Found 10488 publications. Showing page 420 of 420:
2026
Ozone responses to the geomagnetic storms in 2024 and 2025
Solar Cycle 25 has approached its maximum phase, bringing an elevated frequency of solar eruptive events and associated geomagnetic disturbances. During 2024 and 2025, several intense geomagnetic storms have provided rare opportunities to examine the short-term coupling between space‐weather forcing and the middle atmosphere. Previous studies have shown that energetic particle precipitation (EPP) during geomagnetic storms can substantially modify the chemical composition of the mesosphere and lower thermosphere (MLT), particularly through the production of odd nitrogen (NOx) and odd hydrogen (HOx), which catalytically destroy ozone. In this presentation, we investigate the MLT ozone responses to several large geomagnetic storms occurring in 2024–2025 using MLS satellite observation. We will also estimate the particle forcing associated with these events using the observed ozone chemical responses. This analysis provides a testbed for climate model inputs.
2026
2026
Abstract Trifluoroacetic acid (TFA) is a persistent pollutant with potential long‐term effects on the environment and on health. Recent studies using ice core records report large increases (up to tenfold) in Arctic TFA deposition since the 1970s, and trends suggest long‐lived chlorofluorocarbon (CFC) replacements may be a major source. Here, we use a chemical transport model to examine the global TFA budget arising from CFC replacements–hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs)–and inhalation anesthetics. Global TFA deposition from these sources increased ∼3.5‐fold from 6.8 (5.9–7.6) Gg/yr in 2000 to 21.8 (18.6–25.0) Gg/yr in 2022, with cumulative deposition reaching 335.5 Gg. We find HCFC‐123, HCFC‐124, and HFC‐134a account for most modeled TFA production and that long‐lived CFC replacements account for virtually all of the observed Arctic deposition trend. At lower latitudes, our analysis supports the recent emergence of hydrofluoroolefins (HFOs) as a TFA source. We conclude that increased TFA monitoring is required.
2026
Safeguarding drinking water in north-western europe by modelling the fate of amines from CO2capture
The European Union (EU) net-zero emission target for 2050 requires large-scale deployment of carbon capture and storage (CCS). Amine-based CO2 capture (CC) is the most mature CC technology but may lead to the spread of nitrosamines (NSAs) and nitramines (NAs) in the nearby surroundings. These are carcinogenic compounds that can persist in water resources. Hence, EU's ambition towards carbon neutrality might pose risk of drinking water contamination as well as ecosystem and agricultural crops pollution. We compiled a dataset of planned CCS projects in the Franco-Danish corridor, Europe's future CCS hub, where most capacity will be located by 2030, with at least 40% based on amine technology. Spatial analysis indicates that up to 10.2 million inhabitants, large Natura 2000 reserves, and extensive crop areas may be impacted by NA and NSA deposition, often in regions already under severe water stress. Biogeochemical modelling shows that surface waters with short residence times are highly sensitive to deposition rates, whereas groundwater concentrations depend strongly on the interplay between NA and NSA half-lives and travel times, creating greater uncertainty in aquifers, especially small systems with limited dilution. In both cases, MEA is the most environmentally friendly when emission abatement measures are limited to water wash, compared to piperazine and other emerging solvents. Main findings highlight the need for regional-scale modelling and harmonized regulation to safeguard drinking water, ecosystems, and food security as CCS deployment expands.
2026
Plastic pellet spills are a major source of microplastic pollution, and pellets are found on beaches worldwide. However, the potential environmental impacts of these spills remain poorly understood. In December 2023, approximately 25,000 kg of polyethylene pellets containing high concentrations of the additive Tinuvin UV-622 were spilled during a shipping accident off the northern coast of Portugal. Pellets collected from an affected beach located in Galicia, Spain, along with solvent extracts and aqueous leachates, were subjected to both target and nontarget chemical analyses and tested in a battery of toxicity assays including a green microalga (Raphidocelis subcapitata), a marine copepod (Apocyclops royi), a fish model (Danio rerio), and a human cell line. Chemical screening identified on the order of 50 chemical substances in addition to Tinuvin UV-622, including a range of known plastic additives and nonintentionally added substances (NIAS). Toxicity assays revealed significant growth inhibition and stress-induced cell aggregation in R. subcapitata and acute toxicity causing immobilization in copepods, which could have potential implications in the environment via the disruption of primary producers and food web dynamics. In contrast, zebrafish embryos showed no significant developmental effects, while human cells exhibited modest, time-dependent reductions in viability. Our findings underscore the complex chemical burden associated with pellet spills and stress the need for policies and regulations to prevent them, reinforcing the importance of applying the precautionary principle in managing the environmental risks linked to plastic pellet production, transport, and accidental release.
