Ozone Depletion Research Articles

Environmental sustainability, energy efficiency and uncertainty analysis of agricultural residue-based bioethanol production: A comprehensive life cycle assessment study

Bioethanol produced from agro-residue provides a sustainable alternative to fossil fuels, mitigating pollution, reducing waste, and promoting a circular economy. However, challenges arise in sustainable sourcing, resource conflicts, water quality concerns, and managing environmental footprints to maximize agro-residue-based bioethanol benefits. The environmental impacts, net energy ratio (NER), net energy value, water footprint, and uncertainties associated with bioethanol production from agro-residues are analyzed in this study. The analysis followed a cradle-to-gate approach using 1 L of bioethanol produced as a functional unit (FU), allowing for a direct comparison of the environmental performance of the different feedstocks. The result shows that rice straw-based bioethanol exhibited higher environmental impacts, particularly in terms of ecotoxicity, ionizing radiation, human toxicity, and ozone layer depletion, except for greenhouse gas emission, which is lowest for corn stover (0.37 kg CO2 eq. per FU) and highest for cassava straw (1.1 kg CO2 eq. per FU). Furthermore, the Cumulative Energy Demand analysis highlighted a significant reliance on fossil fuels from agricultural biomass throughout the bioethanol production process. The energy balance analysis shows that the agricultural residues are feasible for bioethanol production with NER of 1.20, 3.10, and 3.28 for rice straw, corn stover, and cassava straw, respectively. To enhance the accuracy and reliability of the LCA results, Monte Carlo simulation was employed to account for uncertainty and variability in the data. This methodology provides a better understanding of the impacts of bioethanol production, with a focus on sustainability and advancements in reducing our reliance on fossil fuels.

Position-specific kinetic isotope effects for nitrous oxide: a new expansion of the Rayleigh model

Abstract. Nitrous oxide (N2O) is a potent greenhouse gas and the most significant anthropogenic ozone-depleting substance currently being emitted. A major source of anthropogenic N2O emissions is the microbial conversion of fixed nitrogen species from fertilizers in agricultural soils. Thus, understanding the enzymatic mechanisms by which microbes produce N2O has environmental significance. Measurement of the 15N / 14N isotope ratios of N2O produced by purified enzymes or axenic microbial cultures is a promising technique for studying N2O biosynthesis. Typically, N2O-producing enzymes combine nitrogen atoms from two identical substrate molecules (NO or NH2OH). Position-specific isotope analysis of the central (Nα) and outer (Nβ) nitrogen atoms in N2O enables the determination of the individual kinetic isotope effects (KIEs) for Nα and Nβ, providing mechanistic insight into the incorporation of each nitrogen atom. Previously, position-specific KIEs (and fractionation factors) were quantified using the Rayleigh distillation equation, i.e., via linear regression of δ15Nα or δ15Nβ against [-fln⁡f/(1-f)], where f is the fraction of substrate remaining in a closed system. This approach, however, is inaccurate for Nα and Nβ because it does not account for fractionation at Nα affecting the isotopic composition of substrate available for incorporation into the β position (and vice versa). Therefore, we developed a new expansion of the Rayleigh model that includes specific terms for fractionation at the individual N2O nitrogen atoms. By applying this Expanded Rayleigh model to a variety of simulated N2O synthesis reactions with different combinations of normal, inverse, and/or no KIEs at Nα and Nβ, we demonstrate that our new model is both accurate and robust. We also applied this new model to two previously published datasets describing N2O production from NH2OH oxidation in a methanotroph culture (Methylosinus trichosporium) and N2O production from NO by a purified Histoplasma capsulatum (fungal) P450 NOR, demonstrating that the Expanded Rayleigh model is a useful tool in calculating position-specific fractionation for N2O synthesis.

