Jacobson, Mark (2019). Why Carbon Capture and Direct Air Capture Cause More Damage than Good to Climate and Health

Author:  Mark Z. Jacobson Dept. of Civil & Environmental Engineering, Stanford University, Stanford, CA, USA.  Email: jacobson@stanford.edu

Abstract:  Spending money on carbon capture and storage or use (CCS/U) and synthetic direct air capture and storage and use (SDACCS/U) increases carbon dioxide equivalent (CO2e) emissions, air pollution, and costs relative to spending the same money on clean, renewable electricity replacing fossil or biofuel combustion. In a recently published paper in Energy and Environmental Sciences on this issue (doi:10.1039/c9ee02709b), I analyzed data from an existing coal-CCU plant and an SDACCU plant. A net of only 10.8% of the CCU plant’s CO2e emissions and 10.5% of the CO2 removed from the air by the SDACCU plant are captured over 20 years, and only 20-31%, are captured over 100 years. The low net capture rates are due to uncaptured combustion emissions from natural gas used to power the equipment, uncaptured upstream emissions, and, in the case of CCU, uncaptured coal combustion emissions. Moreover, the CCU and SDACCU plants both increase air pollution and total social costs relative to no capture. Using wind to power the equipment reduces CO2e relative to using natural gas but still allows air pollution emissions to continue and increases the total social cost relative to no carbon capture. Conversely, using wind to displace coal without capturing carbon reduces CO2e, air pollution, and total social cost substantially. Further, using wind to displace coal reduces more CO2e than using the same wind to power the capture equipment. As such, spending money on wind powering carbon capture always increases CO2e compared with spending on the same wind replacing fossil fuels or biofuels. In sum, CCU and SDACCU increase or hold constant air pollution health damage and reduce little carbon before even considering sequestration or use leakages of carbon back to the air. Spending on capture rather than wind replacing either fossil fuels or bioenergy always increases CO2e, air pollution, and total social cost substantially. No improvement in CCU or SDACCU equipment can change this conclusion while fossil power plant emissions exist, since carbon capture always incurs an equipment cost never incurred by wind, and carbon capture never reduces, instead mostly increases, air pollution and fuel mining, which wind eliminates. Once fossil power plant emissions end, CCU (for industry) and SDACCU social costs need to be evaluated against the social costs of natural reforestation and reducing nonenergy halogen, nitrous oxide, methane, and biomass burning emissions. 

Read Jacobson’s complete paper in Energy & Environmental Science. 


Busch et al. (2019). Reforestation is a Cost-Effective Climate Solution

Authors: Jonah Busch, Jens Engelmann, Susan C. Cook-Patton, Bronson W. Griscom, Timm Kroeger, Hugh Possingham, & Priya Shyamsundar

Full citation: Busch, J., Engelmann, J., Cook-Patton, S. C., Griscom, B. W., Kroeger, T., Possingham, H., & Shyamsundar, P. (2019). Potential for low-cost carbon dioxide removal through tropical reforestation. Nature Climate Change9(6), 463.

Abstract: Reforestation offers one of the best ways to remove carbon dioxide from the atmosphere, turning it into solid carbon through photosynthesis and storing it in tree trunks, branches, roots, and soil. Reforestation can be a cost-effective climate solution, too, according to a recent study in Nature Climate Change of the cost of reforestation across 90 tropical countries that I conducted with colleagues at The Nature Conservancy and the University of Wisconsin.  

According to our analysis, a hypothetical tropics-wide carbon price of $20 per ton of carbon dioxide—around the current price in European and Californian carbon markets—would incentivize land users to increase reforestation by enough to remove an additional 5.7 billion tons of carbon dioxide (5.6%) from 2020-2050, equivalent to thirty years of current greenhouse gas emissions from Kuwait (Figure 1). 

A higher price of $50-100 per ton of carbon dioxide—consistent with what’s needed to achieve the Paris Climate Agreement—would increase removals by between 15.1 and 33.3 billion tons of carbon dioxide (14.8-32.5%) between 2020-2050—equivalent to thirty years of current emissions from the United Kingdom or Japan

We came to our conclusions by simulating the effects of payments for increased carbon removals on future land-cover changes, accounting for geographical differences across sites, and assuming that land users would be as responsive to changes in carbon prices as they were to historical variation in agricultural prices. 

