Greenhouse Gas Contribution Research Articles

Contribution of Greenhouse Gas Radiative Forcing and Atlantic Multidecadal Oscillation to Surface Air Temperature Trends

The contributions of radiative forcing of greenhouse gases (GHG) and Atlantic Multidecadal Oscillation (AMO) to the trends in global surface air temperature (GST) and surface air temperature for different latitude bands are estimated. Instrumental observational data obtained since the middle of the 19th century and three-component autoregressive models are used. Characteristics of influences of both factors on GST (Wiener–Granger causality) are obtained. The contribution of AMO over the length intervals of 15–30 years appears comparable in absolute value to the contribution of GHG and sometimes even exceeds it, while its contribution over 60-year and longer periods is insignificant. During the recent decades, GHG contribute stronger to the trends of GST and tropical surface air temperature, while their contribution to the trends in surface air temperature in the middle and high latitudes is smaller.

Effect of Climate Change on the Yield of Cereal Crops: A Review

By the end of this century, the average global temperature is predicted to rise due to the increasing release of greenhouse gases (GHGs) into the atmosphere. This change in climate can reduce agricultural yields, resulting in food insecurity. However, agricultural activities are one of the major contributors of GHGs and lower yields can trigger increased activity to meet the demand for food, resulting in higher quantities of GHGs released into the atmosphere. In this paper, we discuss the growth requirements and greenhouse gas release potential of staple cereal crops and assess the impact of climate change on their yields. Potential solutions for minimizing the influence of climate change on crop productivity are discussed. These include breeding to obtain cereals that are more tolerant to conditions caused by climate change, increased production of these new cultivars, improved irrigation, and more effective use of fertilizers. Furthermore, different predictive models inferred that climate change would reduce production of major cereal crops, except for millets due to their ability to grow in variable climatic conditions, and in dry areas due to a strong root system. Moreover, millets are not resource-intensive crops and release fewer greenhouse gases compared to other cereals. Therefore, in addition to addressing food security, millets have an enormous potential use for reducing the impact of agriculture on global warming and should be grown on a global scale as an alternative to major cereals and grains.

Carbon footprint and fossil energy consumption of bio-ethanol fuel production from Arundo donax L. crops on marginal lands of Southern Italy

A cradle-to-wheel life cycle analysis evaluated the greenhouse gas (GHG) contribution and fossil energy consumption (FEC) of bio-ethanol (EtOH) from dedicated crops on marginal lands in Campania Region (Southern Italy). The analysis processed experimental agronomic data of giant reed cultivated on hilly areas at high erosion risk and industrial data of feedstock conversion to EtOH, through second generation innovative technologies. Two ethanol–gasoline mixes (E10 and E85) were considered and compared with gasoline vehicle (GV).The E10 GHG and FEC profiles were driven by the gasoline input in the blend and the linked CO2 tailpipe emissions. The EtOH supply chain, especially the crop phase, was the major contributor to E85 impacts. The higher amount of biogenic C in E85 determined a marked reduction over GV of both GHG emissions (−60%) and FEC (−65%). The soil carbon storage would save 25 g CO2 eq per MJ; however, the issue is controversial due to the spatial and temporal variability of the process. Based on land availability, E85 contribution to renewables in the regional transport sector would amount to 4% and the blend wall would be far from saturation. A possible mismatch between future flexi-fuel vehicles density and E85 availability should be considered.

Detectability of the impacts of ozone-depleting substances and greenhouse gases upon stratospheric ozone accounting for nonlinearities in historical forcings

