Mitigation Pathways Research Articles

Unlocking the potential of biogenic Ag@g-C3N4 in sustainable water purification: A kinetic and photocatalytic study

This research introduces a pioneering biogenic deposition-precipitation method for synthesis of Ag@g-C3N4 nanocomposites (NCs) employing fennel seed extract (FSE). This technique involves the reduction and capping of silver nanoparticles (AgNPs) onto g-C3N4, employing polyphenolic content of FSE, consequently establishing a strong Schottky junction. The, NCs were characterized through various spectroscopic and microscopic techniques, confirming successful biogenic deposition of AgNPs and purity of prepared nanomaterials. Further, the synthesized NCs were utilized for photocatalytic degradation of various hazardous pollutants viz. Rhodamine-B (Rh-B) dye, Tetracycline (TCy) antibiotic, Imidacloprid (IMD) insecticide and deactivation of E. coli microbes. Amongst the synthesized NCs, 3 wt% Ag@g-C3N4 NCs exhibited superior photocatalytic mitigation of Rh-B (99.26%, k = 90.4 × 10−3 min−1), TCy (96.86%, k = 40.2 × 10−3 min−1), IMD (95.7%, k = 34.96 × 10−3 min−1) and E. coli deactivation (99.5%, k = 49.19 × 10−3 min−1). Moreover, the rate constants revealed many-fold increase in photocatalytic degradation of pollutants, contrary to pristine g-C3N4 (k = 11.8 × 10−3 min−1). This investigation also unveils an intricate photocatalytic mitigation pathway for the aforementioned-contaminants, elucidating key role of superoxide radical anions in photocatalytic mitigation. One of the significant highlights of this research is the sustainable and cost-effective synthesis methodology involving fennel seeds, which not only ensures the wide availability of resources but also guarantees environmental safety, in alignment with green principles.

Potentials of greenhouse gas emission reduction through energy efficiency improvement in Iran's petrochemical sector

Reducing energy consumption and increasing energy efficiency is a key strategy to mitigate greenhouse gases (GHGs) in the petrochemical sector, both because of the high share of energy-related emissions and because of the economic attractiveness in terms of return on investment. This paper aims to calculate the GHG mitigation potentials of the energy reduction projects in Iran's petrochemical sector. firstly, we estimated the trend of GHG emissions until 2035 using data collected from the petrochemical complexes in Iran. Then, by assessing the energy audits and other studies, we calculated the energy consumption reduction potentials as well as their costs and benefits for petrochemical complexes. Finally, we modelled the energy supply and demand of the petrochemical sector in LEAP software to evaluate the mitigation potentials of the energy reduction projects. The results show that a 6.7 % emission reduction in the existing petrochemical complexes can be achieved with a capital of about 160 million dollars. The net present value of the projects will be about 2 billion dollars, and the cost of carbon reduction will be −60.7 dollars per ton. The results of this research can be used for policymakers to plan the mitigation pathway of the sector since the revenues obtained from the energy conservation measures can be used to fund capital-intensive GHG mitigation projects.

Techno-economic feasibility of CO2 utilization for production of green urea by Indian cement industries

The cement industry contributes substantially to global carbon emissions, necessitating urgent adoption of mitigation pathways aligned with climate goals. This study investigates the technical and economic viability of capturing carbon dioxide (CO2) emissions from cement plants in India and using that captured CO2 to produce green urea. The research aims to determine the feasibility of the CCUS approach as a practical way to reduce CO2 emissions from cement production while also boosting India's self-sufficiency in producing urea, a crucial fertilizer. The research uses a multi-criteria analysis (MCA) framework to assess various factors, including the technological readiness of CCUS technologies, the capital and operating costs of setting up and running such a system, the market demand for green urea, and the potential reduction in CO2 emissions. The study focused on 32 major cement plants in India, using data from their annual reports to inform the MCA model with an assumption of a post-combustion Monoethanolamine (MEA) scrubbing capacity CO2 capture capacity of 0.5 million tonnes per year per plant and used existing data and modeling techniques to analyze the feasibility of converting the captured CO2 into urea. The key findings indicate that this approach is promising and projects a 12.4% reduction in CO2 emissions from the cement industry if these 32 plants implement the CCUS technology. Additionally, it highlights a favorable market for the green urea produced, with an estimated output of 21.82 million tonnes per year, enough to offset a significant portion of India's reliance on urea imports. Financially, the study projects a six-year payback period and a 16.7% return on investment. It concludes that implementing CCUS technology to create green urea in Indian cement plants is technically and economically feasible. The approach has the potential to significantly reduce CO2 emissions while also supporting India's goal of self-sufficiency in urea production. However, further investigation and pilot-scale projects are recommended to validate the model's findings and optimize various aspects, such as managing flue gas impurities and leveraging waste heat for energy efficiency.