Life Cycle Assessment of Banned Single-Use Plastic Products and Their Alternatives

Plastic and microplastic contamination continue to be growing problems across the globe for both ecosystems and human health. Canada has banned single-use plastic products such as bags, cutlery, and foodservice ware (containers) to address and mitigate plastics and microplastic contamination. This study evaluates the life cycle of banned plastic products and their alternatives to determine whether environmental impacts can be mitigated. The environmental impacts of bags (plastic, paper, cotton), cutlery (plastic, wooden, biodegradable), and containers (plastic, styrofoam, biodegradable) were determined considering both domestic and imported products. The bag study saw paper bags having the highest environmental impacts and cotton bags with the lowest due to their reusability. For the cutlery study, plastic cutlery was the most impactful across all categories except for eutrophication and ozone depletion, where biodegradable cutlery was the most impactful by 25% and 35%, respectively. In the case of foodservice ware (containers), styrofoam was found to be the least impactful. Similar to cutlery, the plastic containers had the greatest impact except where the biodegradable container contributed more to ozone depletion and eutrophication by 25% and 45%, respectively. Local production reduced impacts across all categories. Furthermore, on a local scale, biodegradable cutlery had a greater impact on the smog and respiratory effects categories than plastic by 10% and 30%, respectively. The results of this study indicate that future regulations should focus on promoting and educating consumers on the use of reusable products over single-use products, funding research to mitigate challenges associated with waste management, and consider an informed ban on all single-use products and not just those made of plastic material to mitigate environmental impacts.

Planetary risk society: from ignored problems to fast solutions

ABSTRACT This article compares the slow response time to the dangers posed by greenhouse gases to the swift move to phase-out ozone-depleting substances after the 1985 discovery of the ‘ozone hole’. I suggest both commercial and psychological factors account for the disparity in reactions, in particular the perceived ability to distance ourselves from the risks and uncertainties that our economic activities create. To prevent irreversible damage to the Earth System, I further argue it is crucial to minimise the time that elapses between recognising emerging problems and taking concrete action to address them. Finally, I outline the implications of these case studies for the global chemical industry, where the rapid introduction of novel entities requires a bold regulatory response to safeguard our planet.

Effects of mineral fertilization (NPK) on combined high temperature and ozone damage in rice

BackgroundIncreasing concern has recently been highlighted regarding crop damage due to extreme weather events caused by global warming and the increased production of ground-level ozone. Several studies have investigated rice growth in response to fertilization conditions under various environmental stress conditions; however, studies on growth development in response to fertilization conditions under combined high-temperature/ozone treatment conditions are scarce. In this study, we aimed investigate the growth and physiological development of rice under combined high temperature and ozone treatment conditions and to reveal the damage-mitigation effects of NPK fertilization treatments.ResultsThe plants were treated with varying levels of NPK [N2 (N-P-K: 9.0-4.5-4.0 kg/a), P2 (4.5-9.0-4.0 kg/a), K2 (4.5-4.5-8.0 kg/a), and control (4.5-4.5-4.0 kg/10a).] under combined high-temperature (35 ℃) and ozone (150 pb) treatment conditions. Analysis of the growth metrics, including plant height, leaf age, dry weight, and the plant height/leaf age (PH/L) ratio were revealed that combined high-temperature/ozone treatment promoted the phenological development indicated by increasing leaf age but decreased the plant height and dry weight indicating its negative effect on quantitative growth. The effects of this combined high-temperature/ozone treatment on growth were alleviated by NPK fertilization, particularly in K2 treatment but worsened in N2 treatment. Visible damage symptoms in rice leaves induced by exposure to the combined stressors was also alleviated by the K2 treatment. At the physiological level, K2 treatment reduced the expression of OsF3H2, which is associated with antioxidant activity, suggesting that potassium improved stress tolerance. Additionally, expression of genes related to abscisic acid (ABA) metabolism showed increased OsNECD (ABA synthesis) and decreased OsCYP707A3 (ABA degradation) in the K2 treatment, promoting a stronger adaptive stress response. Stomatal conductance measurements indicated a slight increase under K2 treatment, reflecting enhanced regulation of stomatal function during stress.ConclusionThe study highlights the potential of potassium fertilization to mitigate combined high-temperature and ozone stress in rice, suggesting it as a strategy to improve crop resilience and optimize fertilization. The findings offer insights into fertilization treatments and can guide future research on stress tolerance in crops.