Abstract. We perform a formal attribution study of upper- and lower-stratospheric ozone changes using observations together with simulations from the Whole Atmosphere Community Climate Model. Historical model simulations were used to estimate the zonal-mean response patterns (“fingerprints”) to combined forcing by ozone-depleting substances (ODSs) and well-mixed greenhouse gases (GHGs), as well as to the individual forcing by each factor. Trends in the similarity between the searched-for fingerprints and homogenized observations of stratospheric ozone were compared to trends in pattern similarity between the fingerprints and the internally and naturally generated variability inferred from long control runs. This yields estimated signal-to-noise (S∕N) ratios for each of the three fingerprints (ODS, GHG, and ODS + GHG). In both the upper stratosphere (defined in this paper as 1 to 10 hPa) and lower stratosphere (40 to 100 hPa), the spatial fingerprints of the ODS + GHG and ODS-only patterns were consistently detectable not only during the era of maximum ozone depletion but also throughout the observational record (1984–2016). We also develop a fingerprint attribution method to account for forcings whose time evolutions are markedly nonlinear over the observational record. When the nonlinearity of the time evolution of the ODS and ODS + GHG signals is accounted for, we find that the S∕N ratios obtained with the stratospheric ODS and ODS + GHG fingerprints are enhanced relative to standard linear trend analysis. Use of the nonlinear signal detection method also reduces the detection time – the estimate of the date at which ODS and GHG impacts on ozone can be formally identified. Furthermore, by explicitly considering nonlinear signal evolution, the complete observational record can be used in the S∕N analysis, without applying piecewise linear regression and introducing arbitrary break points. The GHG-driven fingerprint of ozone changes was not statistically identifiable in either the upper- or lower-stratospheric SWOOSH data, irrespective of the signal detection method used. In the WACCM simulations of future climate change, the GHG signal is statistically identifiable between 2020 and 2030. Our findings demonstrate the importance of continued stratospheric ozone monitoring to improve estimates of the contributions of ODS and GHG forcing to global changes in stratospheric ozone.

Can an Emission Trading Scheme Really Reduce CO2 Emissions in the Short Term? Evidence from a Maritime Fleet Composition and Deployment Model

Global warming has become one of the most popular topics on this planet in the past decades, since it is the challenge that needs the efforts from the whole mankind. Maritime transportation, which carries more than 90% of the global trade, plays a critical role in the contribution of green house gases (GHGs) emission. Unfortunately, the GHGs emitted by the global fleet still falls outside the emission reduction scheme established by the Kyoto Protocol. Alternative solutions are therefore strongly desired. Several market-based measures are proposed and submitted to IMO for discussion and evaluation. In this paper, we choose to focus on one of these measures, namely Maritime Emissions Trading Scheme (METS). An optimization model integrating the classical fleet composition and deployment problem with the application of ETS (global or regional) is proposed. This model is used as a tool to study the actual impact of METS on fleet operation and corresponding CO2 emission. The results of the computational study suggest that in the short term the implementation of METS may not guarantee further emission reduction in certain scenarios. However, in other scenarios with low bunker price, high allowance cost or global METS coverage, a more significant CO2 decrease in the short term can be expected.

Slippery Violence in the REDD+ Forests of Central Kalimantan, Indonesia

Due to increasing global demand for palm oil, coal, and timber, Indonesia has become the largest contributor of greenhouse gases from primary forest loss in the world. Carbon market mechanisms, like Reducing Emissions from Deforestation and forest Degradation (REDD+), are being promoted by many elements of Indonesia's government as an effective policy response. The REDD+ programme is designed to enable the provision of financial compensations to protect and restore standing forests by making them more valuable than the timber they contain. However, the logic of REDD+ constructs people living in and around project sites as environmentally destructive and therefore in need of incentivisation to do otherwise. Local people are compensated for the 'opportunity costs' of not degrading forests. Within this frame ‘locals’—suffering from the malaise of dispossession—are Othered as illegal loggers, poachers, greedy miners or arsonists. In reality, REDD+ often facilitates the continuation of violence, legitimising an image of small-holders, rather than large international corporations, as the cause of forest degradation in Indonesia. Focusing on the Sungai Lamandau REDD+ project of Central Kalimantan, I discuss how, for some of Sungai Lamandau's landless farmers, REDD+ is accelerating the very violence and environmentally destructive behaviours it claims to discourage. Farmers are becoming embroiled in other ongoing processes, pushing them towards illicit livelihood strategies, sometimes with devastating outcomes.

