them over large areas of managed cropland. Recent research indicates that this could remove between 0.5 and 4.0 GtCO2/yr. by 2100 if two-thirds of the most productive cropland soils were treated with basalt;
    • Basalt addition to croplands can increase food production and improve soil health. However, there are also a number of risks to human health and the environment with this process, including negative environment impacts associated with mining and processing of rocks, as well as the potential for silicosis if inhaled, decreases in water clarity.


  • Direct air capture and carbon storage (DACCS)
    • DACCS can effectuate removal of carbon dioxide from the atmosphere utilizing a “separating agent” to capture the CO2. The carbon dioxide is subsequently “regenerated” with heat or water, which results in the release of the CO2 as a high purity for stream for geological storage, injection into basaltic rock, or utilization. These technologies currently lie between pilot plant development and prototype demonstration in the field;”
    • DACCS will require substantial amounts of land, and there would be pollution impacts if fossil fuels are used in the regeneration process;
    • Major challenges to large-scale deployment of DACCS include potentially very large energy requirements, which might preclude viability unless met by renewable sources, and high costs (perhaps as high as $600/ton, though at least one company is seeking to bring this down to $100/ton).
  • Other options
    • The report also discusses several other options, including ocean alkalinity, marine BECCS, enhancement of ocean upwelling to promote phytoplankton production, and approaches that could sequester greenhouse gases other than carbon dioxide, including methane and nitrous oxide.


  1. Cross-Cutting Issues:

Reflecting the report’s advocacy of a portfolio approach to GGR deployment, it includes a section outlining seven “cross-cutting issues” which its authors argue are critical to implementing large-scale GGR. This includes the following:

  • Resources: Critical considerations in this context include potential competition between certain GGR options for the same resources, such as BECCS and forestation, imposing land requirements (for example, the upper-end of forestation scenarios could require twice as much land as is currently under cultivation, with potentially huge impacts on food prices this century), substantial water demands, and in the case of some options, such as Direct Air Capture, very high energy demands;
  • Storage: Some storage options, such as those associated with BECCS, may pose serious issues in terms of permanence. Other options provide the prospects of much longer-term storage, including mineral carbonation and reaction of carbon dioxide with limestone;
  • Environment: Environmental considerations include potential biodiversity impacts, production of greenhouse gases other than carbon dioxide with much higher global warming potential, and production of pollutants through application or due to raw materials, transport or infrastructure;
  • Science and technology: Many potential GGR options will require significant research and development given uncertainties about feasibility and scale; however, this may prove to be the most serious constraint for many GGR approaches. Other serious concerns include potential scalability of many of these options given concerns of sustainability and cost, and the security and permanence of storage of greenhouse gases;
  • Economics: Current carbon prices in most jurisdictions are too low to drive large-scale deployment of many GGR technologies. However, there is some impetus to increase carbon prices over time, with prices of $50-100 per tCO2 potentially sufficient to making many of GGR options economically viable. Regulatory mandates could also help to address market failures;
  • Legislation: The report outlines an array of legislative/regulatory requirements at the national level, including developing reporting requirements, especially for land-based options, sustainability mandates that may constraint scalar deployment of some options, and effective incorporation of GGR options in nationally determined contributions;
  • Social aspects: Societal perceptions of GGR options could limit deployment of GGR, but could also lead to a “moral hazard” that could reduce commitments to mitigation. The report suggests some of the issues that may of primary concern to the general public, including impacts of local landscapes and environments, and more broadly by societal imaginaries of “how the world should look in the future” based on overarching values
  1. Scenarios:
  • The report outlines scenarios at both the United Kingdom and international level to assess how individual GGR options and cross-cutting issues might influence the potential role of GGR in future climate response portfolios;
  • In terms of the United Kingdom, the report concludes that GGR could provide 130 MtCO2 of sequestration by 2050, assuming, inter alia, maximum deployment of BECCS and DACCS. However, this scenario would prove “challenging and costly,” including the need for application of carbon pricing mechanisms to carbon dioxide removal, establishment of subsidies to drive land practices for carbon sequestration, and research and development of a number of technologies, including advanced terrestrial weathering, biochar and direct air capture;
  • The report outlines a global scenario in which 810 GtCO2 could be sequestered by 2100. This includes large-scale deployment of forest and soil sequestration options, BECCS, DACCS, Biochar (with substantial deployment more likely at scale at the dawn of the next century), and enhanced terrestrial weathering. Some options, such as ocean alkalinity are characterized as “uncertain,” while ocean iron fertilization is deemed to be “unlikely to prove useful at scale” (because of inefficiencies of net removal to the deep ocean). Many challenges, however, are also discussed, including questions of saturation and permanence of many land-based options, which will necessitate continual management and monitoring, environmental concerns, and potential impacts on food prices in the case of forestation and BECCS.
  1. Report Recommendations:

