Global Warming Potential Impact Research Articles

Life Cycle Carbon Assessment of Mortars with Carbonated and Non-Carbonated Recycled Aggregates

Global warming is one of the most important issues that the world is currently facing. The cement industry accounts for around 7% of total global CO2 emissions. According to the 13th United Nations Sustainable Development Goals, cement plants must become carbon neutral by 2050. This neutrality may be achieved by a reduction in CO2 emissions complemented with carbon capture, utilization and storage (CCUS) technologies. In accordance with these sustainable goals, several approaches have been studied. This paper investigates life cycle carbon of mortars produced with carbonated recycled aggregates. In previous works, the carbon dioxide capture capacity of construction and demolition waste (CDW) was analysed, and mortars with CDW recycled aggregates submitted to high levels of CO2 were evaluated in terms of their mechanical performance. This paper focus on the life cycle carbon impact assessment (LCCA) of industrial mortar formulations in a cradle-to-gate boundary. This assessment is carried out through a global warming potential environment impact assessment, since it represents the amount of CO2 equivalent that is sent to the atmosphere and contributes to the “greenhouse effect”. This LCCA includes the impacts associated with the treatment and additional transportation routes of the recycled aggregates. With this work, it was found that mortars with carbonated recycled aggregates have a considerably lower global warming potential impact than mortars without recycled aggregates. The mortars with recycled aggregates presented lower CO2 emissions of up to 6.31% for 100% incorporation of non-carbonated recycled aggregates. These values were incremented with the carbonation of the recycled aggregates, achieving a reduction of CO2 emissions of up to 36.75% for 100% of incorporation.

How methods to assess land-use changes influence the resulting global warming potential and cost of optimized diets: a case study on Danish pigs applying life cycle assessment methodology

PurposeMeeting the demands of a growing and increasingly affluent population necessitates a deeper understanding of the environmental and economic implications of production. This implication is most relevant in key production sectors including agriculture and livestock. This article is intended to provide an understanding of the influence of methods of assessing land-use change (LUC) with respect to minimizing both the global warming potential (GWP) and the monetary costs of pig feed formulation.MethodsFeed mixtures intended for slaughter pigs were generated for minimal cost and GWP impacts by applying four differing LUC assessment methods. The objective function was the Danish slaughter pig feed unit, minimized for cost in Danish crowns (DKK), with GWP impacts constrained in multiple steps. Attributional LCA methodology was applied using the Agri-footprint 6.3 database, with GWP impacts calculated excluding land use changes, including direct land-use changes and including the carbon opportunity cost. Analyses of the functional relationship between the optimal cost and the GWP impact were conducted, followed by a comparative LCA of the cost of comparable feed mixture by applying two sets of functional units: 100 slaughter pig feed units and 1 kg of pig live weight.Results and discussionA similar relationship between cost and GWP impact was observed across all methods, although variability of GWP impact magnitude depending on method was observed. Reducing at an equivalent cost, GWP reduction ranged from 5.6 to 27% based on the pig feed functional unit, and 2.4 to 13% based on the pig live weight functional unit. Optimizing feed mixtures for GWP impacts resulted in significantly increased contributions to other impact categories, including a 56% increase in terrestrial ecotoxicity. Despite the increased contributions to other impact categories, all optimized feed mixtures achieved a reduction in endpoint indicators and single score. Endpoint reductions to the feed unit were 2.3–25% for ecosystem damage, 7.4–15% for human health, and 6.0–16% based on a single score value.ConclusionsThe findings emphasize the key importance of addressing LUC when optimizing the GWP of agri-food production. Suggestions are provided for areas of improvement in future optimization studies applying a dietary unit as the objective function, including additional midpoint impact categories and/or extended optimization covering whole areas of protection. The findings suggest that GWP impacts may be reduced at no additional cost if included or embedded in the pig feed formulation procedure.