In vitro assessment of ruminal fermentation, digestibility and methane production of three species of Desmanthus for application in northern Australian grazing systems

Three species of Desmanthus adapted to the heavy clay soils of northern Australia were studied to determine their nutritive value and effects on in vitro fermentation with rumen fluid, compared with Rhodes grass (Chloris gayana) hay. Leaves and stems of D. leptophyllus cv. JCU 1, D. virgatus cv. JCU 2 and D. bicornutus cv. JCU 4 were collected in summer, winter and spring of 2014 and analysed for chemical composition. Apparent digestibility as in vitro organic matter digestibility (IVD-OM) and fermentation parameters including methane (CH4) production were measured during 72-h fermentations using rumen fluid from steer donors grazing tropical grasses and legumes. Desmanthus bicornutus was on average more digestible than both D. leptophyllus and D. virgatus at 24, 48 and 72 h of incubation. This species also demonstrated an anti-methanogenic potential, in particular when harvested in summer with a reduction in CH4 production of 26% compared with Rhodes grass hay after 72 h of incubation. At this time point, D. leptophyllus produced higher volatile fatty acids (VFA per g of organic matter fermented) compared with the other forages. This legume also reduced the CH4 production up to 36% compared with the Rhodes grass hay reference. However, D. leptophyllus showed lower IVD-OM. Overall, Desmanthus species produced lower in vitro CH4 and lower volatile fatty acids concentration compared with the reference grass hay. These effects may be due to presence of secondary compounds such as hydrolysable tannins, condensed tannins and/or their combination in Desmanthus species. The IVD-OM was influenced by the season after 72 h of incubation; the digestibility was higher in plants collected in spring. This study suggests that contrasting fermentative profiles in Desmanthus cultivars may offer the opportunity to reduce the greenhouse gas contribution of the beef industry. The next step in demonstration of these promising in vitro results is demonstration of Desmanthus in vivo as proof of concept confirming the productivity and CH4 reduction ability of these legumes in the pastoral systems of northern Australia.

Greenhouse gas contribution of municipal solid waste collection: A case study in the city of Istanbul, Turkey.

This article estimates greenhouse gas emissions and global warming factors resulting from collection of municipal solid waste to the transfer stations or landfills in Istanbul for the year of 2015. The aim of this study is to quantify and compare diesel fuel consumption and estimate the greenhouse gas emissions and global warming factors associated with municipal solid waste collection of the 39 districts of Istanbul. Each district's greenhouse gas emissions resulting from the provision and combustion of diesel fuel was estimated by considering the number of collection trips and distances to municipal solid waste facilities. The estimated greenhouse gases and global warming factors for the districts varied from 61.2 to 2759.1 t CO2-eq and from 4.60 to 15.20 kg CO2-eq t-1, respectively. The total greenhouse gas emission was estimated as 46.4E3 t CO2-eq. Lastly, the collection data from the districts was used to parameterise a collection model that can be used to estimate fuel consumption associated with municipal solid waste collection. This mechanistic model can then be used to predict future fuel consumption and greenhouse gas emissions associated with municipal solid waste collection based on projected population, waste generation, and distance to transfer stations and landfills. The greenhouse gas emissions can be reduced by decreasing the trip numbers and trip distances, building more transfer stations around the city, and making sure that the collection trucks are full in each trip.

The beef with sustainability.

The US beef industry is a major contributor of greenhouse gases and is commonly regarded as unsustainable at current levels. A new study models a system in which sustainability could be increased by subsistence on grass and agricultural by-products, prompting the question, ‘what are the limits of sustainable livestock production in the US’?

Assessing carbon footprints of cities under limited information

City carbon footprints have become an important tool for monitoring the progress of cities towards lowering their greenhouse gas emissions and contribution to climate change. Cities usually source a major part of their natural resource demand from their local, national and global hinterland, and cause emissions across the whole global supply chain of a city's final demand. It is important that the data underlying carbon footprint assessments of cities capture these supply chains adequately and comprehensively. In this research, we determine the carbon footprints of four Chinese cities, Beijing, Shanghai, Chongqing and Tianjin based on different levels of data availability. Using these case studies, we show conclusively that city carbon footprint analyses must include input-output databases and associated calculus in order to avoid severe errors that arise from unacceptable scope limitations caused by the truncation of the footprint assessment boundary. We also show that city input-output databases must fulfil a number of requirements for city comparisons and for informed decision-making to be feasible. Our findings suggest that investment into multi-layered national input-output tables and datasets will be necessary to monitor progress of cities reducing their greenhouse emissions across the whole supply chain and to inform evidence based policy making that guides greenhouse abatement.

