Agricultural subsidies and global greenhouse gas emissions

Abstract. To track progress towards keeping global warming well below 2 ∘C or even 1.5 ∘C, as agreed in the Paris Agreement, comprehensive up-to-date and reliable information on anthropogenic emissions and removals of greenhouse gas (GHG) emissions is required. Here we compile a new synthetic dataset on anthropogenic GHG emissions for 1970–2018 with a fast-track extension to 2019. Our dataset is global in coverage and includes CO2 emissions, CH4 emissions, N2O emissions, as well as those from fluorinated gases (F-gases: HFCs, PFCs, SF6, NF3) and provides country and sector details. We build this dataset from the version 6 release of the Emissions Database for Global Atmospheric Research (EDGAR v6) and three bookkeeping models for CO2 emissions from land use, land-use change, and forestry (LULUCF). We assess the uncertainties of global greenhouse gases at the 90 % confidence interval (5th–95th percentile range) by combining statistical analysis and comparisons of global emissions inventories and top-down atmospheric measurements with an expert judgement informed by the relevant scientific literature. We identify important data gaps for F-gas emissions. The agreement between our bottom-up inventory estimates and top-down atmospheric-based emissions estimates is relatively close for some F-gas species (∼ 10 % or less), but estimates can differ by an order of magnitude or more for others. Our aggregated F-gas estimate is about 10 % lower than top-down estimates in recent years. However, emissions from excluded F-gas species such as chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs) are cumulatively larger than the sum of the reported species. Using global warming potential values with a 100-year time horizon from the Sixth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC), global GHG emissions in 2018 amounted to 58 ± 6.1 GtCO2 eq. consisting of CO2 from fossil fuel combustion and industry (FFI) 38 ± 3.0 GtCO2, CO2-LULUCF 5.7 ± 4.0 GtCO2, CH4 10 ± 3.1 GtCO2 eq., N2O 2.6 ± 1.6 GtCO2 eq., and F-gases 1.3 ± 0.40 GtCO2 eq. Initial estimates suggest further growth of 1.3 GtCO2 eq. in GHG emissions to reach 59 ± 6.6 GtCO2 eq. by 2019. Our analysis of global trends in anthropogenic GHG emissions over the past 5 decades (1970–2018) highlights a pattern of varied but sustained emissions growth. There is high confidence that global anthropogenic GHG emissions have increased every decade, and emissions growth has been persistent across the different (groups of) gases. There is also high confidence that global anthropogenic GHG emissions levels were higher in 2009–2018 than in any previous decade and that GHG emissions levels grew throughout the most recent decade. While the average annual GHG emissions growth rate slowed between 2009 and 2018 (1.2 % yr−1) compared to 2000–2009 (2.4 % yr−1), the absolute increase in average annual GHG emissions by decade was never larger than between 2000–2009 and 2009–2018. Our analysis further reveals that there are no global sectors that show sustained reductions in GHG emissions. There are a number of countries that have reduced GHG emissions over the past decade, but these reductions are comparatively modest and outgrown by much larger emissions growth in some developing countries such as China, India, and Indonesia. There is a need to further develop independent, robust, and timely emissions estimates across all gases. As such, tracking progress in climate policy requires substantial investments in independent GHG emissions accounting and monitoring as well as in national and international statistical infrastructures. The data associated with this article (Minx et al., 2021) can be found at https://doi.org/10.5281/zenodo.5566761.

Modelling food demand in the 21st century

Transportation has emerged as a major contributor to greenhouse gas (GHG) emissions worldwide. With increasing population growth and food demand, the spatial decoupling of production and consumption has intensified, driving a surge in transnational agricultural products transportation. However, existing research lacks a systematic assessment and future projection of GHG emissions from agricultural product transportation across multiple transport modes worldwide. To address this gap, we developed a global trade-linked transport GHG emission database by integrating multisource data and modeling frameworks. Compared with the research method in this paper, the previous great circle distance as the GHG emission of agricultural product transportation mileage was underestimated by 34%. This study systematically evaluates the spatiotemporal evolution of agricultural transport GHG emissions from 2000 to 2021 and explores their mitigation potential under future scenarios. Our findings reveal that global GHG emissions from agricultural transport increased by 1.6-fold over the 21-year period, with rising GHG emission intensity and trade density collectively shaping a high-carbon flow pattern dominated by exports from the Americas to Asia. Future scenario analyses indicate that the localization strategies proposed in this study are not particularly effective in reducing transport-related GHG emissions as inefficiencies inherent in localized agricultural production can increase production-stage emissions and, in turn, result in a net rise in total GHG outputs. These results suggest that future strategies should prioritize optimizing trade structures while simultaneously enhancing domestic agricultural productivity and promoting low-carbon farming technologies to achieve net emission reductions at the source.