Environmental Benefits of Hydrogen-Powered Buses: A Case Study of Coke Oven Gas

This study conducted a Life Cycle Assessment (LCA) of alternative (electric and hydrogen) and conventional diesel buses in a large metropolitan area. The primary focus was on hydrogen derived from coke oven gas, a byproduct of the coking process, which is a crucial step in the steel production value chain. The functional unit was 1,000,000 km traveled over 15 years. LCA analysis using SimaPro v9.3 revealed significant environmental differences between the bus types. Hydrogen buses outperformed electric buses in all 11 environmental impact categories and in 5 of 11 categories compared to conventional diesel buses. The most substantial improvements for hydrogen buses were observed in ozone depletion (8.6% of diesel buses) and global warming (29.9% of diesel buses). As a bridge to a future dominated by green hydrogen, employing grey hydrogen from coke oven gas in buses provides a practical way to decrease environmental harm in regions abundant with this resource. This interim solution can significantly contribute to climate policy goals.

Variations of Planetary Wave Activity in the Lower Stratosphere in February as a Predictor of Ozone Depletion in the Arctic in March

This study is dedicated to the investigation of the relationship between the wave activity in February and temperature variations in the Arctic lower stratosphere in March. To study this relationship, the correlation coefficients (CCs) between the minimum temperature of the Arctic lower stratosphere in March (Tmin) and the amplitude of the planetary wave with zonal number 1 (PW1) in February were calculated. Tmin determines the conditions for the formation of polar stratospheric clouds (PSCs) following the chemical destruction of the ozone layer. The NCEP and ERA5 reanalysis data and the modern and future climate simulations of the Earth system models INM CM5 and SOCOLv4 were employed. It is shown that the maximum significant CC value between Tmin at 70 hPa in the polar region in March and the amplitude of the PW1 in February in the reanalysis data in the lower stratosphere is 0.67 at the pressure level of 200 hPa. The CCs calculated using the model data are characterized by maximum values of ~0.5, also near the same pressure level. Thus, it is demonstrated that the change in the planetary wave activity in the lower extratropical stratosphere in February can be one of the predictors of the Tmin. For further analysis of the dynamic structure in the lower stratosphere, composites of 10 seasons with the lowest and highest Tmin of the Arctic lower stratosphere in March were assembled. For these composites, differences in the vertical distribution and total ozone content, surface temperature, and residual meridional circulation (RMC) were considered, and features of the spatial distribution of wave activity fluxes were investigated. The obtained results may be useful for the development of forecasting of the Arctic winter stratosphere circulation, especially for the late winter season, when substantial ozone depletion occurs in some years.

Unexplained high and persistent methyl bromide emissions in China

Methyl bromide (CH3Br) is an important ozone-depleting substance whose use is regulated under the Montreal Protocol. Quantifying emissions on the national scale is required to assess compliance with the Montreal Protocol and thereby ensure the timely recovery of the ozone layer. However, the spatial-temporal patterns of China’s national CH3Br emissions remain unclear. Here we estimate the national emissions of CH3Br in China during 2011−2020 using atmospheric observations at 10 sites across China combined with an inversion technique (top-down) and compare those with an updated inventory of identified emission sources (bottom-up). Measured CH3Br mole fractions are enhanced well above the background mole fractions, especially at sites in eastern China. Top-down emission estimates exceed bottom-up estimates by 5.5 ± 1.4 gigagrams per year, with the largest fraction (60%) of observationally derived CH3Br emissions arising from underestimated or unidentified emissions sources. This study shows the potential impacts of the unaccounted emissions on stratospheric ozone depletion, with implications for the Montreal Protocol.

Going beyond carbon: Influence of structural parameters on the environmental impacts of typical building structures

The construction sector has a large impact on the environment, be it climate change, biodiversity loss or resources depletion. Part of those impacts comes from construction materials, and more specifically, concrete and steel building structures. Early-stage design tools including environmental damage assessment are therefore required to achieve sustainable construction practices. This article presents a parametric approach aiming at studying the influence of early-stage structural parameters on the environmental impacts of a structure. The developed methodology combines parametric structural design with a multicriteria cradle-to-grave Life Cycle Assessment, applied to typical housing structures such as grid based beam column structures with a central core for lateral stability. Results show that span, number of levels and materials greatly influence the environmental impacts of considered structures. Climate change scores per floor area range from 80 kgCO2/m2 for short span timber structure to 215 kgCO2/m2 for long span steel buildings with few levels. Beams and slabs have the largest contribution in such impacts. Changing the production processes of materials is a way to reduce greenhouse gas emissions. However, decarbonizing steel production processes or reducing the cement content of concrete participate in burdenshifting with increased scores in several impact categories, such as carcinogenic toxicity or ozone depletion.