Estimating Potential Methane Emission from Municipal Solid Waste and a Site Suitability Analysis of Existing Landfills in Delhi, India

The management of rapidly growing municipal solid waste (MSW) is one of the major challenges in developing countries. The current study also estimates the suitability of a site through a geographical information system using multi-criteria decision analysis (MCDA) for landfill sites in National Capital Territory (NCT). The results of the suitability index indicate that only 58.7 km2 of the land is suitable for the construction of landfill sites, while 194.27 km2 of the total area is moderately suitable. The existing three landfill sites that are currently functional and used by government organizations as landfills are found to be moderately suitable. A large fraction of MSW is disposed in landfills, which emit one third of the total anthropogenic methane (CH4) and are considered an important contributor of Green House Gases (GHGs) to the atmosphere. Thus, there is a need for the proper estimation of GHG emission from landfills, specifically CH4, which contributes 20% of the GHGs that contribute to global warming. The current study aims to estimate the CH4 emission from landfills in the NCT, Delhi, India using GHG inventory guidelines from the Intergovernmental Panel on Climate Change (IPCC). The CH4 emission from landfills has doubled from 31.06 Gg/yr to 65.16 Gg/yr from 1999 and 2000 to 2015. The generation of CH4 from MSW is strongly correlated (R2 = 0.58) with the Gross State Domestic Product (GSDP), which is an indicator of wellbeing.

Contribution of urbanization to the increase of extreme heat events in an urban agglomeration in east China

AbstractThe urban agglomeration of Yangtze River Delta (YRD) is emblematic of China's rapid urbanization during the past decades. Based on homogenized daily maximum and minimum temperature data, the contributions of urbanization to trends of summer extreme temperature indices (ETIs) in YRD are evaluated. Dynamically classifying the observational stations into urban and rural, this study presents unexplored changes in temperature extremes during the past four decades in YRD and quantifies the amplification of the positive trends in ETIs by the urban heat island effect. Overall, urbanization contributes to more than one third of the increase of intensity of extreme heat events in the region, which is comparable to the contribution of greenhouse gases. Compared to rural stations, more notable shifts to the right in the probability distribution of temperature and ETIs are found in urban stations. The rapid urbanization in YRD has resulted in large increases in the risk of heat extremes.

Assessing energy efficiencies, economy, and global warming potential (GWP) effects of major crop production systems in Iran: a case study in East Azerbaijan province.

Efficient use of energy in farming systems is one of the most important implications for decreasing greenhouse gas (GHG) emissions and mitigating global warming (GW). This paper describes the energy use patterns, analyze the economics, and report global warming potential effects of major crop production systems in East Azerbaijan province, Iran. For this purpose, 110 farmers whose main activity was major crop production in the region, including wheat, barley, carrot, tomato, onion, potato, alfalfa, corn silage, canola, and saffron, were surveyed. Some other data was obtained from the Ministry of Agriculture Jihad of Iran. Results showed that, in terms of total energy input, onion (87,556 Mj ha-1) and potato (80,869 Mj ha-1) production systems were more energy-intensive than other crops. Among the studied crops, the highest values of net return (6563.8 $ ha-1) and benefit/cost ratio (1.95) were related to carrot and corn silage production systems, respectively. Studies have also shown that onion and saffron production systems emit the highest (5332.6kg CO2eq ha-1) and lowest (646.24kg CO2eq ha-1) CO2 eq. emission, respectively. When it was averaged across crops, diesel fuel accounted for the greatest GHG contribution with 43% of the total, followed by electric power (28%) and nitrogen fertilizer (21%). In the present study, eco-efficiency was calculated as a ratio of the gross production value and global warming potential effect for the studied crops. Out of all the studied crops, the highest values of eco-efficiency were calculated to be 8.65 $ kg CO2eq-1 for the saffron production system followed by the carrot (3.65 $ kg CO2eq-1) production. Generally, from the aspect of energy balance and use efficiency, the alfalfa production system was the best; however, from an economical point of view, the carrot production system was better than the other crops.

Carbon Stocks on Forest Stewardship Program and Adjacent Lands

Nonindustrial private forestlands in Florida provide many environmental benefits, or ecosystem services. Ecosystem services are benefits from nature that are directly enjoyed, consumed, or used by humans, such as water quality improvement or protection, recreation, biodiversity, and even timber. Another benefit from forests that is gaining interest is their ability to store carbon through the photosynthetic capture of carbon dioxide, a greenhouse gas, in tree, plant, and soil biomass. The carbon dioxide that is stored over the life of a forest, called carbon stocks, is not only important for mitigating greenhouse gas contributions to climate change, but it can also be valued in several markets and incorporated into environmental policy instruments. This 5-page fact sheet was written by Nilesh Timilsina, Francisco J. Escobedo, Alison E. Adams, and Damian C. Adams and published by the UF Department of School of Forest Resources and Conservation April 2017.­
 Original publication date October 2013; revised March2017. Archived 9/18/2020.