Major US electric utility climate pledges have the potential to collectively reduce power sector emissions by one-third

Anthropogenic activities have altered approximately two-thirds of the Earth's land surface. Urbanization, industrialization, agricultural expansion, and deforestation are increasingly impacting the terrestrial landscapes, leading to shifts of areas in artificial surface (i.e., humanmade), cropland, pasture, forest, and barren land. Land use patterns and associated greenhouse gas (GHG) emissions play a critical role in global climate change. Here we synthesized 29 years of global historical data and demonstrated how land use impacts global GHG emissions using structural equation modeling. We then obtained predictive estimates of future global GHG emissions using a deep learning model. Our results show that, from 1992 to 2020, the global terrestrial areas covered by artificial surface and cropland have expanded by 133% and 6% because of population growth and socioeconomic development, resulting in 4.0% and 3.8% of declines in pasture and forest areas, respectively. Land use was significantly associated with GHG emissions (p < 0.05). Artificial surface dominates global GHG emissions, followed by cropland, pasture, and barren land. The increase in artificial surfaces has driven up global GHG emissions through the increase in energy consumption. Conversely, improved agricultural management practices have contributed to mitigating agricultural GHG emissions. Forest, on the other hand, serves as a sink of GHG. In total, global GHG emissions increased from 31 to 46 GtCO2eq from 1992 to 2020. Looking ahead, if current trends in global land use continue at the same rates, our model projects that global GHG emissions will reach 76 ± 8 GtCO2eq in 2050. In contrast, reducing the rates of land use change by half could limit global GHG emissions to 60 ± 3 GtCO2eq in 2050. Monitoring and analyzing these projections allow a better understanding of the potential impacts of various land use scenarios on global climate and planning for a sustainable future.

Japan depends heavily on imports for its food supply. Since 2000, the food self‐sufficiency ratio has remained approximately 40% on a caloric basis. Japanese food wastage (i.e., food losses and food waste) is estimated to have been 6.42 million tonnes (50 kg per capita of wastage) in 2012. These values indicate that food wastage leads to wasted natural resources and excessive greenhouse gas (GHG) emissions both in Japan and in countries that export to Japan. This study estimates Japanese food wastage by food item to evaluate impacts on land and water resources and global GHG emissions during the processing, distribution, and consumption phases of the food supply chain while also considering the feed crops needed for livestock production. Despite uncertainties due to data limitations, in 2012, 1.23 million hectares of harvested land were used to produce food that was eventually wasted, and 413 million m3 of water resources were wasted due to Japanese food wastage in agricultural production. Furthermore, unnecessary GHG emissions were 3.51 million tonnes of CO2 eq. in agricultural production and 0.49 million tonnes of CO2 eq. in international transportation. The outcomes of the present study can be used to develop countermeasures to food wastage in industrializing Asian countries where food imports are projected to increase and food wastage issues in the consumption stage are expected to become as serious as they currently are in Japan.

Livestock and greenhouse gas emissions: The importance of getting the numbers right

Advanced wastewater treatment processes and novel technologies are adopted to improve nutrient removal from wastewater so as to meet stringent discharge standards. Municipal wastewater treatment plants are one of the major contributors to the increase in the global greenhouse gas (GHG) emissions and therefore it is necessary to carry out intensive studies on quantification, assessment and characterization of GHG emissions in wastewater treatment plants, on the life cycle assessment from GHG emission prospective, and on the GHG mitigation strategies. Greenhouse Gas Emission and Mitigation in Municipal Wastewater Treatment Plants summarises the recent development in studies of greenhouse gases’ (CH4 and N2O) generation and emission in municipal wastewater treatment plants. It introduces the concepts of direct emission and indirect emission, and the mechanisms of GHG generations in wastewater treatment plants’ processing units. The book explicitly describes the techniques used to quantify direct GHG emissions in wastewater treatment plants and the protocol used by the Intergovernmental Panel on Climate Change (IPCC) to estimate GHG emission due to wastewater treatment in the national GHG inventory. Finally, the book explains the life cycle assessment (LCA) methodology on GHG emissions in consideration of the energy and chemical usage in municipal wastewater treatment plants. In addition, the strategies to mitigate GHG emissions are discussed. The book provides an overview for researchers, students, water professionals and policy makers on GHG emission and mitigation in municipal wastewater treatment plants and industrial wastewater treatment processes. It is a valuable resource for undergraduate and postgraduate students in the water, climate, and energy areas; for researchers in the relevant areas; and for professional reference by water professionals, government policy makers, and research institutes. ISBN: 9781780406305 (Print) ISBN: 9781780406312 (eBook) ISBN: 9781780409054 (ePUB)