Analysis of Ozone Pollution and Precursor Control Strategies in the Pearl River Delta During Summer and Autumn Transition Season

To analyze the causes of ozone pollution in the Pearl River Delta （PRD） Region during the summer and autumn transition seasons, a case study was carried out in Guangzhou, which is located in the center of the PRD Region, to analyze the ozone photochemical production and destruction pathways as well as emission reduction scenarios using a box model based on comprehensive observation. The results showed that the stagnant meteorological conditions and high temperature during the observation period were suitable for the photochemical production of ozone, which led to widespread and prolonged ozone pollution. Aromatic hydrocarbons （AHs） contributed the most to the ozone formation potential （OFP）, and m/p-xylene, toluene, and o-xylene were the major three VOC species contributing to the OFP. Box model analysis revealed that the averaged net O3 production rate during the polluted period was 23.2×10-9 h-1 and the peak reached 39.2×10-9 h-1. The HO2·+NO and NO2+·OH reaction pathways contributed the most to the local photochemical ozone production （51.2%） and destruction （47.0%）, respectively. Observed ozone concentration was primarily controlled by both the local photochemical O3 production and the export-dominated transport. The RIR and EKMA analyses showed that O3 formation in Guangzhou during the summer-autumn transition seasons was mainly a VOC-limited regime and AHs showed the greatest sensitivity to O3 production. Toluene, m/p-xylene, o-xylene, n-butane, and propylene were the five key components affecting O3 generation. The analysis of reduction scenarios showed that reducing anthropogenic VOC emissions was the most favorable way to reduce O3 concentrations； however, if NOx emission was controlled after reducing VOCs, the O3 concentration would rebound in a short time. Our results suggested that the synergistic reduction of VOCs and NOx while mainly focusing on VOCs alleviation should be implemented to continuously reduce ozone concentrations in the future.

Solar cells combined with geothermal or wind power systems reduces climate and environmental impact

This research investigates the environmental sustainability of three integrated power cycles: combined geothermal-wind, combined solar-geothermal, and combined solar-wind. Here, a promising solar technology, the perovskite solar cell, is considered and analysed in conjunction with another renewable-based cycle, evaluating 17 scenarios focusing on improving the efficiency and lifespan. Among the base cases, combined solar-wind had the lowest ozone depletion impact, while combined geothermal-wind had the lowest freshwater ecotoxicity and marine ecotoxicity impacts. The study shows that extending the perovskite solar cell lifespan from 3 to 15 years reduces CO2 emissions by 28% for the combined solar-geothermal and 56% for the combined solar-wind scenario. The most sustainable cases in ozone depletion, marine ecotoxicity, freshwater ecotoxicity, and climate change impacts are combined solar-wind, combined solar-geothermal, and combined geothermal-wind, respectively, among all evaluated scenarios. This research suggests investing in the best mix of integrated power cycles using established and emerging renewable technologies for maximum environmental sustainability.

Implementation of the Requirements of the Montreal Protocol on Substances that Destroy the Ozone Layer in the Russian Federation

The current international problem of reducing production and consumption of substances that deplete the ozone layer and compliance with the requirements of the Montreal Protocol is considered. Customs statistics of the Russian Federation on foreign trade in terms of imports and exports of ozone-depleting substances (including controlled substances of list F) for 2022 are analysed. The reporting of legal entities and individual entrepreneurs regarding the production and destruction of ozone-depleting substances (including controlled substances of list F) for 2022 was studied. It is shown that the Russian Federation complies with the requirements of the Montreal Protocol on substances that deplete the ozone layer and is systematically reducing the permissible annual consumption of ozone-depleting substances (including schedule F controlled substances).