Estimation and comparison of environmental emissions and impacts at foundation and structure construction stages of a building – A case study

Previous studies have seldom investigated the effects of direct emissions at different stages of a building construction. This study aims to estimate and compare direct and indirect emissions and environmental impacts at foundation and structure construction stages of a building using a case study. The case study is multi-storey commercial building construction with concrete framing. A process based methodology is developed to estimate emissions from seven sources that contribute to both greenhouse gas (GHG) and non-GHG emissions. An impact assessment is also carried out to compare the environmental impacts for different stages of construction from global, regional and local perspectives. The results highlight an overpowering indirect GHG contribution of 89% from material embodied emissions at the structure construction stage. Direct GHG emissions at the foundation construction are prominent with a contribution of 12.7% and 13.4% for emissions from equipment usage and transportation respectively. Nitrous Oxides (NOx) and Carbon Monoxides (CO) are recorded as the most prominent non-GHG emissions. The results were further analysed based on four scenarios corresponding to direct and indirect emissions. The results signified a GHG emission reduction of 12% can be achieved by adopting sustainable materials such as fly ash and blast furnace concrete. The impact assessment results illustrate a large contribution to global warming potential (GWP) with a value of over 98% for the construction stage from the global perspective. This large contribution from GWP is reduced to 60% and 57% with relative high contributions from Photochemical Oxidation Potential (POFP) with 26% and 34% at regional and local levels. The scenario analyses on direct emissions highlight the importance of resource utilisation in reducing impacts at local level. The results indicate that identification of the significant emission sources and impact categories at different construction stages, prior to implementing emission reduction opportunities such as usage of sustainable materials and operational optimisation of construction equipment and transportation vehicles is key to minimising impacts at building construction.

Intimate Exclusions from the REDD+ forests of Sungai Lamandau, Indonesia

Due to land-use conversions for palm oil, mining and other extractive industries, Indonesia remains the largest contributor of greenhouse gases from primary forest loss in the world. Nowhere are solutions to large-scale forest loss more urgently required. To reverse the trend, the Government of Indonesia is banking on carbon market mechanisms like the Reducing Emissions from Deforestation and Degradation (REDD+) programme. REDD+ is designed to enable the provision of economic compensations to protect forests by making them more valuable standing than cut down. The Sungai Lamandau REDD+ demonstration activity is unique in Indonesia as the first REDD+ project officially proposed by a community group upon land they hope to manage autonomously. Despite the project's 'bottom-up' architecture, for some, access to Sungai Lamandau's REDD+ benefits remain exclusive. These exclusions are not only something imposed by powerful external actors, but has emerged endogenously, through the everyday functioning of gendered market relations, and community-based socio-environmental and ethno-territorial movements. This paper adopts a feminist-inspired intimacy-geopolitics to explore the nuanced powers of exclusion used by Sungai Lamandau's farmers to access the project's non-monetary REDD+ benefits. The paper focuses on 'intimate exclusions' – everyday processes of accumulation and dispossession among villagers and small-holders. In doing so, it highlights the hazards of developing REDD+ projects structured with limited sympathy for marginalised actors. Although the seemingly 'inclusive' benefits sharing structure attracted excellent ethical carbon credit ratings, the project still failed to address (and even exacerbated) existing inequalities – a root cause of Sungai Lamandau's forest degradation.

Nutrient Cycling in Grassed Roadside Ditches and Lawns in a Suburban Watershed.