The cost of reforestation compares favorably to other “negative emissions technologies” (NETs). We compared our cost estimates for tropical reforestation to Sabine Fuss and colleagues’ cost estimates for NETs that may become operational by 2050. On a cost-per-ton basis, tropical reforestation is more cost-effective in 2050 than bio-energy with carbon capture and storage (BECCS) and direct air carbon capture and storage (DACCS). It’s as cost-effective in 2050 as biochar, and less cost-effective than enhanced weathering or soil carbon sequestration. 

On average, avoiding deforestation is 7-10 times more cost-effective than reforestation, but reforestation is more cost-effective than avoiding deforestation in some places. Reforestation offers more abatement than avoided deforestation at $20 per ton in 21 out of 90 tropical countries studied.  

Tropical reforestation and avoided deforestation combined offer up to one-third of a comprehensive, cost-effective, near-term solution to climate change. The combined potential of increasing removals from reforestation and reducing emissions from deforestation at $20-50-100 per ton is 161-123-192 billion tons from 2020-2050. Averaged out on a per-decade basis, those levels of mitigation represent, respectively, 10-21-33% of the 197 billion tons of mitigation needed from 2020-2030 to hold global warming below 2 °C. This supports the finding of a landmark 2017 study by Bronson Griscom and colleagues, which found that twenty natural climate solutions worldwide offer more than one-third of the cost-effective near-term solution to climate change.

Based on these findings, tropical countries should accelerate reforestation, and developed countries should step up international finance for reforestation, especially through provisions of the Paris Climate Agreement related to reducing emissions from deforestation and forest degradation, “plus” re-growing forests (REDD+).

Graphical representation of the information presented in the abstract.Figure 1. Marginal abatement cost curves for increased removals from tropical reforestation and reduced emissions from avoided deforestation.

Read Busch et al.’s full paper in Nature Climate Change. 

Carton, Wim (2019). “Fixing” Climate Change by Mortgaging the Future: Negative Emissions, Spatiotemporal Fixes, and the Political Economy of Delay

Full citation: Carton, W. (2019). “Fixing” Climate Change by Mortgaging the Future: Negative Emissions, Spatiotemporal Fixes, and the Political Economy of Delay. Antipode51(3), 750-769.

Abstract: Modeling studies suggest that successful climate change mitigation now depends on the roll-out of “negative emissions”, that is, the large-scale removal of carbon dioxide from the atmosphere through a range of proposed technologies. This idea has been extensively criticized by other scientists for being unfeasible and unjust. Among others, a reliance on negative emissions over more short-term emission reduction strategies transfers the costs of mitigation, and the risks of potential failure, to future generations. In this article, I add to this literature by exploring the political economic effects that a focus on negative emissions has, or might have in the future. Building on a rich theoretical tradition within geography, and drawing on a literature review and a contemporary example, I highlight the risk that negative emissions become an active delaying strategy for the fossil fuel industry. I use a recent scenario exercise (‘Sky’) by the oil and gas company Shell to demonstrate how the mere promise of negative emissions can be used by companies to persuade investors and policy makers that substantial, continued use of fossil fuels is compatible with the goals of the Paris Agreement. The paper seeks to explain this dynamic by unpacking some of the assumptions that underlie the models used by scientists to create mitigation scenarios. I draw particular attention to the models’ methodological basis in cost-optimizing economics as one of the reasons why negative emissions scenarios appear to align so easily with the economic interests of companies such as Shell. The paper also makes a theoretical contribution to the field of environmental geography by conceptualizing these dynamics more generally. In the conclusion, I call for more critical attention to the ideological assumptions that underlie mainstream scenario exercises, and the way that these further certain social and economic interests over others.

Read Carton’s complete paper in Antipode.

Smith et al. (2019) How to measure, report and verify soil carbon change to realise the potential of soil carbon sequestration for atmospheric greenhouse gas removal

Authors: Pete Smith1, Jean-Francois Soussana2, Denis Angers3, Louis Schipper4, Claire Chenu5, Daniel P. Rasse6, Niels H. Batjes7, Fenny van Egmond7, Stephen McNeill8, Matthias Kuhnert1, Cristina Arias-Navarro2, Jorgen E. Olesen9, Ngonidzashe Chirinda10, Dario Fornara11, Eva Wollenberg12, Jorge Álvaro-Fuentes13, Alberto Sanz-Cobena14, Katja Klumpp15

Full citation: Smith, P., Soussana, J. F., Angers, D., Schipper, L., Chenu, C., Rasse, D. P., … & Arias‐Navarro, C. (2019). How to measure, report and verify soil carbon change to realize the potential of soil carbon sequestration for atmospheric greenhouse gas removal. Global change biology.