Demonstration of a physical inversion scheme for all-sky, day-night IASI observations and application to the analysis of the onset of the Antarctica ozone hole: Assessment of retrievals and consistency of forward modeling

Based on a recently developed all-sky forward model (σ-IASI/F2N) for the computation of spectral radiances in the range 100 to 2760 cm-1, the paper addresses the spring onset of the Antarctica ozone hole with infrared observations from the IASI (Infrared Atmospheric Sounder Interferometer) satellite sounder. The Antarctica ozone hole is a cyclic event that grows in normal conditions in late August and collapses in late November/early December. Because of climate change (cooling of the stratosphere), the O3 hole is expected to become deeper. Indeed, 2021 and 2023 have been characterized by very spatially extensive and deep ozone hole. To demonstrate that we can gain further insights into these phenomena with the help of infrared nadir viewing observations, we have developed an all-sky retrieval tool, which inverts the whole IASI infrared spectrum to simultaneously estimate thermodynamic and geophysical parameters, including ozone and nitric acid, which are key parameters in analyzing the Antarctic ozone hole. Infrared sounders acquire data day and night, unlike visible and ultraviolet sounders, which are only operational during daytime. This enables us to acquire data also during the polar night, which is a critical time for O3 hole formation. Ice polar stratospheric clouds have been identified and fitted with our scheme. Maps of atmospheric ozone, complemented with those of nitric acid, temperature, and lower stratosphere height, have been retrieved for July, September, and October 2021 and 2023. Results are compared to those derived from TROPOMI (TROPOspheric Monitoring Instrument) and OMI (Ozone Monitoring Instrument), showing a very good agreement. The comparison of simultaneously retrieved O3 and HNO3 shows that the onset of the ozone hole is associated with relevant denitrification in the Antarctica Stratosphere. For 2023, our findings also show that O3 depletion episodes began as early as July. Although demonstrative, our analysis evidences the importance of Numerical Weather Prediction centers to assimilating all-sky infrared radiances (day, night, clear, or with ice or water clouds) to get insights into providing a more comprehensive picture of the Southern Spring ozone depletion over Antarctica.

Life Cycle Assessment (LCA) of Single Jersey Knitted Fabrics Containing Recycled Cotton Fiber and Fabric Performance

This study investigates the life cycle assesment of single jersey knitted fabrics containing recycled cotton and their some performance properties. In the yarn production stage fibers obtained from waste through mechanical recycling (pre-consumer recycle) were used in blends at 10%, 15%, and 20% to produce knitted fabrics. Some performance properties such as fabric stiffness, air permeability, and dimensional change, which are important in the usage properties of jersey knitted fabrics, were compared. Within the scope of the study, the environmental impact of the use of recycled raw materials was evaluated with LCA. According to the Life Cycle Analysis (LCA) results, the use of recycled cotton with contributions ranging from 10% to 20% instead of 100% original cotton demonstrated significant improvements in resource depletion (fossil fuels), global warming, ozone layer depletion, toxic impact on human life, toxic impact on freshwater life, toxic impact on terrestrial life, and total water usage.

Evaluating the Importance of Nitrate‐Containing Aerosols for the Asian Tropopause Aerosol Layer

AbstractThe Asian Summer Monsoon (ASM) convection transports aerosols and their precursors from the boundary layer to the upper troposphere and lower stratosphere (UTLS). This process forms an annually recurring aerosol layer near the tropopause. Recent observations have revealed a distinct property of the aerosol layer over the ASM region, it is nitrate‐rich. We present a newly implemented aerosol formation algorithm that enhances the representation of nitrate aerosol in the Community Aerosol and Radiation Model for Atmospheres (CARMA) coupled with the Community Earth System Model (CESM). The simulated aerosol chemical composition, as well as vertical distributions of aerosol size and mass, are evaluated using in situ and remote sensing observations. The simulated concentrations (ammonium, nitrate, and sulfate) and size distributions are generally within the error bars of data. We find nitrate, organics, and sulfate contribute significantly to the UTLS aerosol concentration between 15°–45°N and 0°–160°E. The two key formation mechanisms of nitrate‐containing aerosols in the ATAL are ammonium neutralization to form ammonium nitrate in regions where convection is active, and condensation of nitric acid in regions of cold temperature. Furthermore, including nitrate formation in the model doubles the surface area density in the tropical tropopause region between 15°–45°N and 0°–160°E, which alters the chlorine partitioning and subsequently impacts the rate of ozone depletion.