The final section of the report outlines a number of recommendations that build on lessons learned from the development of the scenarios developed above. These include the following:

  • Continuing to press for escalated commitments to reduction of emissions of greenhouse gas emissions given the costs and social and logistical challenges attendant to large-scale deployment of GGR;
  • Implementation of a suite of GGR responses, including both existing land-based approaches, such as forestation and soil carbon enhancement, but also industrial options such as Direct Air Capture;
  • Build CCS infrastructure. This necessitate a “rapid ramp-up” of an industry that is in relative infancy, as well as substantial research and development on options that could augment sedimentary storage, such as carbonation and limestone reaction with carbon dioxide;
  • Incentivize demonstrators and early-movers to drive cost-discovery and reduction of costs. Governments should also use carbon pricing and other mechanisms to drive GGR research and deployment;
  • Establish a framework to assess sustainability of GGR deployment, including rigorous life cycle assessments and environmental monitoring;
  • Incorporate GGR into regulatory frameworks (such as the range of options that can receive government subsidies in sectors such as agriculture) and carbon trading systems;
  • Establish an international science-based standard for monitoring, reporting and verification of GGR options.



As was true in its 2009 report, the Royal Society has produced an excellent analysis of the exigencies motivating consideration of non-traditional responses to climate change, the potential risks and benefits of GGR approaches, and some of the things that society would need to do to develop these options in the future. However, there are a number of issues that could have justified more attention in the report:

  1. While there are numerous references in the report to the challenges associated with large-scale sequestration of carbon dioxide, there are only a few, and extremely cryptic, references to potential avenues for utilization, including for energy production, chemicals, fertilizers and materials. Most notably, the report failed to discuss for the roles that enhanced oil recovery (EOR) by injection of carbon dioxide might play in upscaling GGR: EOR could substantially improve the economic viability of CCS in the near term, but at the same time, it could roil the political waters by generating opposition among those who believe that EOR could derail efforts to rapidly decarbonize the world economy;
  2. The report gives extremely short shrift to so-called “Blue Carbon” options to increase carbon sequestration in coastal and ocean ecosystems, including mangrove forests, seagrass meadows or intertidal saltmarshes, as well as the potential for algae. Given the potential co-benefits of these approaches, they may have warranted more coverage;
  3. While the report includes numerous references to the Paris Agreement in the context of the NDCs, it did not discuss how its provisions for sustainability and protection of human rights might have implications for the scope and magnitude of GGR deployment. These may prove to be critical issues in terms of notions of equity and justice and potential political support, or resistance, to GGR in the future;
  4. While the report focuses on legal efforts at the national level to effectuate assessment and regulation of GGR options, it largely ignores the important role that many international treaty regimes might play, including the United Nations Convention on the Law of the Sea in the context of marine-based options; treaties for transboundary impact assessment, such as the Espoo Convention, pertinent international treaties in the context of land-use and forests, the potential role of human rights conventions in cases where GGR options could threaten the rights to food, water and subsistence.

Upcoming Negative Emissions Technologies Webinar: Synthesis Studies

On Tuesday, June 26, The Forum for Climate Engineering Assessment will host a webinar, “What We Know and Don’t Know about Negative Emissions.” The webinar will be chaired by Wil Burns, Co-Director of the Forum, and David Morrow, the Forum’s Research Director. Details are provided below. Please do not hesitate to contact me should you have any questions. Wil Burns

Join the Forum for Climate Engineering Assessment for the second installment of our “Assessing Carbon Removal” webinar series, where we will speak with three authors of a recently published systematic review of the carbon removal/negative emissions technologies research field. The study reviewed more than 6,000 documents on seven groups of technologies: bioenergy with carbon capture and storage (BECCS), afforestation and reforestation, direct air carbon capture and storage (DACCS), enhanced weathering, ocean fertilization, biochar, and carbon sequestration in soil. The authors argue that the carbon removal research field does not match the urgency of the large-scale deployment it proposes and call on researchers to expand their studies on pathways to deployment beyond the research and development stages.
The authors will discuss their findings about the state of the research field, propose areas for further research, and answer audience questions.