Abstract:  One proposed option for removal of carbon dioxide from the atmosphere is by increasing the amount of carbon retained in the soil organic matter, an option known as soil organic carbon sequestration. Given that soils already contain a lot of carbon, and changes in soil organic carbon are slow, it is difficult to measure increases in soil carbon against the large background soil carbon stock. Because of this difficulty in measuring changes in soil organic carbon, a key barrier to implementing programmes to increase soil organic carbon is the need for credible and reliable measurement/monitoring, reporting and verification platforms. We review methods for measuring soil organic carbon change directly in soils, we examine novel developments for quantifying soil organic carbon change, and describe how surveys, long-term experiments and chronosequences (sites of different ages with changes at various stages of carbon gain) can be used for testing models and as benchmark sites in global frameworks to estimate soil organic carbon change. We review measurement/monitoring, reporting and verification platforms for soil organic carbon change already in use and describe a new vision for a global framework for measurement/monitoring, reporting and verification platform of soil organic carbon change. The proposed platform builds on existing repeat soil surveys, long-term experiments, remote sensing, modelling and novel measurement methods and could be applied at national, regional or global scales.

A graphical representation of the information presented in the accessible abstract.

Read Smith et al.’s full paper in Global Change Biology.

Author affiliations: 

1 Institute of Biological & Environmental Sciences, University of Aberdeen, 23 St Machar Drive, Aberdeen, AB24 3UU, UK

2 INRA, 147 rue de l’Université 75338 Paris Cedex 07, France

3 Agriculture and Agri-Food Canada, 2560 Hochelaga Blvd Quebec, Quebec G1V 2J3, Canada

4 Environmental Research Institute, University of Waikato, Hamilton, Private Bag 3105, Hamilton 3240, New Zealand

5 INRA, AgroParisTech. Bât. EGER F- 78850 Thiverval-Grignon, France

6 Norwegian Institute of Bioeconomy Research (NIBIO), Høgskoleveien 7, 1433 Ås, Norway 

7 ISRIC – World Soil Information, Droevendaalsesteeg 3. 6708PB Wageningen, The Netherlands

8 Manaaki Whenua – Landcare Research, PO Box 69040, Lincoln, New Zealand

9 Department of Agroecology, Aarhus University, Blichers Allé 20, Tjele, Denmark  

10 International Center for Tropical Agriculture (CIAT), A.A. 6713, Cali, Colombia

11 Agri-Food and Biosciences Institute, Belfast, Northern Ireland, Newforge Lane, BT9 5PX, Belfast, UK

12 CGIAR CCAFS Programme, University of Vermont (UVM), Burlington, VT 05405, USA

13 Soil and Water Department, Spanish National Research Council (CSIC) PO Box 13034, 50080 Zaragoza, Spain

14 Research Center for the Management of Environmental and Agricultural Risks (CEIGRAM), Universidad Politécnica de Madrid, Madrid 28040, Spain

15 INRA, VetAgro-Sup, UCA, Ecosystème Prairial, Clermont Ferrand, France

Hohlwegler, P. (2019). Moral Conflicts of several “Green” terrestrial Negative Emission Technologies regarding the Human Right to Adequate Food

Full Citation: Hohlwegler, P. (2019). Moral Conflicts of several “Green” terrestrial Negative Emission Technologies regarding the Human Right to Adequate Food–A Review. Advances in Geosciences, 49, 37-45.

Abstract: In 2015, 195 nations of the World signed upon the Paris Agreement, thereby agreeing to do their best to limit average global warming to a maximum of 2 °C until 2100. This would prevent great damage to many ecosystems and would further reduce storms and droughts. Current efforts, however, to mitigate climate change are not enough and are likely to result in  an average warming of about 3 °C until 2100. To still achieve the 2°C target set in the Paris Agreement, it seems necessary to alter the climate in a technical way. There are two kinds of technologies—Solar Radiation Management (SRM) and Carbon Dioxide Removal (CDR)—each comprising several methods. SRM methods work against global warming but do not combat the source of climate change which are human-made greenhouse gas emissions, especially carbon dioxide (CO2). Not doing something against the source of global warming, however, is dangerous because warming is not the only consequence of climate change that might affect life on Earth in a negative way. Oceans are getting more acidic and become dead zones. Air quality decreases, thereby increasing the likeliness of diseases. Therefore, it would be better to combat climate change at its source. CDR methods do this by reducing the concentration of the most important greenhouse gas—CO2—in the air. Many CDR methods further rely on naturally occurring processes, like photosynthesis and the weathering of rocks. Due to these reasons, they may be labelled as “green” methods. Even though such “green” methods may appear morally good at first sight, they might also provide harmful side-effects. Reviewing recent publications, I researched whether three of these “green” methods—Bioenergy with Carbon Capture and Storage (BECCS), Afforestation and Reforestation, Enhanced Weathering—would impact agricultural food production in a negative way and thereby aggravate the problem of hunger in the World. This would then be a case of moral conflict regarding the human right to adequate food. My results were that Enhanced Weathering would not trouble agricultural food production but would even be beneficial to soils and thus promote agricultural growth. But using this method as a single solution to climate change would require large amounts of energy which in turn would produce emissions and thus counteract the beneficial effects. BECCS, the most prominent CDR method, as well as Afforestation and Reforestation, however, would impact agricultural food production in a negative way because both would demand large areas to grow either plants or trees. Given that already more than 820 million people suffer from hunger, a reduction of global agricultural area and thus available food would be a serious issue which is morally not permissible. Therefore, BECCS, as well as Afforestation and Reforestation, are also not suitable to be single solutions against climate change. However, every method researched in this paper might contribute to a more comprehensive strategy to mitigate climate change.