Impact Pattern of Energetic Particle Precipitation on Polar Mesospheric Ozone

AbstractThe upper atmosphere of polar regions exhibits two distinct patterns of energetic particle precipitation that can lead to ozone destruction by ionizing the atmosphere: one is the energetic proton precipitation in the polar cap region during solar proton events (SPEs), and the other is the energetic electron precipitations (EEPs) in the auroral oval region from the radiation belt. In this study, we conduct case studies and statistical analyses of ozone observations from the Aura satellite to present the quantitative difference in the impact patterns of SPEs and EEPs on polar mesospheric ozone. According to our statistical analysis of 13 SPEs and 19 EEPs during the MLS time frame, the magnitude of ozone depletion during SPEs is greater than during EEPs. The ozone depletion during SPEs is more pronounced at higher geomagnetic latitudes and negatively correlates with the proton flux, while during EEPs the ozone depletion is more in favor of the geomagnetic latitude band of 60–70° but independent of the electron count rates. In addition, hydroxyl enhancement also exhibits different patterns during SPEs and EEPs, similar to that of ozone depletion. This study further validates the physical link between the magnetosphere and atmosphere and promotes our understanding of the solar influence on Earth's climate.

Whiteness and greenness assessments of a sensitive HPLC method with fluorimetric detection for dapagliflozin quantitation in human plasma: Application to a healthy human volunteer.

The evident ecological impact of human actions, like air pollution, global warming, and ozone depletion, underscores the need for environmentally friendly approaches across various domains, including analytical chemistry. This study aimed to establish a validated, eco-friendly, and sustainable approach utilizing a fluorescence detector coupled with high-performance liquid chromatography for quantifying the antihyperglycemic agent dapagliflozin (DAPA), in human plasma. This method employed a C18 Microsorb MV (4.5 × 250 mm, 5 μm [particle size]) column at 40°C, with 40:60% v/v isocratic elution of acetonitrile and (0.1%) orthophosphoric acid as the mobile phase at 1 mL/min flow rate. DAPA and the internal standard demonstrated their greatest response by performing excitation at 225 nm (λex) and recording chromatograms at an emission wavelength (λem) equal to 305 nm. The presented approach demonstrated high linearity between 50 and 2000 ng/mL and full adherence to the guidelines of the US Food and Drug Administration regarding the validation of bioanalytical methods. The described technique was effectively used for quantification of DAPA in human plasma samples from a healthy male participant who received a tablet of 10 mg DAPA. Analytical Eco-Scale, Analytical GREEnness metric, and the recently created ChlorTox Scale were utilized for greenness assessment. Additionally, the "Red, Green, and Blue 12" model was used in whiteness evaluation.

Thermodynamic Performance Characterization of a Small-Scale Organic Rankine Cycle with 5 kW Net Power Output

Abstract Indonesia’s current energy landscape predominantly depends on fossil fuels and non-renewable energy sources, thereby exacerbating the issue of global warming. On the other side, geothermal utilization in the country still needs to be expanded to reduce the dependency on fossil fuels, particularly through organic Rankine cycle (ORC) systems. As an example, Ulumbu Geothermal Power Plant in Flores Island currently uses a back pressure turbine, which releases expanded steam directly into the atmosphere at 98.7°C and 0.98 bar. This paper presents a thermodynamic analysis of a small-scale Organic Rankine Cycle with 5kW Net power output based on the waste heat data of the Ulumbu Geothermal Power Plant. The study includes selecting the working fluid based on Ozone Depletion Potential (ODP) and Global Warming Potential (GWP) values, thermal efficiency, refrigerant, and steam mass flow rate calculation. Among 20 refrigerants available in Indonesia, R245fa shows promise, offering a Rankine system efficiency of 10-11%, zero ODP, a GWP of 850, and the lowest refrigerant mass flow rate. These parameters inform useful initial parameters for designing a small-scale ORC system producing 5 kW of net power, promoting cleaner and sustainable energy solutions for communities.