Environmental impacts of oil extraction in blocks 16 and 67 of the Yasuní Reserve in the Amazonian Forest: Combined qualitative and Life-Cycle Assessment

This research analyses 24 years of oil extraction in blocks 16 and 67 of the Yasuní National Park (YNP) in the Amazonian Forest of Ecuador, one of the most biodiverse spaces in the world and with the current presence of ancient indigenous communities. As a novel contribution, we have carried out a Life-Cycle Assessment (LCA) that quantifies the footprints associated with the extraction, transportation, refining, distribution and final uses of the oil in four different scenarios (oil for asphalt use, electricity, marine fuel and passenger car transport). This study also sheds light on the energy return at the point of use of different oil-derivatives, and complements this with a qualitative analysis of the social, cultural and environmental implications for the Waorani communities. We conclude that the environmental burdens of the extraction process in blocks 16 and 67 in 2015 were greater than those of countries such as the United States, Saudi Arabia and Indonesia, based on the analysis of 11 impact categories. The blocks' operation is the most unfavourable for the categories of Terrestrial Acidification Potential (TAP), Global Warming Potential (GWP), Terrestrial Ecotoxicity Potential (TEP) and Ecosystem Quality Loss Potential (EQL), with increments of 804.15 %, 105.36 %, 506.29 % and 210.73 %, respectively, in relation to the average of the rest of the extraction systems analysed. Specifically, the present case study shows 75.18 % higher impacts in the blocks addressed, when compared to the Ecuadorian average. During the period 1999-2022, the carbon emissions associated with the oil extraction in these blocks have increased by 139.01%. It has been detected a neo-colonial economic behaviour: while the Ecuadorian state received 21% of the sales, the Spanish government and the oil companies received, on average, 38% and 41% of the per-litre average fuel price, respectively. Thus, 79% of the income stayed in the Global North. We conclude that, on average, 19.64 % of the impacts associated with crude oil production and consumption occur in the Amazonian region of the YNP, depending on the fuel used and the consumption mechanism. For the Global Warming Potential (GWP) impact category, the extraction process carries, on average, 34.51 % of the weight in all of the life-cycle impacts, depending on the consumption scenario. It was also estimated that to be able to use 0.33 kWh of electricity from fuel combustion, 0.47 kWh of energy for goods transport and 0.20 kWh for passenger transport, an investment of 1 kWh is required, with an average extended EROI of 1:3.33. According to the qualitative analysis performed, it has been concluded that the main local impacts are related to the obstacles in environmental monitoring and information, the economic dependence of the communities on the oil extraction company, and cultural transformations; impacts that are not easily quantifiable or detectable using other methodologies. The combination of the qualitative analysis and LCA showed that the neo-colonial economic distribution did not compensate the social and environmental impacts of the oil extraction occurred in the YNP.

Enhancing sustainability of urban waste management through data envelopment analysis for municipal solid waste composting in Tehran, Iran

The critical necessity of decreasing energy consumption and environmental effects is vital in various facets of urban life, particularly in urban waste management. This research aimed to evaluate the energy flow, CExD, and Life Cycle of a composting system for Municipal Solid Waste (MSW) in Tehran province, Iran. The initial phase entailed assessing the energy flow and effectiveness of the composting system, while the subsequent phase focused on enhancing energy efficiency through the application of Data Envelopment Analysis (DEA) to determine an optimal energy consumption strategy for conserving energy and reducing environmental impacts in Tehran's MSW composting system. Over a 90-day period, the analysis of energy usage revealed an energy input and output of 417.30 GJ (8500 t MSW)−1, with 227.02 GJ (8500 t MSW)−1 linked to transportation and 190.28 GJ (8500 t MSW)−1 related to composting activities. The overall energy consumption in the composting system was determined to be 6424.77 GJ (8500 t MSW)−1. By applying DEA optimization, energy savings of 14.45 GJ (8500 t MSW)−1 were accomplished in the composting process, with a significant reduction in electricity usage contributing to these savings. The environmental impact of the energy consumption patterns identified by DEA was notably lower compared to current energy practices. The most notable decrease in impact was observed in the Photochemical Oxidation category. By following the energy usage pattern recommended by DEA, the Global Warming Potential impact reduced by 500 kg CO2 eq. per 8500 t MSW. Additionally, the optimization of energy use through DEA led to a decrease in fossil energy resource depletion by around 4 GJ (8500 t MSW)−1 in the composting process.

Decreasing global tropical cyclone frequency in CMIP6 historical simulations.