Dr. Jan Minx is head of the applied sustainability science working group at the Mercator Research Institute on Global Commons and Climate Change, and Priestley Chair of climate change and public policy at the University of Leeds; Dr. Sabine Fuss is head of the sustainable resource management and global change working group at the MCC; and Dr. Gregory Nemet is associate professor of public affairs and environmental studies at the University of Wisconsin at Madison

The webinar will run from 1:00 PM ET to 2:00 PM ET on Tuesday, June 26. Please register here.

Access the first webinar with Dr. Katharine Mach (Stanford University) and Janos Pasztor (Carnegie Council Geoengineering Governance Initiative). Future webinars will discuss the potential role of enhanced soil carbon sequestration, bioenergy with carbon capture and storage, direct air capture, and other technologies and their associated economic, legal, social, and political implications.

Dr. Wil Burns
Co-Executive Director, Forum for Climate Engineering Assessment
A Scholarly Initiative of the School of International Service, American University
2650 Haste Street, Towle Hall #G07
Berkeley, CA 94720
650.281.9126 (Phone)

Skype ID: Wil.Burns
Blog: Teaching Climate/Energy Law & Policy,

New Climate Attribution Study

A frequent question advanced by students is whether observed warming over the course of the past few centuries could simply be a function of “natural” or “internal” variability, a line of reasoning that is also often advanced by climate skeptics also in challenging climate mitigation policies. We have addressed this issue before here, and here.

new study in the journal Nature advances our understanding even further in the field of climate attribution by going beyond previous studies in terms of assessing the robustness of the employed model, as well as sensitivity to internal variability and uncertainties in terms of natural and anthropogenic forcings. Moreover, it reinforces the conclusions of previous studies, as well as the conclusion of the IPCC in AR5, that the lion’s share of observed warming is anthropogenic in origin. The article would be appropriate for assignment to advanced undergraduate students or graduate students.

In the study, Haustein, et al. establish a Global Warming Index based on a “multi-fingerprinting approach.” This constitutes a linear regression that utilizes observed temperature (as well as methods to assess areas without data) as the dependent variable and estimates of anthropogenic and natural drivers of climate change as independent variables.

Among the key findings in the study:

  1. Human-induced warming in May 2017, relative to 1850-1879, was +1.01C (or 1.08C utilizing a model that utilized a statistical approach to address infill regions without data);
  2. The corresponding natural externally-driven change was only -0.01-0.03C, “and hence very small in comparison to the human contribution … essentially all the observed warming since 1850-79 is anthropogenic;”
  3. The rate of human-induced warming projected to be 0.16C/decade in the past 20 years, with an uncertainty range of 0.12-0.32C/decade;
  4. While emissions stabilized during the last three years [editor’s note: not likely to be true in 2017], greenhouse forcing is likely to still have continued to increase due to non-CO2 emissions, including for methane, and perhaps a minor amount due to reduced aerosol pollution in Asia.




Building Support for Climate Change Policy: Breaking Down Misconceptions Through Hands-on Inquiry Learning

By Drew Bush and Renee Sieber

On June 10th, 2017, the New York Times reported on Gwen Beatty, a high school junior in Wellston, Ohio, who disagreed with her teacher on climate change. When he presented evidence that human emissions of greenhouse gases were causing the Earth to warm, she repeated a refrain common to many who dispute the scientific evidence tying human actions to climatic changes.

It could be natural causes. Scientists often get it wrong. Predictions of future warming could be inaccurate.

The reporter writes that if Beatty had told her math teacher that one plus one does not equal two then she would be wrong. Not all of the sciences work with the absolutes of mathematics, yet each has a way of establishing accuracy. In the public discourse on climate change—both in schools and during governmental processes—inaccuracies about climate science and global change are commonplace. A lack of public Earth and climate science understanding results in a political debate that often ignores scientific evidence of possible severe long-term impacts.

