The potential cost of regulation of methane and nitrous oxide emissions in U.S. agriculture

Background Most studies on the environmental impacts of agriculture have attempted to measure environmental impacts but have not assessed the ability of the sector to reduce or mitigate such impacts. Only a few studies have examined greenhouse gas emissions from the sector. This paper assesses the ability of states in the U.S. to reduce agricultural emissions of methane and nitrous oxide, two major greenhouse gases (GHGs) with important global warming potential. Methods The analysis evaluates Färe’s PAC (pollution abatement cost) for each state and year, a measure of the potential opportunity costs of subjecting the sector to GHG emissions regulation. We use both hyperbolic and directional distance functions to specify agricultural technology with good and bad outputs. Results and conclusions We find that such regulations might reduce output by an average of about 2%, although the results for individual states vary quite widely.

Exploratory Study on Modelling Agricultural Carbon Emissions in Ireland

In 2020 Ireland missed its EU climate emissions target and without additional measures will not be on the right trajectory towards decarbonisation in the longer 2030 and 2050 challenges. Agriculture remains the single most significant contributor to overall emissions in Ireland. In the absence of effective mitigating strategies, agricultural emissions have continued to rise. The purpose of the review is to explore current research conducted in Ireland regarding environmental modelling within agriculture to identify research gap areas for further research. 10 models were selected and reviewed regarding modelling carbon emissions from agriculture in Ireland, the GAINS (Air pollution Interactions and Synergies) model used for air pollutants, the JRC-EU-TIMES, (Joint Research Council-European Union-The Integrated MARKAL-EFOM System) and the Irish TIMES model used for energy, the integrated modelling project Ireland (GAINS & TIMES), the environmental, economic model ENV-Linkages and ENV-Growth along with the IE3 and AGRI-I models. The review found that data on greenhouse gas emissions for 2019 reveals that emissions can be efficiently lowered if the right initiatives are taken. More precise emission factors and adaptable inventories are urgently needed to improve national CO2 reporting and minimise the agricultural sector’s emissions profile in Ireland. The Climate Action Delivery Act is a centrally driven monitoring and reporting system for climate action delivery that will help in determining optimal decarbonisation from agriculture in Ireland. Multi-modelling approaches will give a better understanding of the technology pathways that will be required to meet decarbonisation ambitions.

Pathways, targets and temporalities: Analysing English agriculture's net zero futures

Net zero emissions targets are of growing international relevance given their increasing uptake by governments across the world. This article analyses net zero targets as a distinctly future-oriented approach to environmental governance. It does so from a critical perspective, examining whether net zero targets serve to reproduce the existing temporalities of environmental policymaking or whether they represent a break with current practices and, in turn, develop new temporalities and novel ways of engaging with the future. In order to do this, this article focuses on efforts to reduce agricultural emissions in England to net zero. In 2019 the United Kingdom introduced legislation requiring a reduction of greenhouse gas emissions to net zero by 2050. This, in turn, has encouraged actors in the food system to produce various imagined pathways to net-zero agriculture. This article critically analyses how these imagined pathways are discursively produced by influential actors within this sphere through a critical discourse analysis of recent grey literature produced by Defra, the Climate Change Committee and the National Farmers’ Union. It asserts that, to an extent, the net zero and target oriented approaches enshrined in current environmental policymaking represent the ongoing reproduction of both an ‘empty’ modernist future with some post-political dimensions. This assessment is, however, nuanced by recognising the tensions that emerge within and between the state and non-state institutions producing these discourses. Ultimately, however, the net zero transition draws actors together around a techno-optimistic vision of an agricultural future defined by sustainable intensification and negative emissions technologies. In doing so, it serves to suppress calls for transformative change in agriculture based on social as well as material change.

Viewpoints on Cooperative Peatland Management: Expectations and Motives of Dutch Farmers

The European Union (EU) is globally the second highest emitter of greenhouse gases from drained peatlands. On the national level, 15% of agricultural peat soils in the Netherlands are responsible for 34% of agricultural emissions. Crucial to any successful policy is a better understanding of the behavioral change it will bring about among the target groups. Thus, we aim to explore farmers’ differing viewpoints to discuss how policy and planning can be improved to ensure landscape-scale climate mitigation on agriculturally used peatlands. Q methodology was used to interview fifteen farmers on Dutch peat soils, whereby 37 statements were ranked in a grid according to their level of agreement. Factor analysis revealed three main viewpoints: farmers with a higher peat proportion show an urgency in continuing to use their land (‘cooperative businesspeople’), while ‘independent opportunists’ are wary of cooperation compromising their sense of autonomy. Farmers who are ‘conditional land stewards’ are open to agriculture without drainage but require appropriate payments to do so. Future policy design must focus on providing support to farmers that go beyond compensation payments by providing information about funding sources as well as potential business models for peatland uses with raised water tables.