Feasible deployment of carbon capture and storage and the requirements of climate targets

Climate change mitigation requires the large-scale deployment of carbon capture and storage (CCS). Recent plans indicate an eight-fold increase in CCS capacity by 2030, yet the feasibility of CCS expansion is debated. Using historical growth of CCS and other policy-driven technologies, we show that if plans double between 2023 and 2025 and their failure rates decrease by half, CCS could reach 0.37 GtCO2 yr−1 by 2030—lower than most 1.5 °C pathways but higher than most 2 °C pathways. Staying on-track to 2 °C would require that in 2030–2040 CCS accelerates at least as fast as wind power did in the 2000s, and that after 2040, it grows faster than nuclear power did in the 1970s to 1980s. Only 10% of mitigation pathways meet these feasibility constraints, and virtually all of them depict <600 GtCO2 captured and stored by 2100. Relaxing the constraints by assuming no failures of CCS plans and growth as fast as flue-gas desulfurization would approximately double this amount.

Decomposing high uncertainty in greenhouse gas mitigation pathways in emerging regions: An approach to evaluate risks toward carbon neutrality

In the context of ambitious greenhouse gas (GHG) mitigation strategies in emerging regions, addressing the prevailing uncertainty and its key influential factors is crucial. While uncertainty analysis of GHG mitigation pathways has been extensively explored, the systematic identification and quantification of pivotal factors has been notably absent. This study introduces a novel methodology that combines Quasi-Monte Carlo simulation with Sobol variance decomposition, which identifies key influential factors and traces the flow of uncertainties. Applied in Anhui Province, a rapidly developing region in China, our findings indicate an uncertain GHG emission proportion of 6.2 % by 2030, escalating to 68.6 % by 2060, with a 95 % confidence interval. This uncertainty results in a cumulative projection error of 2.1 billion tons of CO2e from 2020 to 2070. The per capita GDP factor emerges as the predominant influence, alongside the increasing impact of renewable energy factor and UHV import electricity factor. In our uncertainty flow analysis, the energy transformation sector is identified as the principal contributor to total uncertainty, driven significantly by economic and energy-related factors. These results underscore the critical need for policymakers in emerging regions to incorporate uncertainty decomposition analysis into their strategic planning to mitigate risks in GHG reduction efforts.

Quantifying the effects of direct human activities and climate change on the spatial propagation of hydrological drought in the Yellow River Basin, China

The spatio-temporal evolution and propagation of flood and drought events are important in predicting their occurrences. This study attempted to investigate into the spatial propagation characteristics of hydrological droughts and their dynamics by identifying the spatial propagation probability (PP) and propagation time (PT) of different drought levels in the Yellow River Basin (YRB), China, based on copula functions and conditional probability. Then, the effects of direct human activities and climate change on the hydrological drought propagation were quantified by comparing the propagation characteristics of hydrological drought under observed and natural runoff. Results indicated that: (1) overall, the propagation of hydrological drought in the YRB showed a generally decreasing trend in PP and an increasing trend in PT with the increase of distance, presenting a gradually attenuating propagation along the river channel, the spatial propagation process of hydrological drought is similar to the domino effect; (2) when extreme hydrological drought occurred in the area represented by the Tangnaihai station located in the upstream basin, the probability of downstream areas experiencing moderate to severe hydrological drought showed an approximately decreasing trend along the river channel, with the PP of the observed sequence being slightly less than the natural sequence and the fluctuation of the hydrological drought propagation being more apparent; (3) taking 1986 as the dividing year, the average relative contribution rates of direct human activities to the changes in drought PT in spring, summer, autumn, and winter were 39.7%, 62.9%, 55.3%, and −67.2%, respectively, indicating a significant regulatory effect of reservoirs on hydrological drought propagation. In general, this study provided new insights into the spatial propagation mechanism of hydrological drought and offered a promising pathway for drought early warning and mitigation.

