Fant 10282 publikasjoner. Viser side 380 av 412:
2013
2014
2015
2016
2017
Total ozone monitoring from the geostationary orbit : an example using GOES-8 infrared measurements.
2001
Total ozone observations during the past 80 years. Advances in Global Change Research, vol. 33
2008
Total ozone trends at three northern high-latitude stations
After the decrease of ozone-depleting substances (ODSs) as a consequence of the Montreal Protocol, it is still challenging to detect a recovery in the total column amount of ozone (total ozone) at northern high latitudes. To assess regional total ozone changes in the “ozone-recovery” period (2000–2020) at northern high latitudes, this study investigates trends from ground-based total ozone measurements at three stations in Norway (Oslo, Andøya, and Ny-Ålesund). For this purpose, we combine measurements from Brewer spectrophotometers, ground-based UV filter radiometers (GUVs), and a SAOZ (Système d'Analyse par Observation Zénithale) instrument. The Brewer measurements have been extended to work under cloudy conditions using the global irradiance (GI) technique, which is also presented in this study. We derive trends from the combined ground-based time series with the multiple linear regression model from the Long-term Ozone Trends and Uncertainties in the Stratosphere (LOTUS) project. We evaluate various predictors in the regression model and found that tropopause pressure and lower-stratospheric temperature contribute most to ozone variability at the three stations. We report significantly positive annual trends at Andøya (0.9±0.7 % per decade) and Ny-Ålesund (1.5±0.1 % per decade) and no significant annual trend at Oslo (0.1±0.5 % per decade) but significantly positive trends in autumn at all stations. Finally we found positive but insignificant trends of around 3 % per decade in March at all three stations, which may be an indication of Arctic springtime ozone recovery. Our results contribute to a better understanding of regional total ozone trends at northern high latitudes, which is essential to assess how Arctic ozone responds to changes in ODSs and to climate change.
2023
2000
2023
2010
2019
2020
Thousands of per- and polyfluoroalkyl substances (PFAS) exist in the environment and pose a potential health hazard. Suspect and nontarget screening with liquid chromatography (LC)–high-resolution tandem mass spectrometry (HRMS/MS) can be used for comprehensive characterization of PFAS. To date, no automated open source PFAS data analysis software exists to mine these extensive data sets. We introduce FluoroMatch, which automates file conversion, chromatographic peak picking, blank feature filtering, PFAS annotation based on precursor and fragment masses, and annotation ranking. The software library currently contains ∼7 000 PFAS fragmentation patterns based on rules derived from standards and literature, and the software automates a process for users to add additional compounds. The use of intelligent data-acquisition methods (iterative exclusion) nearly doubled the number of annotations. The software application is demonstrated by characterizing PFAS in landfill leachate as well as in leachate foam generated to concentrate the compounds for remediation purposes. FluoroMatch had wide coverage, returning 27 PFAS annotations for landfill leachate samples, explaining 71% of the all-ion fragmentation (CF2)n related fragments. By improving the throughput and coverage of PFAS annotation, FluoroMatch will accelerate the discovery of PFAS posing significant human risk.
2020
Plastic pollution monitoring programs use a wide array of methods, protocols, and analytical approaches, making it difficult for researchers and practitioners to determine which techniques to apply, where, and how. This lack of harmonisation across environmental compartments and plastic size classes has led to inconsistent data and limited comparability across studies. To address this, a systematic review of monitoring methods from 1960 to 2021 was conducted, encompassing both peer-reviewed and grey literature. Techniques were categorised into Reproducible Analytical Pipelines (RAPs), each comprising six core steps: survey design, sample collection, sample preparation, analytical detection, quantification, and data reporting. Each RAP was assessed using Technological Readiness Levels (TRLs) to evaluate maturity and suitability for standardised monitoring. The review revealed that while robust and repeatable methods exist, they are inconsistently applied. At the time of this review, atmospheric plastics was underrepresented, highlighting a critical gap in monitoring efforts. The findings underscore the urgent need for a global, objective framework to guide the selection and implementation of plastic pollution monitoring methodologies. This paper lays the foundation for such a framework by presenting a methodology to identify mature, reproducible methods and prioritise areas for further development. Future work should focus on harmonising protocols across compartments and size classes, improving transparency in data reporting, and building consensus around standardised practices to enable global comparability and policy relevance.
2026
2016