The impact of anthropogenic global warming on tropical cyclone (TC) frequency remains a challenging issue, partly due to a relatively short period of reliable observational TC records and inconsistencies in climate model simulations. Using TC detection from 20 CMIP6 historical simulations, we show that the majority (75%) of these models show a decrease in global-scale TC frequency from 1850 to 2014. We demonstrated that this result is largely explained by weakened mid-tropospheric upward motion in CMIP6 models over the Pacific and Atlantic main development regions. The reduced upward motion is due to a zonal circulation adjustment and shifts in Intertropical Convergence Zone in response to global warming. In the South Indian Ocean, reduced TC frequency is mainly due to the decreased survival rate of TC seeds because of an increased saturation deficit in a warming climate. Our analysis highlights global warming's potential impact on the historical decrease in global TC frequency.

Assessing the global warming potential impact of organic fertilizer strategies in rice cultivation in Sri Lanka.

Rice is the staple food in Sri Lanka, and over 15% of the national land is allocated for rice cultivation. Greenhouse gas (GHG) emissions from rice fields account for 10% of national GHG emissions. The country has committed to reducing its emissions by 14.5% between 2010 and 2030 and achieving net zero emissions by 2060. In 2021, the country banned agro-fertilizer imports and opted for organic fertilizers, leading to a notable decrease in production and posing challenges to food security. However, the impact of adopting compost fertilizers alone remains unexplored. This study evaluated the global warming impact of two organic fertilizer strategies: switching to compost fertilizer instead of urea and applying rice straw compost instead of retaining crop residue. We applied the Denitrification and Decomposition model (DNDC 95) to rice field management data from Sri Lanka's Mahaweli H agricultural region. Simulations suggest that both strategies would increase the global warming potential of rice fields, mainly owing to elevated N2O emissions. This outweighs the mitigation benefits of avoiding crop residue retention and adding organic carbon through compost. Overall, our results point to the potential risk of shifting exclusively to compost-based fertilizers.

Combined bio-methanol and power production from bio-oil: Proposing a clean bio-process through waste heat recovery and environmental optimization

Traditional methanol production from natural gas is well-studied, but there is a lack of research on environmentally optimizing bio-based methanol production. This study focuses on optimizing the combined production of bio-methanol and power from bio-oil using a comprehensive bio-process model. The research includes a novel framework for environmental, technical, and economic optimization of bio-oil to methanol and power to determine the most eco-friendly and cost-effective approach. An organic Rankine cycle (ORC) is also integrated for waste heat recovery. The results of this study revealed that the bio-based process with ORC showed a 22.6 % reduction in global warming potential impact (GWP) per kilogram of methanol, compared to the bio-based process without ORC. Also, by implementing the most environmentally friendly process, GWP will be reduced by 70.6 % per kg methanol compared to base sub-optimal operation. The results showed that for the process with the addition of ORC, after performing multi-objective optimization, under the optimal conditions, the economic annual rate of return increased from 19.6 % to 34.7 %. Finally, it was revealed that if the considered technology is commercialized, for every percentage of the methanol market it gains, it will contribute to 2.176 million tons CO2-eq/year less emissions.

Comparison of Embodied Carbon Footprint of a Mass Timber Building Structure with a Steel Equivalent

The main purpose of this study is to quantify and compare the embodied carbon (EC) from the materials used or designed to build the Adohi Hall, a residence building located on the University of Arkansas campus in Fayetteville, AR. It has been constructed as a mass timber structure. It is compared to the same building design with a steel frame for this study. Based on the defined goal and scope of the project, all materials used in the building structure are compared for their global warming potential (GWP) impact by applying a life cycle assessment (LCA) using a cradle-to-construction site system boundary. This comparative building LCA comprises the product stage (including raw material extraction, processing, transporting, and manufacturing) plus transportation to the construction site (nodule A1–A4, according to standard EN 15804 definitions). In this study, GWP is primarily assessed with the exclusion of other environmental factors. Tally®, as one of the most popular LCA tools for buildings, is used in this comparative LCA analysis. In this study, the substitution of mass timber for a steel structure with a corrugated steel deck and concrete topping offers a promising opportunity to understand the GWP impact of each structure. Mass timber structures exhibit superior environmental attributes considering the carbon dioxide equivalent (CO2 eq). Emissions per square meter of gross floor area for mass timber stand at 198 kg, in stark contrast to the 243 kg CO2 eq recorded for steel structures. This means the mass timber building achieved a 19% reduction in carbon emissions compared to the functional equivalent steel structure within the building modules A1 to A4 studied. When considering carbon storage, about 2757 tonnes of CO2 eq are stored in the mass timber building, presenting further benefits of carbon emission delays for the life span of the structure. The substitution benefit from this construction case was studied through the displacement factor (DF) quantification following the standard process. A 0.28 DF was obtained when using mass timber over steel in the structure. This study provides insights into making more environmentally efficient decisions in buildings and helps in the move forward to reduce greenhouse gas (GHG) emissions and address GWP mitigation.