Hospital charge and resource use analysis of extended-spectrum penicillin antibiotic therapy after pancreatoduodenectomy in intermediate- and high-risk patients

BackgroundWe previously reported that an extended antibiotic mitigation pathway following pancreatoduodenectomy in patients with intermediate-/high-risk glands is associated with 83 % lower odds of clinically relevant postoperative pancreatic fistula (CR-POPF). We now describe associations between the pathway, resource utilization, and hospital charges. MethodsWe performed a retrospective cohort study of patients who underwent elective pancreatoduodenectomy with soft gland texture and fistula risk score (FRS) ≥3 who received standard or extended antibiotics. Hospital charges and resource utilization within 90 days of surgery were compared by CR-POPF status and antibiotic pathway. ResultsA total of 34 patients received extended antibiotics and 53 received standard antibiotics. In patients with CR-POPF, patients who received extended antibiotics had lower likelihood of surgical or percutaneous reintervention (75.0 % vs. 100.0 %, p = 0.022). Ninety-day postoperative charges associated with CR-POPF were higher than no CR-POPF ($60,527 vs. $25,631, p = 0.028). Our risk-based model predicted a $15,825 decrease in hospital charges per patient receiving extended antibiotics. ConclusionsCR-POPF is associated with higher 90-day hospital charges. Extended antibiotic therapy following pancreatoduodenectomy in patients with soft gland texture and FRS ≥3 is associated with fewer reinterventions in patients who develop CR-POPF. These outcomes will be formally tested in a randomized controlled trial (NCT05753735).

GOBLIN Lite: A National Land Balance Model for Assessment of Climate Mitigation Pathways for Ireland.

GOBLIN Lite: A National Land Balance Model for Assessment of Climate Mitigation Pathways for Ireland.

Methane slip and other emissions from newbuild LNG engine under real-world operation of a state-of-the art cruise ship

Liquefied natural gas (LNG) use as shipping fuel has increased in recent years. While LNG results in lower carbon dioxide (CO2) emissions as well as benefits in terms of air pollutants, the slip of unburned methane, the main component of LNG, has remained a concern. In this study, methane together with other climate warming agents, CO2 and black carbon (BC), as well as other emission compounds were characterized from 4-stroke low-pressure dual fuel engine on-board a newly build cruise ship utilizing LNG as well as marine gas oil (MGO). The brake specific methane slip was found to vary according to engine load, being 2.3–3.0 g/kWh at 54–80% loads, but increasing to 10 g/kWh at 25% load and 21 g/kWh at 12% load. The LNG combustion also resulted in higher formaldehyde emissions compared to MGO, but reduction in formaldehyde levels was observed over the SCR catalyst present in the exhaust line of the dual-fuel engine, without urea injection, suggesting it may provide a pathway for formaldehyde mitigation. In terms of particle emissions, LNG use reduced particle mass (PM) by 87–93% and BC by 94–99% compared to MGO combustion. Non-volatile particle number above 23 nm (PNnv,>23nm) and 10 nm (PNnv,>10nm) were reduced by 88–97% and 97–99%, except at lowest engine load where PNnv,>10nm increased by 26% compared to MGO utilization. When total greenhouse gas (GHG) emissions including CO2 and BC were considered, LNG use resulted in 13–15% lower GHG at high loads, but the benefit was undermined by the escaping methane at low load conditions. Following the engine activity profile during 8-months of vessel operation on the Mediterranean suggested, however, that in a diesel-electric cruise ship, low load conditions are used mainly during arrivals and departures from harbors, as the engine was operated at loads above 40% for 90% of the operation time. Weighted emission factor, representing the actual engine operation, resulted in methane slip of 2.8 g/kWh or 1.7% of the fuel use, which is below the value considered in the FuelEU Maritime. The results suggest that load specific methane slip, together with engine load profile should be considered when evaluating methane slip on vessel or fleet level.