Contributions of natural systems and human activity to greenhouse gas emissions

BackgroundSocietal pressures exist to reduce greenhouse gas (GHG) emissions from farm animals, especially in beef cattle. Both total GHG and GHG emissions per unit of product decrease as productivity increases. Limitations of previous studies on GHG emissions are that they generally describe feed intake inadequately, assess the consequences of selection on particular traits only, or examine consequences for only part of the production chain. Here, we examine GHG emissions for the whole production chain, with the estimated cost of carbon included as an extra cost on traits in the breeding objective of the production system.MethodsWe examined an example beef production system where economic merit was measured from weaning to slaughter. The estimated cost of the carbon dioxide equivalent (CO2-e) associated with feed intake change is included in the economic values calculated for the breeding objective traits and comes in addition to the cost of the feed associated with trait change. GHG emission effects on the production system are accumulated over the breeding objective traits, and the reduction in GHG emissions is evaluated, for different carbon prices, both for the individual animal and the production system.ResultsMultiple-trait selection in beef cattle can reduce total GHG and GHG emissions per unit of product while increasing economic performance if the cost of feed in the breeding objective is high. When carbon price was $10, $20, $30 and $40/ton CO2-e, selection decreased total GHG emissions by 1.1, 1.6, 2.1 and 2.6% per generation, respectively. When the cost of feed for the breeding objective was low, selection reduced total GHG emissions only if carbon price was high (~ $80/ton CO2-e). Ignoring the costs of GHG emissions when feed cost was low substantially increased emissions (e.g. 4.4% per generation or ~ 8.8% in 10 years).ConclusionsThe ability to reduce GHG emissions in beef cattle depends on the cost of feed in the breeding objective of the production system. Multiple-trait selection will reduce emissions, while improving economic performance, if the cost of feed in the breeding objective is high. If it is low, greater growth will be favoured, leading to an increase in GHG emissions that may be undesirable.

The agricultural sector is the second most emitting sector globally, contributing about 18% of total global greenhouse gas (GHG) emissions. Multipurpose high in-demand commodities like palm oil contribute significantly to these emissions. The Roundtable on Sustainable Palm Oil (RSPO) with an objective to make the palm oil sector sustainable, developed a new tool to quantify carbon emissions from palm oil mills. The PalmGHG tool has been used in Southeast Asia to measure carbon emissions from palm oil production and for palm oil certification. However, no studies have used the tool to evaluate GHG emissions from palm oil mills in sub-Saharan Africa, which contributes about 24% of global palm oil production and is home to one of the last remaining primary forests in the world. In this study, we quantify GHG emissions along the crude palm oil (CPO) life cycle in a growing palm oil producing region in Cameroon. We use the RSPO PalmGHG accounting tool, to identify sources of CO2 emissions and quantify them in tons of CO2 equivalent. Six mills across the South West and Center regions of Cameroon were sampled. We found that the sources of carbon emissions from our sampled mills in decreasing order of magnitude are land conversion (78%), palm oil mill effluent (21%), fertilizer use (0.9%), mill fuel combustion (0.1%) and grid electricity utilization (0.04%). The average GHG emissions per ton of crude palm oil produced were exceptionally high at 22.3 tCO2e compared to other palm oil producing regions in the world such as Indonesia with only 1.6 tCO2e/ton of CPO. In addition, we found that planting oil palm on previously logged land instead of primary forest conversion could prevent field emissions by up to about 89% and by up to about 69% for replanting old oil palm stands. Intensification measures like improving palm oil mill extraction rates and improving yields would drastically reduce emissions per ton of crude palm oil produced. Although land conversion associated with deforestation remains the major source of palm oil GHG emissions, farm and mill practices such as reduction in fertilizer use, biogas capture and use of clean energy could help reduce emissions in the long run.

