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1.
Sci Total Environ ; 869: 161652, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36693573

RESUMO

The La Palma 2021 volcanic eruption was the first subaerial eruption in a 50-year period in the Canary Islands (Spain), emitting ~1.8 Tg of sulphur dioxide (SO2) into the troposphere over nearly 3 months (19 September-13 December 2021), exceeding the total anthropogenic SO2 emitted from the 27 European Union countries in 2019. We conducted a comprehensive evaluation of the impact of the 2021 volcanic eruption on air quality (SO2, PM10 and PM2.5 concentrations) utilising a multidisciplinary approach, combining ground and satellite-based measurements with height-resolved aerosol and meteorological information. High concentrations of SO2, PM10 and PM2.5 were observed in La Palma (hourly mean SO2 up to ~2600 µg m-3 and also sporadically at ~140 km distance on the island of Tenerife (> 7700 µg m-3) in the free troposphere. PM10 and PM2.5 daily mean concentrations in La Palma peaked at ~380 and 60 µg m-3. Volcanic aerosols and desert dust both impacted the lower troposphere in a similar height range (~ 0-6 km) during the eruption, providing a unique opportunity to study the combined effect of both natural phenomena. The impact of the 2021 volcanic eruption on SO2 and PM concentrations was strongly influenced by the magnitude of the volcanic emissions, the injection height, the vertical stratification of the atmosphere and its seasonal dynamics. Mean daily SO2 concentrations increased during the eruption, from 38 µg m-3 (Phase I) to 92 µg m-3 (Phase II), showing an opposite temporal trend to mean daily SO2 emissions, which decreased from 34 kt (Phase I) to 7 kt (Phase II). The results of this study are relevant for emergency preparedness in all international areas at risk of volcanic eruptions; a multidisciplinary approach is key to understand the processes by which volcanic eruptions affect air quality and to mitigate and minimise impacts on the population.

2.
Geophys Res Lett ; 48(5): e2020GL091987, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33785974

RESUMO

Throughout spring and summer 2020, ozone stations in the northern extratropics recorded unusually low ozone in the free troposphere. From April to August, and from 1 to 8 kilometers altitude, ozone was on average 7% (≈4 nmol/mol) below the 2000-2020 climatological mean. Such low ozone, over several months, and at so many stations, has not been observed in any previous year since at least 2000. Atmospheric composition analyses from the Copernicus Atmosphere Monitoring Service and simulations from the NASA GMI model indicate that the large 2020 springtime ozone depletion in the Arctic stratosphere contributed less than one-quarter of the observed tropospheric anomaly. The observed anomaly is consistent with recent chemistry-climate model simulations, which assume emissions reductions similar to those caused by the COVID-19 crisis. COVID-19 related emissions reductions appear to be the major cause for the observed reduced free tropospheric ozone in 2020.

3.
Sci Data ; 6: 180302, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30667381

RESUMO

The isotopic composition of water vapour provides integrated perspectives on the hydrological histories of air masses and has been widely used for tracing physical processes in hydrological and climatic studies. Over the last two decades, the infrared laser spectroscopy technique has been used to measure the isotopic composition of water vapour near the Earth's surface. Here, we have assembled a global database of high temporal resolution stable water vapour isotope ratios (δ18O and δD) observed using this measurement technique. As of March 2018, the database includes data collected at 35 sites in 15 Köppen climate zones from the years 2004 to 2017. The key variables in each dataset are hourly values of δ18O and δD in atmospheric water vapour. To support interpretation of the isotopologue data, synchronized time series of standard meteorological variables from in situ observations and ERA5 reanalyses are also provided. This database is intended to serve as a centralized platform allowing researchers to share their vapour isotope datasets, thus facilitating investigations that transcend disciplinary and geographic boundaries.

4.
Rev. Soc. Méd.-Quir. Hosp. Emerg. Pérez de León ; 24(1): 89-103, mar. 1989. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-73855

RESUMO

En un estudio comparativo del peso y talla entre 196 mujeres normales y 56 pacientes con carcinoma mamario. Se pudo establecer en la paciente post-menopáusica un sobrepeso de alrededor del 15%. Y no se encontró sobrepeso en las pacientes con enfermedad mamaria benigna. La edad de la menarquia fue 1,2 años más tardía en las pacientes que en los controles. El primer embarazo fue 2,5 años más tardío en las pacientes con patología maligna en comparación con las pacientes con patología y con los controles. Los valores de colesterol sanguineo estuvieron por encima de lo normal en las pacientes pre-menopáusicas con ambas patologías. Las pre-menopáusicas con enfermedad benigna presentaron cifras ligeramente bajas, y valores normales en los casos de patología maligna. Las dos patologias en la mujer pre-menopáusica presentaron valores elevados de triglicéridos y muy bajos en la post-menopáusica. Se encontro un aumento de la VLDL en las pacientes con patología benigna, siendo mayor en esta última. El índice LDL/VLDL fue menor que el índice normal en las pacientes con enfermedad maligna y parece disminuir con el progreso de la enfermedad


Assuntos
Adulto , Pessoa de Meia-Idade , Humanos , Feminino , Neoplasias da Mama , Neoplasias da Mama/patologia , Colesterol , Lipoproteínas , Triglicerídeos
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