GeoGOBLIN: A catchment-scale land balance model for assessment of climate mitigation pathways considering environmental trade-offs for multiple impact categories

GeoGOBLIN, a novel environmental impact and land balance assessment tool, builds upon the GOBLIN biophysical land use emissions model for Ireland, offering enhanced resolution and system-level detail. It combines remotely sensed data and national agricultural census data to model climate change, air quality, and eutrophication emissions at the catchment level. Integration of the CBM-CFS3 forest carbon modelling framework (utilised in Ireland's National Inventory Report) increases alignment with national emissions reporting. GeoGOBLIN disaggregates emissions by life cycle assessment impact categories, making it a valuable tool for policymakers and researchers evaluating environmental and economic trade-offs associated with land-use scenarios. Illustrative scenarios demonstrate GeoGOBLIN's ability to assess the multifaceted impacts of alternative land uses, supporting informed decision-making for sustainable land use, food production, and a circular bioeconomy.

Evaluating the near- and long-term role of carbon dioxide removal in meeting global climate objectives

The 6th Assessment Report from the Intergovernmental Panel on Climate Change lacked sufficient land-sector scenario information to estimate total carbon dioxide removal deployment. Here, using a dataset of land-based carbon dioxide removal based on the scenarios assessed by the Intergovernmental Panel on Climate Change, we show that removals via afforestation and reforestation play a critical near-term role in mitigation, accounting for around 10% (median) of the net greenhouse gas emission reductions between 2020 and 2030 in scenarios that limit warming to 1.5 °C with limited overshoot. Novel carbon dioxide removal technologies such as direct air carbon capture and storage scale to multi-gigatonne levels by 2050 and beyond to balance residual emissions and draw down warming. We show that reducing fossil fuel and deforestation emissions (gross emissions) accounts for over 80% of net greenhouse gas reductions until global net zero carbon dioxide (CO2) independent of climate objective stringency. We explore the regional distributions of gross emissions and total carbon dioxide removal in cost-effective mitigation pathways and highlight the importance of incorporating fairness and broader sustainability considerations in future assessments of mitigation pathways with carbon dioxide removal.

Cys fluorescent probe precisely modified by fluorine revealing oxidative stress mechanism in Parkinson's disease

Oxidative stress is considered the fundamental pathophysiological mechanism of neurodegenerative diseases such as Parkinson's. Nuclear factor erythroid 2-related factor 2 (Nrf2), as a critical transcription factor for antioxidant response, activating its regulation of biothiol level is deemed an essential pathway for disease mitigation. Cysteine (Cys), an abundant and active biothiol, is a crucial molecule in this antioxidant pathway. To further elucidate these regulatory mechanisms, a specific, rapid, blood-brain barrier-crossing Cys fluorescent probe was demanded. Therefore, we selected isophorone as the parent compound, with bromoacetyl ester as the site responsive to Cys. By introducing fluorine only at the ortho position of bromoacetyl ester, utilizing fluorine's strong electron-withdrawing ability to activate the electrophilicity of methylene and carbonyl groups, probe WSX-F achieved specific and rapid response to Cys. Meanwhile, fluorine lengthened the probe's fluorescence emission wavelength and improved lipophilicity. In situ probe imaging revealed that the activated antioxidant mechanism for Nrf2 will up-regulate the level of Cys cells and the brain in Parkinson's disease, and the differential distribution of Cys in the Parkinson's brain region. The research provided theoretical guidance for preventing and treating Parkinson's disease.

Fossil materials demand within deep decarbonization scenarios: A feasibility assessment

Integrated Assessment Models (IAMs) are cornerstone tools in guiding decarbonization policies. However, the petrochemical sector, which is crucial to the future of oil and gas due to its non-energy fossil feedstock demands, has been overlooked in IAMs. This study aims to evaluate the implications of this under-representation on decarbonization strategies. We assessed the Illustrative Mitigation Pathways from the Intergovernmental Panel on Climate Change in its Sixth Assessment Report. Our analysis indicates that, without stringent material policies, the feedstock demand can reach unattainable levels from 2050 onwards. This is evidenced by the required disruptive yields of primary oil in feedstocks, which exceed 80 % in some cases. The findings highlight the necessity for improved modelling of the petrochemical sector within IAMs.