Carbon footprints in pork production and consumption in China from 2005 to 2020

The Russian invasion of Ukraine has the potential to exacerbate food insecurity around the world, as both countries are major exporters of grains and other agricultural products. In this model-based scenario study, medium-term effects of the war are quantified on agricultural production, trade flows, market prices, food security, land use, and greenhouse gas emissions. The scenarios assess the possible consequences of macro-economic and agricultural production impacts in Ukraine, trade sanctions against Russia, and conflict-related energy price developments for global trade, food security, and greenhouse gas emissions. From a food security perspective, we conclude that there is enough food on the global level, but higher food and energy prices cause problems for low-income populations, spending a large part of their income on staple foods. Agricultural production and area expansion in parts of the world other than Ukraine and Russia could pose a risk to biodiversity and lead to higher greenhouse gas emissions related to land. However, total greenhouse gas emissions might decrease as lower emissions from less use of fossil energy due to higher energy and fertilizer prices in the whole economy dominate additional emissions resulting from land use change.

Reducing supply chain costs is a primary concern of every organization. Organizations have implemented offshore outsourcing as an effective strategy towards reducing supply chain costs. However, neither government nor corporate organizations have sufficiently taken into account the effects of this strategy on global greenhouse gas (GHG) emissions. The purpose of this research is to analyze the impact of offshore outsourcing on global GHG emissions, and the effect of changes in fuel prices in addition to a carbon price on additional emissions on supply chain costs. The purpose is supported by five key objectives. The objectives are addressed through a systematic methodology. The analysis is supported by a literature review, and the development and testing of mathematical models. Finally, a framework to reduce global GHG emissions through a carbon price on differential emissions from manufacturing and additional emissions from international transportation is proposed. The findings suggest that offshore outsourcing has increased global emissions. The fuel prices are increasing at a rate higher than the overall rate. A carbon price on excess emissions due to outsourcing coupled with increasing fuel prices impacts supply chain costs adversely and leads to bigger lot-sizes. As an illustration at the national level, the framework showed that emissions for the USA increased by about 20% for every year between 2007 and 2010. As another example from a corporate organization, the net profit (profit after tax) for Wal-Mart was reduced by about 19% for 2006 due to a carbon price on manufacturing emissions alone. The suggested framework is a major contribution for quantifying the extent of changes in the emissions due to offshore outsourcing and the value of these emissions at a prevailing rate of carbon tax in North America. It is intended to provide a basis for reducing emissions and costs from global supply chains. The proposed framework provides a level playing field to manufacturers in different countries using different technologies, provides incentives to organizations for manufacturing in locations where net emissions are low, helps national governments determine how they can generate revenue for dealing with emissions, and, most importantly, aids in reducing overall global GHG emissions.

Reducing supply chain costs is a primary concern of every organization. Organizations have implemented offshore outsourcing as an effective strategy towards reducing supply chain costs. However, neither government nor corporate organizations have sufficiently taken into account the effects of this strategy on global greenhouse gas (GHG) emissions. The purpose of this research is to analyze the impact of offshore outsourcing on global GHG emissions, and the effect of changes in fuel prices in addition to a carbon price on additional emissions on supply chain costs. The purpose is supported by five key objectives. The objectives are addressed through a systematic methodology. The analysis is supported by a literature review, and the development and testing of mathematical models. Finally, a framework to reduce global GHG emissions through a carbon price on differential emissions from manufacturing and additional emissions from international transportation is proposed. The findings suggest that offshore outsourcing has increased global emissions. The fuel prices are increasing at a rate higher than the overall rate. A carbon price on excess emissions due to outsourcing coupled with increasing fuel prices impacts supply chain costs adversely and leads to bigger lot-sizes. As an illustration at the national level, the framework showed that emissions for the USA increased by about 20% for every year between 2007 and 2010. As another example from a corporate organization, the net profit (profit after tax) for Wal-Mart was reduced by about 19% for 2006 due to a carbon price on manufacturing emissions alone. The suggested framework is a major contribution for quantifying the extent of changes in the emissions due to offshore outsourcing and the value of these emissions at a prevailing rate of carbon tax in North America. It is intended to provide a basis for reducing emissions and costs from global supply chains. The proposed framework provides a level playing field to manufacturers in different countries using different technologies, provides incentives to organizations for manufacturing in locations where net emissions are low, helps national governments determine how they can generate revenue for dealing with emissions, and, most importantly, aids in reducing overall global GHG emissions.