149 research outputs found

    Multiple symptoms of total ozone recovery inside the Antarctic vortex during austral spring

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    The long-term evolution of total ozone column inside the Antarctic polar vortex is investigated over the 1980-2016 period. Trend analyses are performed using a multilinear regression (MLR) model based on various proxies (heat flux, QBO, solar flux, AAO and aerosols). Annual total ozone column corresponding to the mean monthly values inside the vortex in September and during the period of maximum ozone depletion from September 15th to October 15th are used. Total ozone columns from combined TOMS-N7, SBUV-N9, TOMS-EP and OMI-TOMS satellite datasets and the Multi-Sensor Reanalysis (MRS-2) dataset are considered in the study. Ozone trends are computed by a piecewise trend model (PWT) before and after the turnaround in 2001. In order to evaluate total ozone within the vortex, two classification methods are used, based on the potential vorticity gradient as a function of equivalent latitude. The first standard one, considers this gradient at a single isentropic level (475K or 550K), while the second one uses a range of isentropic levels between 400K and 600K. The regression model includes a new proxy that represents the stability of the vortex during the studied month period. The determination coefficient (R2) between observations and modeled values increases by ~0.05 when this proxy is included in the MLR model. The higher R2 (0.93-0.95) and the minimum residuals are found for the second classification method in the case of both datasets and months periods. Trends in September are statistically significant at 2 sigma level with values ranging between 1.85 and 2.67 DU yr-1 depending on the methods and data sets. This result confirms the recent studies of Antarctic ozone healing during that month. Trends after 2001 are 2 to 3 times lower than before the turnaround year as expected from the response to the slowly ODS decrease in Polar regions.Estimated trends in the 15Sept-15Oct period are smaller than in September. They vary from 1.15 to 1.78 DU yr-1 and are hardly significant at 2 level. Ozone recovery is also confirmed by a steady decrease of the relative area of total ozone values lower than 150 DU within the vortex in the 15Sept-15Oct period since 2010. Comparison of the evolution of the ozone hole area in September and October show a decrease in September, confirming the later formation of the ozone hole during that month.Fil: Pazmino, Andrea. Universidad Paris Saclay; FranciaFil: Godin Beekmann, Sophie. Universidad Paris Saclay; FranciaFil: Hauchecorne, Alain. Universidad Paris Saclay; FranciaFil: Claud, Chantal. Ecole Polytechnique; FranciaFil: Khaykin, Sergey. Universidad Paris Saclay; FranciaFil: Goutail, Florence. Universidad Paris Saclay; FranciaFil: Wolfram, Elian Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; Argentina. Ministerio de Defensa; ArgentinaFil: Salvador, Jacobo Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; Argentina. Ministerio de Defensa; Argentina. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentina. Universidad Nacional de la Patagonia Austral; ArgentinaFil: Quel, Eduardo Jaime. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; Argentina. Ministerio de Defensa; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; Argentin

    Detección serológica del Virus Papiloma Humano en mujeres mayores de 20 años. Caso sector “Gary Esparza”, Babahoyo, Ecuador // Serological detection of human papilloma virus in women over 20 years. “Gary Esparza” sector, Babahoyo, Ecuador

