25 research outputs found

    Unsupervised method to classify PM10 pollutant concentrations

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    In this paper a method based mainly on Data Fusion and Artificial Neural Networks to classify one of the most important pollutants such as Particulate Matter less than 10 micrometer in diameter (PM10) concentrations is proposed. The main objective is to classify in two pollution levels (Non-Contingency and Contingency) the pollutant concentration. Pollutant concentrations and meteorological variables have been considered in order to build a Representative Vector (RV) of pollution. RV is used to train an Artificial Neural Network in order to classify pollutant events determined by meteorological variables. In the experiments, real time series gathered from the Automatic Environmental Monitoring Network (AEMN) in Salamanca Guanajuato Mexico have been used. The method can help to establish a better air quality monitoring methodology that is essential for assessing the effectiveness of imposed pollution controls, strategies, and facilitate the pollutants reduction

    HTAP3 fires: towards a multi-model, multi-pollutant study of fire impacts

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    Open biomass burning has major impacts globally and regionally on atmospheric composition. Fire emissions include particulate matter, tropospheric ozone precursors, greenhouse gases, as well as persistent organic pollutants, mercury and other metals. Fire frequency, intensity, duration, and location are changing as the climate warms, and modelling these fires and their impacts is becoming more and more critical to inform climate adaptation and mitigation, as well as land management. Indeed, the air pollution from fires can reverse the progress made by emission controls on industry and transportation. At the same time, nearly all aspects of fire modelling – such as emissions, plume injection height, long-range transport, and plume chemistry – are highly uncertain. This paper outlines a multi-model, multi-pollutant, multi-regional study to improve the understanding of the uncertainties and variability in fire atmospheric science, models, and fires’ impacts, in addition to providing quantitative estimates of the air pollution and radiative impacts of biomass burning. Coordinated under the auspices of the Task Force on Hemispheric Transport of Air Pollution, the international atmospheric modelling and fire science communities are working towards the common goal of improving global fire modelling and using this multi-model experiment to provide estimates of fire pollution for impact studies. This paper outlines the research needs, opportunities, and options for the fire-focused multi-model experiments and provides guidance for these modelling experiments, outputs, and analysis that are to be pursued over the next 3 to 5 years. It proposes a plan for delivering specific products at key points over this period to meet important milestones relevant to science and policy audiences

    Saharan air outflow variability in the 1980–2020 period

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    8 pags., 6 figs.Airborne dust represents a hazard to the environment and human health. The outflow of air masses carrying dust from northern Africa, the world's largest active dust source, to the North Atlantic and Mediterranean regions is modulated by atmospheric conditions. However, how global warming-driven changes on atmospheric circulation have influenced North African air outflow in the recent past is not well understood. Here, we explore the Saharan air outflow from northwestern Africa over the 1980 to 2020 period. We find a decrease in the transport to the Atlantic Ocean and the Iberian Peninsula of −0.29 ± 0.16% dec and -0.66 ± 0.18% dec, respectively, and an increasing trend to the Mediterranean Sea (0.24 ± 0.18% dec) and Europe (0.60 ± 0.18% dec). The results indicate that the strengthening of the Atlantic high pressure system and the Saharan thermal low, both associated with the narrowing of the Intertropical Convergence Zone and the Hadley Cell expansion under global warming, could be favoring the Saharan outflow to the Mediterranean Sea and Europe in detriment of transport to the Atlantic Ocean. The results also show that present-day Saharan air arrives at these regions at higher altitudes and in shorter timescales than decades ago. This is associated to the increase in surface heating conditions in the Sahara, 0.41 ± 0.02 °C dec, that can inject air into windier upper atmospheric levels, thereby allowing higher and faster air transport. Our results suggest a change in the Saharan air outflow likely associated with global warming and with potentially significant implications for the temporal and spatial patterns of North African dust export.The authors thank the Copernicus Climate Data Store (C3S) and ECMWF (European Centre for Medium-Range Weather Forecasts) for the ERA5 meteorological fields. Thanks also to the National Oceanic and Atmospheric Administration (NOAA) Air Resources Laboratory (ARL) for the provision of the HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) mode

    Efficacy of Laser Resurfacing and Facial Plastic Surgery Using Age, Glogau, and Fitzpatrick Rating

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    Background:. To assess clinical outcomes based on established rating scales in patients who underwent treatment for rhytids using laser resurfacing with and without facial plastic surgery. Methods:. Retrospective case review of 48 patients treated by the senior author (J.E.B) between 2009 and 2016. Three reviewers assigned ratings to a total of 48 patients using estimated age and Fitzpatrick, Modified Fitzpatrick, and Glogau scales. Reviewers were blinded to patient demographics and before and after photographs. Patients elected to receive laser-only treatment or combination laser plus facial plastic surgery. Participants included forty-eight patients were selected on the basis that they had either laser treatment alone or laser plus facial plastic surgery and pre- and postoperative photographs. Results:. Patients with higher Fitzpatrick scores had a greater reduction in Glogau score (ß = 1.66; SE = 0.59; P < 0.01). With respect to modified Fitzpatrick scores after surgery, patients with higher Glogau scores of 3 or 4 before surgery (P < 0.01) had higher scores after surgery ((ß = 0.07; SE = 0.02; P < 0.01). For estimated age, the average change was -1.7 years after laser resurfacing (P = 0.038; 95% CI, 2.96–3.06 years) and -2.07 years when combined with surgery (P = 0.01; 95% CI, 2.89–3.19 years). Conclusions:. Patients with Fitzpatrick scores of 3, 4, 5, younger patients, and those with less rhytids before surgery tended to have lower Glogau scores after surgery. These findings provide insight on an approach to treating ethnic skin and aging face concerns
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