The result has been increasing concentrations of atmospheric CO2 and serious impacts for human health, the environment and the United States economy.[1] To foster a citizenry capable of engaging productively with policies addressing climate change, we believe that the public requires better understanding of the issue, how it connects to people’s lives, and what policies might benefit them in relation to it.[2],[3]

Over the past five years in McGill University’s Department of Geography and School of Environment, we’ve investigated how lessons learned through decades of science education research can be applied to improving public understandings of climate science and related mitigation/adaptation policies. Our goal has been to educate the scientific community on how to communicate climate change and to help teachers accurately present the science in school classrooms.

We reviewed the literature to look for trends and recommendations. We found that educational reformers advocate teaching climate science using the actual methods of climate scientists. This includes asking students to pose research questions, evaluate evidence-based answers or explanations, and communicate their own findings.[4], [5], [6], [7], [8], [9]

Unlike physics or chemistry, it is not easy to teach climate change this way. Climate change consists of abstract processes occurring at global and local scales. It’s difficult for students to tangibly experience climate change. To compound the problem, the causes and risks of climate change are often represented in politics and public discourse in conflicting manners. Sometimes even graduate students have trouble understanding them.[10]


Because climate scientists rely on complex procedures and technologies, new approaches to teaching climate change often adopt climate education technologies. Our approach involved an interdisciplinary group of researchers located at NASA’s Goddard Institute for Space Studies in New York, NY and McGill University’s Faculty of Education. Over the past three years, Dr. Bush has collaborated with college and secondary school educators at John Abbott College and McGill University in Montreal, QC and the American Museum of Natural History in New York, NY. He’s taught students how to conduct research on climate change using a variety of modeling technologies.


At John Abbot College, we had a control group of students and a treatment group. In our control, students learned about GCMs through a traditional lecture and worked with climate education technologies suggested by the American Association of Geographers. These included the University Corporation for Atmospheric Research’s Very, Very Simple Climate Model, NASA GISS’s Surface Temperature Analysis Page and data/visualizations from sites like the National Snow and Ice Data Center.

The treatment group of 39 students worked with Columbia University-NASA GISS’s Educational Global Climate Model (EdGCM). This software is based on an actual GCM. Dr. James Hansen first wrote about GISS’s GCM in 1983 when he used it to conduct long-range climate experiments.[11] EdGCM itself consists of a suite of user interfaces that allows students to design experiments by manipulating inputs, and then run the model and post-process and visualize more than 80 different variables. Other graduate students in Dr. Sieber’s lab have designed new interfaces for GCMs that work online and possess more intuitive user interactions.

All of the student groups posed realistic climate research questions. But only those in the treatment group interrogated the spatial components of climate impacts and its diverse relationships between human actions today and potential regional/global conditions in the future. Overall, these students demonstrated significantly greater learning gains on pre to post diagnostic exams than those in the control.

The control students showed us the power of a well-organized and clear lecture. On the post exam, they out-scored treatment students on five multiple-choice questions that tested recall of facts about GCMs. Yet only those students who had worked with EdGCM appeared highly motivated in their work and demonstrated critical thinking about the work of climate scientists and the issue of climate change.

In the New York Time story, Gwen Beatty’s father had once been a coal miner. If we are to mitigate climate change or adapt to its worst impacts, we’ll need his daughter. Her generation will require well-trained scientists, entrepreneurs, engineers and visionaries who can reshape the world’s use of energy and adapt to any social, ecological and climatic changes.

Achieving this goal means we must treat our students as individuals who possess ideas shaped by their peers and parents. To engage them with science, most will require an introduction to the scientific habits of mind common to all scientists. Such skills will be needed to navigate a world increasingly altered by changes to the Earth’s climate.

This work was supported through a Richard H. Tomlinson Fellowship in University Science Teaching and the first author’s work instructing graduate teaching workshops as a Tomlinson Project in University-Level Science Teaching Fellow at McGill University.


[1] See IPCC (2014). Summary for policymakers. In , C.B. Field, V.R. Barros, D.J. Dokken, K.J. Mach, M.D. Mastrandrea, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, & L.L. White (Eds.) Climate change 2014: Impacts, adaptation, and vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (pp. 1-32) Cambridge, UK and New York, NY: Cambridge University Press.

[2] See Bord, R. J., O’Connor, R. E., & Fisher, A. (2000). In what sense does the public need to understand global climate change?. Public Understanding of Science, 9(3), 205-218.

[3] See Bord, R. J., O’Connor, R. E., & Fisher, A. (2000). In what sense does the public need to understand global climate change?. Public Understanding of Science, 9(3), 205-218.