Uneven consequences of global climate mitigation pathways on regional water quality in the 21st century

Future socioeconomic climate pathways have regional water-quality consequences whose severity and equity have not yet been fully understood across geographic and economic spectra. We use a process-based, terrestrial-freshwater ecosystem model to project 21st-century river nitrogen loads under these pathways. We find that fertilizer usage is the primary determinant of future river nitrogen loads, changing precipitation and warming have limited impacts, and CO2 fertilization-induced vegetation growth enhancement leads to modest load reductions. Fertilizer applications to produce bioenergy in climate mitigation scenarios cause larger load increases than in the highest emission scenario. Loads generally increase in low-income regions, yet remain stable or decrease in high-income regions where agricultural advances, low food and feed production and waste, and/or well-enforced air pollution policies balance biofuel-associated fertilizer burdens. Consideration of biofuel production options with low fertilizer demand and rapid transfer of agricultural advances from high- to low-income regions may help avoid inequitable water-quality outcomes from climate mitigation.

Urban green spaces, self-rated air pollution and health: A sensitivity analysis of green space characteristics and proximity in four European cities

Exploring the influence of green space characteristics and proximity on health via air pollution mitigation, our study analysed data from 1,365 participants across Porto, Nantes, Sofia, and Høje-Taastrup. Utilizing OpenStreetMap and the AID-PRIGSHARE tool, we generated nine green space indicators around residential addresses at 15 distances, ranging from 100m to 1500m. We performed a mediation analysis for these 135 green space variables and revealed significant associations between self-rated air pollution and self-rated health for specific green space characteristics. In our study, indirect positive effects on health via air pollution were mainly associated with green corridors in intermediate Euclidean distances (800-1,000m) and the amount of accessible green spaces in larger network distances (1,400–1,500m). Our results suggest that the amount of connected green spaces measured in intermediate surroundings seems to be a prime green space characteristic that could drive the air pollution mitigation pathway to health.

Plant-level green transformation strategy in China's cement industry: Considering energy conservation and emission reduction co-benefits

The green transformation strategy is critical for achieving the emission mitigation targets in China's cement study. However, previous studies have focused on the nationwide industry level and overlooked the significant differences in the cement plants, remaining the risk of difficulties in implementing the proposed strategy. To overcome this problem, this study proposes a framework for plant-level green transformation strategy based on the industry-level emission mitigation pathway and a plant-level cement database. The strategy indicates the cement plants that need to be shut down, be retrofitted, and promote technologies. Results show that 1005 clinker and 3706 cement production plants should be shut down or retrofitted, while 60%+ of the plants should take denitrification and dust removal technologies in 2019–2035. The plant-level strategy can achieve energy conservation and CO2, SO2, NOx, and PM reductions by 40.0–79.9%, demonstrating the existence of the co-benefits. As only 4.1%–25.0% of the plants contribute half of the energy conservation and emission reduction effects, the plant-level strategy leads to significant spatial heterogeneity of the co-benefits. For example, the energy conservation and emission reduction potential in the five largest cement producer cities varies from over 30%. In addition, the total fixed investment is 99.6 billion Chinese Yuan (CNY) and the highest cost is 12.8 billion CNY/a, which will not cause heavy economic burdens to the industry. This study bridges the industrial-level planning and plant-level implementation of the green transformation strategy, whose methodology supports the synergic energy conservation and emission reduction in China's cement industry and beyond.

Advancing cost-optimal residential decarbonisation pathways: An examination of heat pumps and thermal efficiency

In Ireland, residential energy policy has been influenced by thermal inefficiency, high electricity prices and energy poverty. These factors have driven the fabric-first approach, where buildings must undergo extensive thermal retrofitting to qualify for heat pump subsidies. The cost-effectiveness of this approach has not been properly scrutinised to date. This paper addresses this knowledge gap by exploring the cost-effectiveness of the fabric-first approach and other decarbonisation strategies for the residential sector and broader energy system. The study develops scenarios by modifying the Heat Loss Indicator (HLI) threshold, which evaluates the fabric and ventilation heat loss per unit of floor area and is used to determine heat pump subsidy eligibility. The paper also considers scenarios that permit installing sub-optimal performing heat pumps that do not achieve peak performance levels in dwellings with higher HLIs. The analysis uses the TIMES-Ireland Model (TIM), a model of the whole energy system that reflects the interdependence of mitigation pathways across different energy sectors. Our study shows that Ireland's fabric-first approach requires 22 times more thermal retrofits to meet climate targets than alternative pathways. The alternative pathways based on the latest heat pump performance data are more cost-effective, showing that higher heat pump HLI thresholds can reduce the average sectoral marginal CO2 emission price by 60% compared to the current fabric-first approach. The cost savings indicate that shifting to an HLI threshold of 2.3 W/K/m2 is close to optimal, while cost savings are minimal when moving from an HLI of 2.3 to 3 W/K/m2. Furthermore, electricity prices and household awareness are essential to the cost-optimal transition to residential heat pumps.