Cellulose nanocrystal filled synthetic rubber: Sustainable production, environmental assessment and end-of-life biodegradation by polyphagous pests

Plastic and rubber productions have reached staggering levels, leading to environmental concerns and accumulation of microplastics (MPs) rising in ecosystems. Rubber tires, a major source of MPs, pose further challenges due to excessive use of carbon black (CB) nanofillers in their manufacturing process, stresses on adding the element of sustainability to these products. This study emphasizes on the production of bio-based cellulose nanocrystals (CNC) filled synthetic rubber with sustainability assessment through life cycle assessment (LCA). It investigates the end-of-life (EOL) biodegradation potentials of rubber waste using a polyphagous pest, fall armyworm (FAW) (Spodoptera frugiperda). The results revealed that the production of CNC filled rubber demonstrate enhanced modulus compared to CB nanofillers, while requires substantial resource consumption, impacting abiotic resource depletion–fossil fuels (ADPf), freshwater ecotoxicity (CTUe), global warming potential (GWP), particulate matter (PM) and other impact categories. Emissions associated with CNC filled rubber during EOL phase are comparatively lower than CB, rendering CNC based rubbers a potentially viable choice from an environmental sustainability perspective. EOL pest biodegradation of CNC filled rubber showed negligible to no discernible physiological effects, potentially attributed to the presence of a diverse gut microbiota community in FAW (S. frugiperda). These findings highlight the relationship between physiochemical properties and CNC biodegradability in synthetic rubbers, aiding the development of sustainable EOL strategies for rubber waste management.

Transforming Turkish electricity system in the context of circular economy and green deal: impacts on steel and agricultural production

ABSTRACT Two important but conflicting goals in Turkey’s energy policy have been ensuring energy security through increased indigenous energy resource utilization and meeting the 2053 net zero emission commitment. Based on this, this work explores emission mitigation pathways for Turkey’s electricity system through circularity approaches of CO2 utilization and framework material recycling (FMR). Using mathematical models, eight life cycle impact potentials are evaluated including global warming potential (GWP). The extended impact on steel and agricultural production was also examined in the Green Deal context. The circularity approaches investigated showed that the GWP of Turkey’s wind, solar, and lignite energy sources reduce from the base values of 7.3 gCO2eq./kWh, 29.5 gCO2eq./kWh and 1130 gCO2eq./kWh to 2.72 gCO2eq./kWh, 21.08 gCO2eq./kWh and 241.26 gCO2eq./kWh, respectively. Fifty percent recycling ratio is also determined as the optimum for CO2 utilization and FMR. With this ratio, 21.84% CO2 emission reduction corresponding to 0.083 GT annual CO2 savings is achieved in the Turkish electricity mix. The decarbonization of electricity results in 25.0% and 27.0% GWP impact reductions in the agricultural and steel sectors, respectively. Hence, the decarbonization of electricity mix can significantly ease the negative impacts of the Green Deal on Turkey’s economy. Additionally, promoting and increasing the share of renewable energy sources in the electricity mix can further enhance these environmental benefits.