2026
The growing adoption of low-cost sensors (LCSs) has significantly enhanced environmental monitoring by enabling widespread, community-driven data collection, particularly in regions requiring dense monitoring, and in regions with limited or no reference instrumentation. Increased public awareness and demand for dense environmental monitoring have resulted in extensive air quality and meteorological datasets from diverse sources. However, the integration of such datasets into regulatory frameworks and large-scale environmental monitoring remains challenging due to persistent issues related to data quality, standardization, and interoperability. To address these challenges, the FILTER (Framework for Improving Low-cost Technology Effectiveness and Reliability) approach developed by Hassani et al. (2025) provides a suite of algorithms to harmonize, quality-check, flag, and perform in-situ corrections on crowdsourced PM2.5 LCS datasets. While FILTER was initially designed and validated for static PM2.5 sensors, it has since been extended to address data quality challenges associated with the dynamics of mobile and wearable sensing. Across both static and mobile LCS platforms, FILTER employs a unified processing pipeline that generates measurement-level quality flags based on multiple statistical tests, to quantify the reliability of each observation. Quality control (QC) includes statistical tests to: (a) assess physical measurement consistency (range validity test), (b) detect flatline behavior (constant value test), and (c) identify abnormal patterns (spatiotemporal outlier detection test) using both historical trends and spatial comparisons with neighboring LCSs. Beyond these mandatory QC steps, more advanced statistical procedures incorporate relative (spatial correlation test) and absolute (spatial similarity test) comparisons with nearby LCSs, higher-quality instruments, and reference monitoring stations. For mobile and wearable sensing, FILTER has been specifically adapted to support pairwise comparisons between mobile sensors and comparisons with higher-accuracy nodes, accounting for operation under dynamic environmental and operational conditions. In this context, statistical comparisons are evaluated during rendezvous events, that is, periods in which the mobile sensor and a higher-accuracy node provide temporally coincident measurements. The modified framework retains the core principles of transparency, scalability, and sensor independence, while introducing additional steps to address motion-related artifacts, intermittent time series, and location-specific uncertainties. FILTER is developed in the open-source R environment. Its modular and hierarchical design allows flexible adaptation of quality control and correction workflows based on data availability, the spatiotemporal characteristics of LCS networks, and application-specific requirements. By improving data reliability and usability, FILTER enables crowdsourced LCS datasets to serve as a reliable complement to official monitoring networks for air quality management, urban- and regional-scale modeling, and policymaking. References Hassani, A., Salamalikis, V., Schneider, P., Stebel, K., and Castell, N.: A scalable framework for harmonizing, standardization, and correcting crowd-sourced low-cost sensor PM2. 5 data across Europe, J. Environ. Manage., 380, 125100, 2025.
2026
Benzotriazole UV stabilizers (BUVs) are widely used plastic additives and are increasingly recognized as contaminants of emerging concern due to their persistence and potential for long-range environmental transport. In this study, bird feathers collected from polar regions and China were analyzed to investigate the occurrence and profiles of BUVs. BUVs were detected in all studied regions, with detection frequencies varying among compounds (up to 89.2%) and concentration levels ranging from 9.64 to 52.68 ng/g ww for ΣBUVs. Among individual compounds, UV-329 exhibited the highest median concentration (up to 26.0 ng/g ww), followed by UV-326 and UV-327. BUVs were identified in Antarctic bird feathers, whereas previous biomonitoring studies based on other biological matrices reported non-detectable levels in Antarctic samples. This work also represents the first application of bird feathers to investigate BUV contamination across the Arctic, the Antarctic, and China. Differences in BUV profiles were observed across regions and species, but these patterns should be interpreted cautiously because sampling year, species ecology, and feather-specific processes may all influence feather concentrations. The results also support the use of bird feathers as a non-destructive biomonitoring matrix for monitoring BUV contamination in both remote and populated regions. These findings highlight the need for further investigation into the sources, transport pathways, and ecological risks of BUVs.
2026
2026