[4] See National Research Council (NRC). (1996). National science education standards. Washington, DC: National Academies Press.

[5] See Ministry of Education [Taiwan] (2001). Standards for nine-year continuous curriculum at elementary and junior high level in Taiwan. Taipei: Ministry of Education, R.O.C.

[6] See American Association for the Advancement of Science (AAAS) (1990). Science for all Americans: Project 2061. New York, NY: Oxford University Press.

[7] See Department for Education/Welsh Office (DFE/WO) (1995). Science in the national curriculum (1995). London: HMSO.

[8] See NGSS Lead States. (2013). Next Generation Science Standards: For states, by states. Washington, DC: The National Academies Press.

[9] See Olson, S. & Loucks-Horsley, S. (Eds.) (2000). Inquiry and the national science education standards: A guide for teaching and learning. Washington, DC: National Academies Press.

[10] See Sterman, J. D. (2008). Risk communication on climate: Mental models and mass balance. Science, 322(5901), 532-533.

[11] See Hansen, J., Russell, G., Rind, D., Stone, P., Lacis, A., Lebedeff, S., Ruedy R. & Travis, L. (1983). Efficient three-dimensional global models for climate studies: Models I and II. Monthly Weather Review, 111(4), 609-662.



Tackling the Issue of Climate Attribution: New Study

A couple of days ago there was a feisty exchange on Fox News between host Tucker Carlson and Bill Nye (“the Science Guy”). Carlson challenged Nye to establish that climatic changes are linked to anthropogenic greenhouse gas emissions, and quite frankly, Nye struggled to articulate a response.

However, Mr. Nye, as well as instructors addressing this critical, and ever-abiding issue, might benefit from the results of a new study published in the journal The Anthropocene Review. What I found particularly salutary about this piece was its explanation of why the current bout of climatic change could be linked to different factors than factors than those that precipitated climate change in the past.

Among the conclusions of the study:

  • During the period of the existence of the Earth’s biosphere, the primary drivers of earth system change have been two external force: astronomical (“forces that affect insolation and relate to solar irradiance include orbital eccentricity, obliquity and precession driven by gravitation effects of the sun and other planets”) and geophysical (forces that include “volcanic activity, weathering and tectonic movement”);
    • In the past 2.588 billion years, climate forcing has been largely controlled by cyclical variation in Earth’s orbit and other astronomical forces, and irregular geophysical events, such as volcanic eruptions;
    • Under current astronomical forcing and greenhouse gas concentrations in pre-industrial levels, we would have anticipated Holocene-like conditions for approximately another 50,000 years
  • Internal dynamics, including biospheric evolutionary processes, can also drive the Earth System, however. Such factors are particularly important given their impacts on carbon dioxide, which exerts a substantial influence on climate.
    • At this point, human activity (denominated as “H”), as a subset of internal processes, has reached a profound influence on earth system processes. Indeed, it has become the dominant driver of the rate of change of the Earth System. This has included a doubling of the amount of reactive nitrogen in the system relative to pre-industrial levels, and a huge change in ocean carbonate chemistry.
    • In the context of climate change, atmospheric concentrations in recent years have increased 100x faster than the most rapid increases during last glacial termination. Methane levels have risen at a rate that is more than double the rates of the past 800,000 years. This has resulted in temperature increases 70x the baseline over the course of the past 100 years, and 170 the Holocene baseline rate over the course of the past 45 years
  • Anthropogenic impacts crossed a critical threshold around 1950 during the “Great Acceleration” of greenhouse gas emissions, with human factors “usurping” the impacts of other factors “entirely.”
  • Though it may come as cold comfort to humankind, while human factors may control earth systems over the course of the next tens of thousands of years, astronomical, geophysical and other internal factors are likely to ultimately re-assert control over the system.

It might be interesting to couple this reading for students with another recently published study seeking to assess the statistical likelihood that recent warming is primarily attributable to rising levels of anthropogenic emissions. This would be an excellent opportunity to tease out methodological considerations associated with so-called “climate attribution” studies.