Carbon Assessment of a Wooden Single-Family Building—Focusing on Re-Used Building Products

Previous research has shown a lack of studies with comparisons between primary (virgin) and secondary (re-used) building materials, and their embodied emissions. The creation of different scenarios comparing the environmental impact of virgin vs. re-used materials is also motivated by the scarcity of raw materials in the world and the emergency of mitigating greenhouse gas (GHG) emissions from buildings. The aim of this study was to investigate scenarios, including new vs. re-used building products, applying the LCA method for a wooden single-family building. The findings showed a 23% reduction potential for total released (positive) CO2e when comparing the Reference scenario with Scenario I, using re-used wooden-based materials. Further, Scenario II, using all re-used building materials except for installations, showed a 59% CO2e reduction potential compared to the Reference scenario. Finally, Scenario III, which assumes all re-used building products, showed a 92% decreased global warming potential (GWP) impact compared to the Reference scenario. However, when including biogenic carbon and benefits (A5 and D module), the Reference scenario, based on newly produced wooden building materials, has the largest negative GHG emissions. It can be concluded that the re-use of building products leads to significant carbon savings compared to using new building products.

A comprehensive life-cycle assessment of plastic mulching for maize

While plastic mulch (PM) can increase crop yield, there are negative environmental impacts associated with the production, use and disposal of PM films. There is currently a gap in the literature on the negative impacts of PM throughout its entire life cycle, with most studies focusing on the global warming potential (GWP) only. The objective of this study is to conduct a life-cycle assessment (LCA) of PM to investigate the environmental impacts of all stages of mulching. The LCA was conducted using the SimaPro with data obtained from the relevant literature and ecoinvent database. The system boundaries include the production, transportation, installation, operation, removal and disposal of PM. The results reveal that the field operation of PM has the highest impact in GWP. A sensitivity analysis was also conducted and the GWP impact was observed to be sensitive to changes in carbon dioxide and net ecosystem carbon dioxide budget. The production of PM has the highest impact in abiotic depletion, but this impact can be reduced through energy recovery. Incineration yields the least harmful impacts, but the results of the study may vary depending on the exact disposal method. The impact of PM can be mitigated through proper waste management and mitigation measures, including regulations on disposal.

Attribution of Global Warming Potential impacts in a multifunctional metals industry system using different system expansion and allocation methodologies

PurposeIn order to reach a more circular economy, materials previously classified as waste can be upgraded and turned into valuable co-products, with associated environmental benefits. The generation of co-products raises many questions around the multifunctionality issue from a life cycle perspective. This article explores the attribution of Global Warming Potential (GWP) impacts for an ironmaking process, HIsarna, which additionally produces two co-products: zinc-rich process dust and slag, suitable for the zinc and cement sectors, respectively.MethodsA wide range of LCA allocation methodologies are applied to attribute impacts between the main product, hot metal, and the two co-products. These include system expansion, physical allocation, economic allocation and zero burden allocation. Each method attributes a different GWP to each co-product. Additionally, different perspectives are explored to consider the most suitable methods according to the co-product user and the co-product producer. For instance, it might be in the co-product user’s interest that the co-product GWP was minimised, and lower than other material inputs performing a similar function. Conversely, the co-product producer may be incentivised to lower its primary product’s GWP by attributing the greatest possible burden to the co-products.Results and discussionThe GWP impacts for zinc-rich process dust range from 0 to 3.71 kg CO2 eq. per kg. At the higher end, the GWP of zinc-rich dust would be higher than that of primary zinc concentrate. A similarly wide range is applicable for slag, 0 to 1.27 kg CO2 eq. per kg. This impacts the final GWP applied to HIsarna hot metal, which has an initial GWP of 1.72 kg CO2 eq. per kg but could decrease to 1.17 kg CO2 eq. per kg depending on the allocation methods employed. This would be a substantial reduction of over 30%, larger than many decarbonisation options that are predicted to provide. This scenario would also heavily burden the co-products and could be in conflict with interests of a co-product user seeking to utilise low emissions feedstocks as part of a decarbonisation strategy.ConclusionsThe reduction in GWP impact attributed to hot metal with the different approaches highlights the relevance of harmonizing the allocation methods used for co-products. The appropriateness of each of the approaches for attributing GWP impacts has been explored, offering insights as to how the benefits of such systems could be assessed and attributed in the future as circularity strategies and valuable co-products become more prevalent.