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    El Virus del Papiloma Humano (HPV) tiene un genoma ADN bicatenario perteneciente a la familia de los Papovaviridae, tiene capacidad oncogénica en una variedad de mamíferos, en especial el hombre, en el que se conoce más de 200 serotipos y representa una de las enfermedades de transmisión sexual más común, por su relación de patogenia oncológica. Se clasifica en tipos de alto y bajo riesgo oncológico (IARC), también se ha descrito otros tipos de infecciones como las orofaríngeas y amigdalitis. El objetivo de este estudio fue determinar el cribado de detección de anticuerpos IgG contra los genotipos 6, 11, 16 y 18 del virus mencionado, mediante la técnica serológica de Microelisa. Mediante un estudio descriptivo, prospectivo y transversal, realizado en el primer semestre del año 2015 en el Sector Gary Esparza del cantón Babahoyo, provincia de Los Ríos, Ecuador, de un universo de 250 habitantes se tomaron muestras sanguíneas a 97 mujeres mayores de 20 años y determinó 8 casos positivos (8.25%), con ello se estableció el primer diagnóstico serológico en el país, lo que constituye una herramienta de detección preliminar o screening de un gran número de muestras. ABSTRACT The Human Papilloma Virus (HPV) is a virus that has a double-stranded DNA genome belonging to the Papovaviridae family. It has oncogenic ability in a variety of mammals, especially man, in which more than 200 serotypes are known and represents one of the most common sexually transmitted diseases because of its relation to oncological pathogenesis.  It is classified into high and low cancer types (IARC), other types of infections such as oropharyngeal and tonsillitis have also been described. The objective of this study was to determine the screening of IgG antibodies against Human Papilloma Virus genotypes 6, 11, 16 and 18 using the Microelisa serological technique. A descriptive, prospective and cross-sectional study was carried out during the first semester of 2015 in the Gary Esparza Sector of Babahoyo, Los Ríos province, with a population of 250 habitants. Blood samples were taken from 97 women with 20 years old, being determined 8 positive cases (8.25%), establishing the first serological diagnosis in the country, which is a tool for preliminary screening or screening of a large number of samples

    The unusual persistence of an ozone hole over a southern mid-latitude station during the Antarctic spring 2009: a multi-instrument study

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    International audienceRecord-low ozone column densities (with a minimum of 212 DU) persisted over three weeks at the Río Gallegos NDACC (Network for the Detection of Atmospheric Composition Change) station (51.5° S, 69.3° W) in November 2009. Total ozone remained two standard deviations below the climatological mean for five consecutive days during this period. The statistical analysis of 30 years of satellite data from the Multi Sensor Reanalysis (MSR) database for Río Gallegos revealed that such a long-lasting low-ozone episode is a rare occurrence. The event is examined using height-resolved ozone lidar measurements at Río Gallegos, and observations from satellite and ground-based instruments. The computed relative difference between the measured total ozone and the climatological monthly mean shows reductions varying between 10 and 30% with an average decrease of 25%. The mean absolute difference of total ozone column with respect to climatological monthly mean ozone column is around 75 DU. Extreme values of the UV index (UVI) were measured at the ground for this period, with the daily maximum UVI of around 13 on 15 and 28 November. The high-resolution MIMOSA-CHIM (Modélisation Isentrope du transport Méso-échelle de l'Ozone Stratosphérique par Advection) model was used to interpret the ozone depletion event. An ozone decrease of about 2 ppmv was observed in mid-November at the 550 K isentropic level (~22 km). The position of Río Gallegos relative to the polar vortex was classified using equivalent latitude maps. During the second week of November, the vortex was over the station at all isentropic levels, but after 20 November and until the end of the month, only the 10 lower levels in the stratosphere were affected by vortex overpasses with ozone poor air masses. A rapid recovery of the ozone column density was observed later, due to an ozone rich filament moving over Río Gallegos between 18 and 24 km in the first two weeks of December 2009

    Almost one year of TROPOMI/S5P total ozone column data: global ground-based validation

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    Póster presentado en: ATMOS 2018, celebrado en Salzburgo (Austria) del 26 al 29 de noviembre de 2018.In this work we present the validation results of almost one year of TROPOMI Near Real Time (NRTI) and OFFLine (OFFL) data against ground-based quality-assured Brewer and Dobson total ozone column (TOC) measurements deposited in the World Ozone and Ultraviolet Radiation Data Center (WOUDC). Additionally, comparisons to Brewer measurements from the European Brewer Network (EUBREWNET) and the Canadian Network are performed, as well as to twilight zenith-sky measurements obtained with ZSL-DOAS (Zenith Scattered Light Differential Optical Absorption Spectroscopy) instruments, that form part of the SAOZ network (Système d'Analyse par Observation Zénitale) of the Network for the Detection of Atmospheric Composition Change (NDACC). Through the comparison of the TROPOMI measurements to the total ozone ground-based measurements from stations that are distributed globally, as the background truth, the dependence of the new instrument on latitude, cloud properties, solar zenith and viewing angles, among others, is examined. Validation results show that the mean bias and the standard deviation of the percentage difference between TROPOMI and QA ground TOC meet the product requirements