Tracking Current and Future Progress in Fulfilling Paris

Nature PetersWhile there are numerous analyses indicating that current National Determined Contributions (NDCs) made the Parties to the Paris Agreement do not put the world on track to meet the treaty’s objectives of “holding the increase in the global average temperature to well below 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 °C above pre-industrial levels.” However, very few efforts have been made to date to ascertain how to track progress in meeting the temperature targets of Paris. This can be a critical component of informing the treaty’s global stocktaking process (Art. 14) and provisions to increase the ambition of commitments (Art. 3; 4). In a new study published in the journal Nature, Peters, et al. employ a nested structure of a group of indicators intended to track the progress of parties to Paris in meeting their Paris obligations, including aggregated progress, country-level decompositions to track emerging trends, and technology diffusion.

Among the conclusions of the study:

  • While global carbon dioxide emissions have been flat for the past three years (projected to be 36.4 GtCO2 in 2016), cumulative emissions continue to rise, which will preclude meeting Paris’s objectives given the need for rapid declines in emissions, and ultimately zero emissions;
  • While Chinese emissions have been largely stable recently, and US and EU emissions have declined in the past few years, it’s unclear if these are long-term trends, or largely attributable to weak economic growth or other short-term factors.
    • There is empirical evidence of emerging declines in carbon intensity globally, including the China, the United States and the European Union
  • While the growth of the use of renewable energy has been substantial in recent years, including more than 50% of total energy growth in 2015, it will prove difficult for renewable energy to supply annual energy growth in the short term absent further declines in global energy use. Renewable energy alone may also not be sufficient to keep global temperatures below 2C given physical constraints to large-scale deployment and limited prospects for use in certain sectors, such as agriculture;
  • While it is possible to keep temperature increases to 2C or below with relatively high fossil fuel energy use, this scenario is predicated on substantial reliance on bioenergy, coupled with large-scale deployment of carbon capture and sequestration (CCS). However, this assumes that bioenergy can be sustainably produced and made carbon-neutral. It’s also predicated on huge scale-up of CCS in conjunction with bioenergy (BECCS). This may require as many as 4000 facilities by 2030 compared with the tens currently proposed by 2020. Scale-up of this magnitude may prove to be a large challenge given social resistance and inadequate assessment of technological risks;
  • Studies indicate that current emissions pledges may “quickly deviate” from what is required to conform to the 2C objective. Should some technologies lag in deployment, others will have to ramp up more quickly. These is also a lack of scenarios assessing the prospects for transformational changes in lifestyle and behaviors, other forms of carbon dioxide removal, and solar radiation management geoengineering.

Among potential questions for classroom discussion are the following:

  1. What are the challenges associated with large-scale deployment of bioenergy and carbon capture and sequestration/storage? What policy measures could help to ameliorate these challenges;
  2. What are the potential benefits of solar radiation management geoengineering; what are the potential risks;
  3. What measures could be taken to accelerate market penetration of renewable energy?

Poster’s note: There is an interview with Glen Peters that further explicates some of the findings of this study.

Global Temperatures Over the Next Few Thousand Years?

Recent studies have projected temperature increases of 2.7-3.5C by 2100 associated with the current Intended Nationally Determined Contributions of the parties to the United Nations Framework Convention on Climate Changnaturesnydere. However, the sobering reality is that the inertia of the climate system ensures that temperatures will continue to increase well beyond this in the centuries and millennia to come. A new study by Stanford scholar Carolyn W. Snyder suggests that temperature increases beyond 2100 may be truly alarming. Synder’s study sought to reconstruct global average surface temperatures over the  past 2 million years using a spatially weighted proxy reconstruction of globally averaged surface temperature.

Among the study’s findings:

  1. Based on estimated greenhouse gas radiative forcing derived from proxy reconstruction, a doubling of atmospheric carbon dioxide (3 W m-2) would ultimately translate into a 9C increase in temperature (7-13C, 95% interval);
  2. Stabilization of atmospheric concentrations of greenhouse gases at today’s levels may already have committed the globe to 5C (3-7C, 95% credible interval)over the next few thousand years.

The study’s findings could provide good grist for class discussion on several issues, including whether it’s possible to substantially bend the projected temperature curve through more aggressive de-carbonization of the world economy, this generation’s obligations, if any, to generations over the next few thousand years, and the potential role of climate geoengineering, including negative emissions technologies, in potentially reversing course of temperature projections.


Call for Resources: Teaching Climate Law

I administer the Climate Law Teaching Resources site for the IUCN’s Academy of Environmental Law: The site includes syllabi and climate negotiation simulations for use in the classroom.

If you have pertinent materials you are willing to share with the teaching community, please send them to me and I will have them posed promptly on the site. Thanks, wil