Environmental Impact Assessment of a Plant Cell-Based Bio-Manufacturing Process for Producing Plant Natural Product Ingredients

Purpose: This study employed a Life Cycle Assessment (LCA) methodology to evaluate the environmental impacts of a novel plant cell-based biomanufacturing process for producing plant natural product ingredients. The primary purpose was to assess the relative sustainability of the process and to provide insights into potential areas of improvement in the biomanufacturing process. Method: The LCA method used an MS Excel (Ver. 2407) -based approach with a cradle-to-gate system boundary covering raw material sourcing (A1), raw material transportation (A2), and product extract manufacturing (A3) stages. Energy use and material inventory data are presented for different unit operations, and environmental impact factors were obtained from the Ecoinvent database. The study included a Material Circularity Index (MCI) calculation to assess the circularity of the biomanufacturing process for the production of saponin emulsifiers that are normally extracted from the woody tissue of the Chilean soapbark tree (Quillaja saponaria). Comparative analyses were performed against a wild-harvest approach for plant tannin extraction from spruce (Picea abies) tree bark. Key Results: The environmental impact assessment focused on determining relative Global Warming Potential (GWP), Acidification Potential (AP), Freshwater Eutrophication (FE), Particulate Matter Formation (PMF), and Ozone Depletion Potential (ODP). Results indicated that the extract manufacturing stage (A3) contributed significantly to adverse environmental impacts, with varying levels of effects based on the energy source used. Comparative analysis with the wild harvest approach highlights the lower environmental impact of the alternative biomanufacturing process. The biomanufacturing process showed a 23% reduction in GWP, AP, and FE and a 25% reduction in PMF and ODP relative to the wild harvest approach. However, the MCI for the biomanufacturing process was estimated to be 0.186, indicating a low material circularity. Conclusions: The results revealed that the extract manufacturing stage, particularly energy consumption, significantly influences the relative environmental impacts of the alternative production processes. Different energy sources exhibit varying effects, with renewable energy sources showing lower environmental impacts. The Material Circularity Index indicated a low circularity for the biomanufacturing process, suggesting opportunities for improvement, such as incorporating recycled or reused materials. Compared with the tannin extraction process, the plant cell-based biomanufacturing process demonstrated lower environmental impacts, emphasising the importance of sustainable practices and the use of renewable energy sources in future plant natural product sourcing. Recommendations include implementing more sustainable practices, optimising raw material choices, and extending product life spans to enhance circularity and overall environmental benefits.

Influence of quasi-biennial oscillations (QBO) on the stratospheric polar vortex in the Antarctic

For many years, the dominant opinion in the literature has been that the stratospheric polar vortex is weaker in the easterly phase of the QBO than in the westerly phase, which is known as the Holton–Tan effect. While for the Northern Hemisphere vortex this is true during winter, for the Southern Hemisphere vortex the dependence on the QBO is observed only in spring. This feature is usually explained by the greater intensity of the Southern Hemisphere vortex compared to the Northern Hemisphere vortex, and the QBO can modulate its strength only during the vortex breaking season in October-November. Usually, the vortex response to the QBO is determined based on the equatorial wind direction at a certain vertical level, and the conclusions depend strongly on the level at which the QBO phase is determined. However, it has long been shown that using the equatorial wind sign at one or even a combination of several levels is not quite correct because it does not take into account the time of descent of the QBO wind relative to the seasons of the year, and it is not known at what altitudes the QBO wind has the strongest influence on the extratropical stratosphere. Due to the variable period of the QBO cycles, the phase relationship between the seasonal cycle and the QBO cycle is constantly changing, resulting in many variants of the vertical structure of the wind QBO during the Antarctic winter vortex and ozone hole. However, the seasonal regularities of QBO used in this work lead to a strictly limited number of possible variants of coincidence of the phases of the QBO cycles with the seasons of the year, which allows us to reveal typical features of interannual variations of the polar vortex and ozone hole in the Antarctic that are due to the QBO. The analysis of observational data indicates unexpected peculiarities of the QBO modulation of the stratospheric polar vortex in the Antarctic. The QBO effect in the vortex intensity is observed not only in spring during the weakening phase of the winter vortex, but also during the vortex maximum in June–August. At the same time, changes in the wind speed of the vortex during its maximum in winter are opposite to those in the spring during the ozone hole period. If the winter vortex is more intense (weak), then during the ozone hole period the vortex is weaker (more intense) than the average level.