Making Agriculture Carbon Neutral Amid a Changing Climate: The Case of South-Western Australia

Making Australian agriculture carbon neutral by 2050 is a goal espoused by several agricultural organisations in Australia. How costly might it be to attain that goal, especially when adverse climate change projections apply to agriculture in southern Australia? This study uses scenario analysis to examine agricultural emissions and their abatement via reforestation in south-western Australia under projected climate change. Most scenarios include the likelihood of agricultural emissions being reduced in the coming decades. However, the impact of projected adverse climate change on tree growth and tree survival means that the cost of achieving agricultural carbon neutrality via reforestation is forecast to increase in south-western Australia. Agricultural R&D and innovation that enable agricultural emissions to diminish in the coming decades will be crucial to lessen the cost of achieving carbon neutrality. On balance, the more likely scenarios reveal the real cost of achieving carbon neutrality will not greatly increase. The cost of achieving carbon neutrality under the various scenarios is raised by an additional AUD22 million to AUD100 million per annum in constant 2020 dollar terms. This magnitude of cost increase is very small relative to the region’s gross value of agricultural production that is regularly greater than AUD10 billion.

Effective Mainstreaming of Agricultural Emissions into Climate Action Agenda: The Case of Institutions and Smallholder Dairy Production Systems, Western Kenya

Small-scale farming production systems are integral drivers of global sustainability challenges and the climate crisis as well as a solution space for the transition to climate compatible development. However, mainstreaming agricultural emissions into a climate action agenda through integrative approaches, such as Climate Smart Agriculture (CSA), largely reinforces adaptation–mitigation dualism and pays inadequate attention to institutions’ linkage on the generation of externalities, such as Greenhouse Gas (GHG) emissions. This may undermine the effectiveness of local–global climate risk management initiatives. Literature data and a survey of small-scale farmers’ dairy feeding strategies were used in the simulation of GHG emissions. The effect of price risks on ecoefficiencies or the amount of GHG emissions per unit of produced milk is framed as a proxy for institutional feedbacks on GHG emissions and effect at scale. This case study on small-scale dairy farmers in western Kenya illustrates the effect of local-level and sectoral-level institutional constraints, such as market risks on decision making, on GHG emissions and the effectiveness of climate action. The findings suggest that price risks are significant in incentivising the adoption of CSA technologies. Since institutional interactions influence the choice of individual farmer management actions in adaptation planning, they significantly contribute to GHG spillover at scale. This can be visualised in terms of the nexus between low or non-existent dairy feeding strategies, low herd productivity, and net higher methane emissions per unit of produced milk in a dairy value chain. The use of the Sustainable Food Value Chain (SFVC) analytical lens could mediate the identification of binding constraints, foster organisational and policy coherence, as well as broker the effective mainstreaming of agricultural emissions into local–global climate change risk management initiatives. Market risks thus provide a systematic and holistic lens for assessing alternative carbon transitions, climate financing, adaptation–mitigation dualism, and the related risk of maladaptation, all of which are integral in the planning and implementation of effective climate action initiatives.

Nitrous oxide respiring bacteria in biogas digestates for reduced agricultural emissions

Inoculating agricultural soils with nitrous oxide respiring bacteria (NRB) can reduce N2O-emission, but would be impractical as a standalone operation. Here we demonstrate that digestates obtained after biogas production are suitable substrates and vectors for NRB. We show that indigenous NRB in digestates grew to high abundance during anaerobic enrichment under N2O. Gas-kinetics and meta-omic analyses showed that these NRB’s, recovered as metagenome-assembled genomes (MAGs), grew by harvesting fermentation intermediates of the methanogenic consortium. Three NRB’s were isolated, one of which matched the recovered MAG of a Dechloromonas, deemed by proteomics to be the dominant producer of N2O-reductase in the enrichment. While the isolates harbored genes required for a full denitrification pathway and could thus both produce and sequester N2O, their regulatory traits predicted that they act as N2O sinks in soil, which was confirmed experimentally. The isolates were grown by aerobic respiration in digestates, and fertilization with these NRB-enriched digestates reduced N2O emissions from soil. Our use of digestates for low-cost and large-scale inoculation with NRB in soil can be taken as a blueprint for future applications of this powerful instrument to engineer the soil microbiome, be it for enhancing plant growth, bioremediation, or any other desirable function.

Offsetting unabated agricultural emissions with CO2 removal to achieve ambitious climate targets

The Representative Concentration Pathway 2.6 (RCP2.6), which is broadly compatible with the Paris Agreement’s temperature goal by 1.5–2°C, contains substantial reductions in agricultural non-CO2 emissions besides the deployment of Carbon Dioxide Removal (CDR). Failing to mitigate agricultural methane and nitrous oxide emissions could contribute to an overshoot of the RCP2.6 warming by about 0.4°C. We explore using additional CDR to offset alternative agricultural non-CO2 emission pathways in which emissions either remain constant or rise. We assess the effects on the climate of calculating CDR rates to offset agricultural emission under two different approaches: relying on the 100-year global warming potential conversion metric (GWP100) and maintaining effective radiative forcing levels at exactly those of RCP2.6. Using a reduced-complexity climate model, we find that the conversion metric leads to a systematic underestimation of needed CDR, reaching only around 50% of the temperature mitigation needed to remain on the RCP2.6 track. This is mostly because the metric underestimates, in the near term, forcing from short-lived climate pollutants such as methane. We test whether alternative conversion metrics, the GWP20 and GWP*, are more suitable for offsetting purposes, and found that they both lead to an overestimation of the CDR requirements. Under alternative agricultural emissions pathways, holding to RCP2.6 total radiative forcing requires up to twice the amount of CDR that is already included in the RCP2.6. We examine the costs of this additional CDR, and the effects of internalizing these in several agricultural commodities. Assuming an average CDR cost by $150/tCO2, we find increases in prices of up to 41% for beef, 14% for rice, and 40% for milk in the United States relative to current retail prices. These figures are significantly higher (for beef and rice) under a global scenario, potentially threatening food security and welfare. Although the policy delivers a mechanism to finance the early deployment of CDR, using CDR to offset remaining high emissions may well hit other non-financial constraints and can thus only support, and not substitute, emission reductions.