Importance of Strategic Environmental Assessment (Sea) Process and Environmental Health Impact Assessment (Ehia) Process Towards Sustainable Climate Change And Control

Importance of Strategic Environmental Assessment (Sea) Process and Environmental Health Impact Assessment (Ehia) Process Towards Sustainable Climate Change And Control

Global warming potential of lithium-ion battery cell production: Determining influential primary and secondary raw material supply routes

This study assesses the global warming potential (GWP) impacts of lithium-ion battery (LIB) recycling and subsequent cell production from primary and secondary raw materials. Furthermore, the study proposes multiple allocation strategies for the GWP impacts of LIB recycling, which range from 18 to 22 kg CO2 equivalent per kilowatt-hour NMC111 and NMC811 battery packs to determine the environmental burdens of secondary raw materials. The results demonstrate that using secondary raw materials could ideally reduce NMC111 and NMC811 cell production GWP by 30 %. In practice, GWP impact reductions will vary depending on factors, such as the contributions of primary production and recycling to battery raw material supply, and the market share of the different technologies employed within both primary production and recycling.Based on estimates for the availability of recycled raw materials to the European battery value chain, the sensitivity analysis methods identified NMC hydroxide, nickel sulfate, and battery-grade graphite as the most influential recycled raw materials on NMC111 cell production GWP. These materials received importance scores of 59%, 8%, and 6% respectively. Primary supply routes for cobalt sulfate received the highest importance score, followed by the primary supply routes of lithium carbonate and nickel sulfate. For NMC811 cells, nickel sulfate (34%), NMC hydroxide (27%) and graphite (8%) were identified as the most influential recycled raw materials, with the primary supply routes of nickel sulfate, lithium hydroxide and battery-grade graphite being the most influential.

Analyzing the global warming potential of the production and utilization of lithium-ion batteries with nickel-manganese-cobalt cathode chemistries in European Gigafactories

This study evaluates the global warming potential (GWP) impact of producing lithium-ion batteries (LIBs) in emerging European Gigafactories. The paper presents a cradle-to-gate (CTG) life cycle assessment (LCA) of nickel-manganese-cobalt (NMC) chemistries for battery electric vehicle (BEV) applications. We consider three scenarios to cover the most probable production routes in Germany, France, and Italy, foreseen as the largest European LIB producers by 2030. The energy demand for manufacturing considers two cases: electricity only and a mix of heat and electricity. The results show that European Gigafactories can reduce the overall GWP relative to 1 kWh of NMC battery, with respect to Chinese NMC LIBs, in a range of 32–60%. This corresponds to a decrease in equivalent CO2 emission of 32–81 kg CO2 eq., depending on the location, the energy demand and the NMC chemistry, if the whole production takes place in the facility. French Gigafactories obtain the upper bound of this reduction. A sensitivity analysis of the source of the lithium compound, used to produce the active cathode material, shows that increasing the nickel content decreases the GWP impact per kWh of battery capacity. However, NMC622 generates less equivalent CO2 than NMC811, for lithium compound produced from Chilean brine. In addition, a simplified analysis of the utilization phase of two different classes of BEVs shows the positive effects of the regional LIB production and of the low carbon intensity of the electricity mix.

A design stage, multi-objective assessment: material selection with environmental life-cycle analysis, labor, and material health considerations for building structure

During the schematic design stage of a building, assessing trade-offs of lifecycle impact of building elements and materials is crucial for the decision-making process when aiming to reduce negative impacts holistically. A multi-objective assessment is proposed, for environmental, labour exploitation risk (LER), and material health lifecycle impact of the structure and foundation elements in the schematic design stage. Using a real, mid-size, mass timber, educational building in Philadelphia, United States as a case study, we deployed multi-objective optimization (MOO) to consider the range of global warming potential (GWP), LER rating, and material health impact of nine product types over 1602 structure and foundation elements. The parametric workflow paired with Building Information Modelling (BIM) objects aims to provide designers a holistic overview on the cumulative, per material, and per building element impact upstream in the supply chain. The Pareto front solutions reveal that concrete floor with metal deck, hollow structural section framing, and concrete foundation slab, footing, and column pose the greatest risk overall for the case study building, and warrant design consideration to substitute with less impactful alternatives.