Carbon performance analysis of upgraded wastewater treatment plants in key control areas of the Ziya River Basin in China

Wastewater treatment plants (WWTPs) are one of the largest sources of greenhouse gas (GHG) emissions, and they are also one of the largest energy consumption industries in urban systems. With the progression of upgrading and standard-rising, WWTPs both directly and indirectly increase carbon emissions from the increased investments in facilities and usages in electricity as well as chemical agents. Here, we collected operational data from 15 WWTPs in the key control areas of the Ziya River Basin in North China and accounted for the changes in carbon performance at different technical upgrade methods. Results showed that the average carbon emission performance increased by 0.487 kg CO2/m3 after the upgrade. Carbon emissions from electricity consumption, chemical usage, biochemical process and sludge treatment accounted for 42%, 17%, 24%, and 17% of the total improvement in carbon emission performance, respectively. Reducing energy consumption, regulating chemical use and sludge comprehensive utilization are the key to carbon emission reduction. It further proposes that the development of wastewater treatment discharge standards should fully consider the comprehensive utilization of water quality classification. Regions with favorable natural conditions should make full use of their advantages by adopting economically feasible, low-energy-consuming technologies such as constructed wetlands, which offer carbon sequestration and landscaping benefits. This study provides guidance on the selection of technological pathways for pollution reduction and carbon mitigation in the wastewater treatment industry and on achieving sustainable water resource utilization.

Selecting Indonesia’s Iron and Steel Industry Mitigation Pathways Based on AIM/End-use Assessment

The measurement of mitigation pathways is important for Indonesia’s iron and steel industry in terms of reducing GHG emissions. This study conducted a cost-effectiveness analysis to assess the economic impacts with associated emission reduction potential of different mitigation strategies by developing an Abatement Cost Curve (ACC) that selects the mitigation option based on the logic of the AIM/End-use model up to 2050. The model was established through the baseline scenario, and the following appropriate mitigation options: adjusting the production structure (CM1), increasing energy efficiency by promoting low carbon technology and non-blast furnace technology that is un-implemented early in modeling years in Indonesia will be included for future reference (CM2), and switching from fossil fuels to low emission fuels (CM3). Results show that the selected technology roadmap from the abatement cost curve below carbon tax 110 US$/tCO2e in 2050 could lead to the most optimal emission reduction of 19.8 MtCO2e, 50.2 MtCO2e, 54.84 MtCO2e with investment costs 93.55 million US$, 1086 million US$, and 1183 million US$ in the scenarios CM1, CM2, and CM3, respectively. The effectiveness of each mitigation action reveals that energy savings and emission reduction from energy will rely mostly on promoting low-carbon technologies. The most effective strategy to reduce emissions from IPPU is to adjust the production structure.

Current Concerns about Microplastics and Nanoplastics: A Brief Overview.

The widespread and increasing use of plastic-based goods in the present-day world has been raising many concerns about the formation of microplastics, their release, their impacts on the environment and, ultimately, on living organisms. These concerns are even greater regarding nanoplastics, i.e., nanosized microplastics, which may have even greater impacts. In this brief review, although without any claim or intention to exhaustively cover all the aspects of such a complex and many-sided issue, the very topical problem of the formation of microplastics, and the even more worrisome nanoplastics, from polymer-based products was considered. The approach is focused on a terse, straightforward, and easily accessible analysis oriented to the main technological engineering aspects regarding the sources of microplastics and nanoplastics released into the environment, their nature, some of the consequences arising from the release, the different polymers involved, their technological form (i.e., products or processes, with particular attention towards unintentional release), the formation mechanisms, and some possible mitigation pathways.