The effects of the Syrian civil war on atmospheric NH3 as seen from IASI

<p>The Syrian civil war started in 2011, with dramatic social, political, economic, and environmental consequences over the whole area of Syria and nearby countries. Agriculture, in particular, suffered massively. Several studies used satellite-retrieved data and imagery to examine the spatio-temporal changes in the region, due to the civil war. For instance, open-source satellite imagery could show the damage in urban areas, and provide an estimate of the number of people affected by the crisis.</p><p>In this study, we investigate the impacts of the Syrian civil war on atmospheric ammonia (NH<sub>3</sub>) emitted from industrial and agricultural activities during the 2008-2019 period. Our analyses are based on the NH<sub>3</sub> measurements from the IASI instruments onboard the Metop satellites. Firstly, land-use changes and a decrease in agricultural emissions are explored over the country. We also investigate the changes in atmospheric NH<sub>3</sub> over an ammonia plant, which activities have been suspended due to several conflict-related events. We show that the NH<sub>3</sub> columns retrieved from IASI are directly affected by the war, and those periods of intense conflict and siege are reflected in lower NH<sub>3</sub> concentrations, which are not driven by meteorology. The interpretation of the identified changes in atmospheric NH<sub>3</sub> is supported by the analyses of NO<sub>2</sub> columns from GOME-2 as well as satellite imagery and land cover data. The latter is used to highlight the change in croplands’ area over the years, and the satellite images are used to show the activity of the ammonia plant.</p>

Nocturnal surface fluxes of N2O and CH4 determined from atmospheric measurements at the Cabauw tall tower

<p>The agricultural emissions are the dominant sources of N<sub>2</sub>O and CH<sub>4</sub> in the Netherlands. In this study, we have estimated nocturnal surface fluxes of both N<sub>2</sub>O and CH<sub>4</sub> using atmospheric measurements at the Cabauw tall tower (4.927◦ E, 51.971◦ N, - 0.7 m a.s.l.). The nocturnal N<sub>2</sub>O and CH<sub>4</sub> surface fluxes were derived using two different methods, the vertical gradient method (VGM), i.e. the sum of the storage flux and the turbulent flux, and the radon-tracer method (RTM), for the period of March 2017-December 2018 and 2016-2018, respectively. For N<sub>2</sub>O, we show that a few events occurring between May 30 and June 4 in 2018 dominated the monthly means. Using the VGM, we have estimated the annual mean nocturnal surface flux to be 0.59 ± 0.38 g/m<sup>2</sup>/yr (1 σ, the same as below) and 0.53 ± 0.19 g/m<sup>2</sup>/yr with and without events, respectively. The fluxes are high in the summer and low in the winter, with a seasonal amplitude of around 1.0 g/m2/yr and 0.5 g/m<sup>2</sup>/yr, with and without events, respectively, which is likely caused by the seasonality of agricultural activities. For CH<sub>4, </sub>the annual mean nocturnal surface flux is 12.1 ± 3.3 g/m<sup>2</sup>/yr and the amplitude is around 9.9 g/m<sup>2</sup>/yr. Using the RTM, the mean fluxes of the whole period for N<sub>2</sub>O and CH<sub>4 </sub>are estimated to be 1.18 ± 2.25 (1.08 ± 1.29, without the events) g/m<sup>2</sup>/yr and 26.9 ± 24.8 g/m<sup>2</sup>/yr, respectively; in contrast to the VGM, no apparent seasonal pattern has been found. However, there is a good linear correlation between the estimated N<sub>2</sub>O fluxes from the two methods and the monthly means show a similar pattern when the same nights are considered; the R-squared value is around 0.9 with events and 0.6 without events, and the slope varies from 1.9 to 0.8 when different estimates of radon fluxes are used. Furthermore, we found that large N<sub>2</sub>O fluxes are related to the amount of rainfall occurring days before, with the correlation coefficient of around 0.6 (p value<0.01). For CH<sub>4</sub>, there is no correlation between the estimated CH<sub>4</sub> fluxes from the two methods. Our findings demonstrate that nocturnal N<sub>2</sub>O and CH<sub>4</sub> fluxes in the Cabauw area are highly variable and vary over different seasons, and that both VGM and RTM are useful to quantify regional N<sub>2</sub>O and CH<sub>4</sub> fluxes.</p>