Roadside ditches are ubiquitous in developed landscapes. They are designed to route water from roads for safety, with little consideration of water quality or biogeochemical implications in ditch design and minimal data on environmental impacts. We hypothesize that periodic saturation and nutrient influxes may make roadside ditches hotspots for nitrogen (N) removal via denitrification as well as biological production of the greenhouse gases (GHGs) nitrous oxide (NO), methane (CH), and carbon dioxide (CO). Research sites included 12 grassed ditches and adjacent lawns with varying fertilization in a suburban watershed in central New York, where lawns represented a reference with similar soils as ditches but differing hydrology. We measured potential denitrification using the denitrification enzyme assay in fall 2014 and GHG fluxes using in situ static chambers between summer 2014 and 2015, including sample events after storms. Potential denitrification in ditches was significantly higher than in lawns, and rates were comparable to those in stream riparian areas, features traditionally viewed as denitrification hotspots. Ditches had higher rates of CH emissions, particularly sites that were wettest. Lawns were hotspots for NO and CO respiratory emissions, which were driven by nutrient availability and fertilizer application. Extrapolating up to the watershed, ditches have the potential to remove substantial N loads via denitrification if managed optimally. Ditch GHG emissions extrapolated across the watershed were minimal given their much smaller area compared with lawns, which were the greater contributor of GHGs. These findings suggest that roadside ditches may offer new management opportunities for mitigating nonpoint source N pollution in residential watersheds.

Climate Change and International Trade Law: A South African Perspective

International trade is a major contributor to greenhouse gas (GHG) emissions. Increasing GHG concentrations in the atmosphere ‘cause the sun’s heat (which would otherwise be radiated back into space) to be retained in the earth’s atmosphere, thereby contributing to the greenhouse effect that causes global warming and climate change’. In turn, the physical processes associated with climate change – increasing temperature and changes in precipitation, sea level rise and increasing frequency and intensity of extreme weather events – and the adoption of certain climate change response measures by South Africa’s major trading partners, the European Union (EU), China, the United States (US), the Kingdom of Saudi Arabia, Japan and India, are likely to affect South Africa’s trading capacity. The linkages between international trade and climate change, either negative or positive, therefore, are relevant in respect of both mitigation and adaptation. In this chapter I examine some of South Africa’s response measures to mitigate, more precisely to reduce its GHG emissions attributable to trade, as well as to adapt to the consequences of climate change for its trading capacity (part 4). For this purpose I begin with demonstrating how international trade contributes to South Africa’s GHG emissions and how, in turn, the physical processes associated with climate change are likely to impact on South Africa’s trading capacity (part 1). I then continue with explaining the context, i.e. the linkages between international trade and climate change (part 2) in order to illustrate how the various climate change response measures adopted by South Africa’s major trading partners are also likely to affect its trading capacity (part 3).

Emission Taxes and Product Differentiation in the Presence of Foreign Firms

Industries characterized by differentiated products are important contributors of greenhouse gases and currently subject to market-based policies such as emission taxes. In the context of developing countries, fears about foreign investment leaving the country are often used as an argument not to address industry emissions through emission taxes. This paper develops a Cournot model with product differentiation in the presence of abatement efforts where host and foreign firms are subject to an emission tax. The analysis indicates that abatement efforts and differences in pollution intensity coefficients across firms may play a significant role in the characterization of optimal policy. The analysis also suggests that the government may opt to encourage foreign, less pollution-intensive firms via higher taxation. Additionally, this paper examines how an optimal emission tax may be adjusted as products become more differentiated; industry emissions may fall/rise as a result of more differentiated products. One important contribution of this paper is that it emphasizes the role of abatement efforts, product differentiation, and differences in pollution intensity coefficients across firms in the characterization of the optimal emission tax.

Climate Change Mitigation and the Collective Action Problem: Exploring Country Differences in Greenhouse Gas Contributions

Global climate change has become the collective action problem of our era. With the United Nations Framework Convention on Climate Change (UNFCCC) 2015 COP21 Meetings in Paris as the context, the author draws upon critical mass theory (CMT) (Oliver and Marwell 1988; Oliver, Marwell, and Teixeria 1985) in an attempt to yield greater understanding of the international community's ability to achieve climate stability as a global public good. Using CMT key elements of collective action production functions, group heterogeneity, and interdependence, the author explores the world's collective ability to mitigate greenhouse gas (GHG) emissions at the country level. Brief examples from Belize, Central America, and other small, vulnerable nations are used to focus attention on those countries that cannot make meaningful contribution to the collection action. The findings help illustrate why climate change is such a difficult collective action problem to address, what broad strategies might be required, and how to potentially achieve more targeted distribution of international resources.