    TROPOMI/S5P total ozone column data: global ground-based validation and consistency with other satellite missions

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    In this work, the TROPOMI near real time (NRTI) and offline (OFFL) total ozone column (TOC) products are presented and compared to daily ground-based quality-assured Brewer and Dobson TOC measurements deposited in the World Ozone and Ultraviolet Radiation Data Centre (WOUDC). Additional comparisons to individual Brewer measurements from the Canadian Brewer Network and the European Brewer Network (Eubrewnet) are performed. Furthermore, twilight zenith-sky measurements obtained with ZSL-DOAS (Zenith Scattered Light Differential Optical Absorption Spectroscopy) instruments, which form part of the SAOZ network (Système d'Analyse par Observation Zénitale), are used for the validation. The quality of the TROPOMI TOC data is evaluated in terms of the influence of location, solar zenith angle, viewing angle, season, effective temperature, surface albedo and clouds. For this purpose, globally distributed ground-based measurements have been utilized as the background truth. The overall statistical analysis of the global comparison shows that the mean bias and the mean standard deviation of the percentage difference between TROPOMI and ground-based TOC is within 0 –1.5 % and 2.5 %–4.5 %, respectively. The mean bias that results from the comparisons is well within the S5P product requirements, while the mean standard deviation is very close to those limits, especially considering that the statistics shown here originate both from the satellite and the ground-based measurements.This research has been supported by the European Space Agency “Preparation and Operations of the Mission Performance Centre (MPC) for the Copernicus Sentinel-5 Precursor Satellite” (contract no. 4000117151/16/1-LG)

    Precision gestational diabetes treatment: a systematic review and meta-analyses

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    Genotype-stratified treatment for monogenic insulin resistance: a systematic review

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    DIAL lidar for ozone measurements

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    This chapter presents a general overview of ground-based lidar system for ozone measurements in the troposphere as well as in the stratosphere. The DIAL technique, generally used by the lidar teams for ozone measurements is explained. Afterwards, the different elements of the DIAL system are assessed in this work. Finally, a brief description of the ozone DIAL systems for different altitudes ranges operated at the Haute Provence Observatory (OHP) in Southern France as well as some scientist results are showed

    Etude de l'influence de la perte chimique d'ozone antarctique sur la région subpolaire de l'hémisphère sud et relation avec le rayonnement ultraviolet

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    PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

    Signatures of the Antarctic ozone loss saturation in the late 1980s

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    The chemical ozone loss in the Antarctic due to increased halogen loading was first noticed in the late 1970s and early 1980s. Intense monitoring of the processes by various measurement clusters has been initiated since then, including ozone soundings at a number of Antarctic stations in each winter and spring. We examine the ozone measurements taken by the sondes from a group of stations in the continent to analyse the progress, saturation and anticipated decrease of the ozone depletion in the Antarctic. The analysis of the data reveals that, in agreement with available records, the ozone loss in the region intensified by the mid 1980s. The saturation of ozone loss has, however, shown to be started by 1987 in contrast to previously published results. The signatures of saturation are clearly evident at a range of lower stratospheric isentropic levels between 350 and 500 K in October. In September, the saturation is observed from 1991 onwards. The diagnosis is performed on a potential temperature equivalent latitude (EqL) surface to distinguish the dependency of loss saturation on EqL. The study shows that the saturation has taken place irrespective of EqL over the years in the range of 65-90 EqL covered by the ozone soundings; i.e. above the 65 degree EqL cut off used in this study. While the saturation of ozone depletion continues until now, the average ozone values inside the vortex show a clear levelling off after 1996. The regression of vortex averaged ozone against Equivalent Effective Stratospheric Chlorine for the 1997-2010 period corroborates the levelling off of ozone depletion. It also suggests that the complete recovery of ozone layer in the Antarctic is still a few decades away
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