Evaluation of Waste Management Performance in Pariaman City Using Life Cycle Assessment (LCA)

Pariaman City's waste generation in 2022 is 38.26 tons/day. Waste management in Pariaman City is still not optimal, resulting in waste piling up in TPA South Tungkal. The waste reduction value at the research location after processing with BSF larvae can reduce 0.005 tons/day or 0.02% of the total waste generation in Pariaman City. The environmental impacts in waste management studied are Global Warming Potential (GWP), Acidification Potential (AP), and Eutrophication Potential (EP). Reducing the environmental impact of processing organic waste has been carried out, the smallest impact reduction results were obtained, namely in scenario 1, namely processing organic waste with BSF larvae in waste banks and TPS 3R. The results obtained were the impact characterization value from comparing several impact categories. GWP value 32,060,838.136 103 kg CO2-eq, AP 0.00246 x103 SO2-eq, and EP 0.00134 x103 kg PO4-3. So it can be concluded that scenario 1 has a smaller GWP, AP, and EP impact on the environment compared to scenario 0 and is used as the best alternative scenario for waste management in Pariaman City

Engineering characterization and environmental analysis of natural rubber latex modified asphalt mixture

Natural Rubber Latex (NRL) has attracted considerable interest as a resource for renewable paving materials due to its potential to lessen environmental impact. In order to gain a thorough understanding of the performance of NRL, this study evaluated the mechanical properties and environmental impact of Stone Mastic Asphalt (SMA) mixtures with a 6.6% binder content, 5% air voids content, and 5% NRL by weight of binder. The performance of this NRL asphalt mixture was compared to a control asphalt mixture using a commercially available polymer modified Styrene Butadiene Styrene (SBS) binder. The performance of the asphalt mixtures, such as their tensile strength, stiffness modulus, and resistance to fatigue and rutting, as well as their Global Warming Potential (GWP) impact, were studied. The results indicate that the addition of NRL increased tensile strength, stiffness modulus, and fatigue life in comparison to a conventional, unmodified asphalt mixture but had slightly lower values in comparison to the SBS mixture. Moreover, in terms of environmental concern, life-cycle assessment reveals that NRL-modified mixtures are more sustainable than SBS-modified mixtures in terms of GWP value.

Are single global warming potential impact assessments adequate for carbon footprints of agri-food systems?

The vast majority of agri-food climate-based sustainability analyses use global warming potential (GWP100) as an impact assessment, usually in isolation; however, in recent years, discussions have criticised the ‘across-the-board’ application of GWP100 in Life Cycle Assessments (LCAs), particularly of food systems which generate large amounts of methane (CH4) and considered whether reporting additional and/or alternative metrics may be more applicable to certain circumstances or research questions (e.g. Global Temperature Change Potential (GTP)). This paper reports a largescale sensitivity analysis using a pasture-based beef production system (a high producer of CH4 emissions) as an exemplar to compare various climatatic impact assessments: CO2-equivalents using GWP100 and GTP100, and ‘CO2-warming-equivalents’ using ‘GWP Star’, or GWP*. The inventory for this system was compiled using data from the UK Research and Innovation National Capability, the North Wyke Farm Platform, in Devon, SW England. LCAs can have an important bearing on: (i) policymakers’ decisions; (ii) farmer management decisions; (iii) consumers’ purchasing habits; and (iv) wider perceptions of whether certain activities can be considered ‘sustainable’ or not; it is, therefore, the responsibility of LCA practitioners and scientists to ensure that subjective decisions are tested as robustly as possible through appropriate sensitivity and uncertainty analyses. We demonstrate herein that the choice of climate impact assessment has dramatic effects on interpretation, with GWP100 and GTP100 producing substantially different results due to their different treatments of CH4 in the context of carbon dioxide (CO2) equivalents. Given its dynamic nature and previously proven strong correspondence with climate models, out of the three assessments covered, GWP* provides the most complete coverage of the temporal evolution of temperature change for different greenhouse gas emissions. We extend previous discussions on the limitations of static emission metrics and encourage LCA practitioners to consider due care and attention where additional information or dynamic approaches may prove superior, scientifically speaking, particularly in cases of decision support.