Read Patrick Hohlwegler’s complete paper in Advances in Geosciences.

Jacobson & Sanchez, D. L. (2019). Opportunities for Carbon Dioxide Removal Within the United States Department of Agriculture.

Full citation: Jacobson, R., & Sanchez, D. L. (2019). Opportunities for Carbon Dioxide Removal Within the United States Department of Agriculture. Frontiers in Climate1, 2.

Abstract: Over the next century, atmospheric carbon dioxide removal (CDR) will be necessary to limit the most significant impacts of catastrophic climate change. Nonetheless, many CDR technologies and land management strategies currently remain at the research and development stage, with minimal capacity for commercialization and deployment. Moreover, farming, ranching, and forestry communities in the United States sit at the front lines of climate change impacts and responses. Fortunately, some of the most inexpensive and promising opportunities for CDR deployment exist within the ability of managed ecosystems, agricultural soils, and forest biomass and products to sequester carbon dioxide. In particular, terrestrial atmospheric carbon dioxide removal (CDR) can reduce the most extreme impacts of climate change while increasing resilience to extreme weather.

Currently, many CDR technologies and land management strategies are still at the research and development (R&D) phase, and lack sufficient federal support to reach widespread deployment. Here, we summarize the United States Department of Agriculture’s (USDA) previous and ongoing efforts to incorporate CDR relevant R&D within their research, education, and economics mission, as well as opportunities to refocus and expand existing programs. Potential future actions to expand CDR R&D capabilities include: 1) the establishment of a new extramural research agency and a new intramural technology commercialization program within USDA, 2) improved coordination between the Foundation for Food and Agriculture (FFAR) and USDA, 3) improved intra-agency and inter-agency coordination, and 4) congressional action to establish and fund new CDR programs within USDA. Finally, we provide an assessment of how changes in funding through legislative actions could support USDA’s leadership on applied RD&D for land-use CDR.

We find that new agencies and programs, such as an Advanced Research Projects Agency for Agriculture and an Agriculture “I-Corps” technology incubator and entrepreneurial training program, could provide breakthrough advances for land-use CDR at relatively low costs. Additionally, we find that many USDA agencies and offices are well suited and equipped to incorporate the National Academies of Sciences, Engineering, and Medicine’s (NASEM) recommended research programs for carbon sequestration in managed and agricultural lands. In order to implement many of these recommended programs, congressional action will be necessary in order to increase funding to certain agencies or provide explicit direction through appropriations report language. Since all existing USDA programs and agencies are not necessarily well equipped to carry out research on specific land-use CDR research topics, in some cases new programs will also need to be developed in order to execute the recommended research projects. Still, some land-use CDR RD&D activities will require external collaboration or partnerships with existing federal departments or external foundations in order to optimize the effectiveness of USDA research. Specifically, we recommend that for certain projects, USDA should partner and/or more effectively coordinate and collaborate with the Department of Energy and the Foundation for Food and Agriculture.

Nonetheless, we argue that many USDA offices and agencies are well positioned to pursue many land-use CDR R&D projects identified and detailed by NASEM as crucial to scaling and commercializing CDR technologies and land management strategies. Although we find many existing agencies will require some expansion, modification, or increased support, it is evident that USDA will be crucial to, and play a major role in, mitigating emissions from the agricultural sector and increasing carbon sequestration across the United States.

Read Jacobson et al.’s complete paper in Frontiers in Climate.