Search results for "wind"
showing 10 items of 846 documents
Fast tracking of wind speed with a differential absorption LiDAR system: First results of an experimental campaign at Stromboli volcano
2017
Carbon dioxide ( CO 2 ) is considered a precursor gas of volcanic eruptions by volcanologists. Monitoring the anomalous release of this parameter, we can retrieve useful information for the mitigation of volcanic hazards, such as for air traffic security. From a dataset collected during the Stromboli volcano field campaign, an assessment of the wind speed, in both horizontal and vertical paths, performing a fast tracking of this parameter was retrieved. This was determined with a newly designed shot-per-shot differential absorption LiDAR system operated in the near-infrared spectral region due to the simultaneous reconstruction of CO 2 concentrations and wind speeds, using the same sample o…
A new approach for the measurement of gaseous elemental mercury (GEM) and H2S in air from anthropogenic and natural sources: Examples from Mt. Amiata…
2017
Real-time measurements of GEM and H2S discharged from natural and anthropogenic sources are a valuable tool to investigate the dispersion dynamics of these contaminants in air. In this study, a new approach to measure GEM and H2S concentrations in air, carried out by coupling a portable Zeeman atomic absorption spectrometer with high frequency modulation of light polarization (Lumex RA-915M) and a pulsed fluorescence gas analyzer (Thermo Scientific Model 450i), was applied to two distinct areas: (i) in the surroundings of Piancastagnaio (Siena, Central Italy), located in the eastern flanks of Mt. Amiata (a 200,000Â years old volcano), where three geothermal plants are operating and whose ex…
Measuring SO2 Emission Rates at Kīlauea Volcano, Hawaii, Using an Array of Upward-Looking UV Spectrometers, 2014–2017
2018
Retrieving accurate volcanic sulfur dioxide (SO2) gas emission rates is important for a variety of purposes. It is an indicator of shallow subsurface magma, and thus may signal impending eruption or unrest. SO2 emission rates are significant for accurately assessing climate impact, and providing context for assessing environmental, agricultural, and human health effects during volcanic eruptions. The U.S. Geological Survey Hawaiian Volcano Observatory uses an array of ten fixed, upward-looking ultraviolet spectrometer systems to measure SO2 emission rates at 10-s sample intervals from the Kīlauea summit. We present Kīlauea SO2 emission rates from the volcano’s summit and middle East Rift Zo…
First-time lidar measurement of water vapor flux in a volcanic plume
2011
Abstract The CO 2 laser-based lidar ATLAS has been used to study the Stromboli volcano plume. ATLAS measured water vapor concentration in cross-sections of the plume and wind speed at the crater. Water vapor concentration and wind speed were retrieved by differential absorption lidar and correlation technique, respectively. Lidar returns were obtained up to a range of 3 km. The spatial resolution was 15 m and the temporal resolution was 20 s. By combining these measurements, the water vapor flux in the Stromboli volcano plume was found. To our knowledge, it is the first time that lidar retrieves water vapor concentrations in a volcanic plume.
Accurate measurement of volcanic SO2flux: Determination of plume transport speed and integrated SO2concentration with a single device
2005
[1] Ground-based measurements of volcanic sulfur dioxide fluxes are important indicators of volcanic activity, with application in hazard assessment, and understanding the impacts of volcanic emissions upon the environment and climate. These data are obtained by making traverses underneath the volcanic plume a few kilometers from source with an ultraviolet spectrometer, measuring integrated SO2 concentrations across the plume's cross section, and multiplying by the plume's transport speed. However, plume velocities are usually derived from ground-based anemometers, located many kilometers from the traverse route and hundreds of meters below plume altitude, complicating the experimental desi…
Alternative energy scenarios for small islands: A case study from Salina Island (Aeolian Islands, Southern Italy)
2012
Abstract The Aeolian archipelago is made up of seven main islands situated in the Tyrrhenian sea (Sicily Italy). They represent a suitable scenario for the development of a sustainable energy production system, that could easily be reproduced on other Mediterranean Islands. The fact that these islands depend on the mainland for energy supplies and the high cost of bringing fuel in tanker boats are factors that should strongly encourage the use of renewable energy source technologies. Taking into account the European Commission guidelines, this paper sets out to evaluate potential energy production using photovoltaic and small scale wind power, in order to verify their contribution to overal…
Up-wind difference approximation and singularity formation for a slow erosion model
2020
We consider a model for a granular flow in the slow erosion limit introduced in [31]. We propose an up-wind numerical scheme for this problem and show that the approximate solutions generated by the scheme converge to the unique entropy solution. Numerical examples are also presented showing the reliability of the scheme. We study also the finite time singularity formation for the model with the singularity tracking method, and we characterize the singularities as shocks in the solution.
Europe 2020: analisi multidimensionale a livello macro e micro per il confronto e il monitoraggio nel settore delle rinnovabili
Obiettivo generale del presente lavoro è proporre analisi statistiche di tipo multidimensionale finalizzate a valutare e monitorare gli effetti delle politiche Europee nel settore delle Fonti di Energia Rinnovabile (FER), con un focus specifico al monitoraggio della Europe2020 a livello regionale. La prima parte del lavoro presenta un panoramica storica dei principali atti legislativi con i quali è stata avviata concretamente la Politica Energetica sulle rinnovabili a livello Europeo. Alla luce delle informazioni così raccolte, la seconda parte della tesi ha avuto ad oggetto l’analisi dell’effetto, misurato in termini di Mega Watt installati, dei regimi di sostegno implementati da 11 Stati …
Inkasācijas sistēmas uzlabošana
2017
Kvalifikācijas darba ietvaros tika veikta inkasācijas sistēmas pārrakstīšana, saglabājot esošo funkcionalitāti. Sistēma sastāv no 2 komponentēm: servera puses lietotne, kur tiek glabāta visu inkasentu dati un Windows CE portatīvā datu termināļa puses lietotne, kurā inkasents ievada datus un sinhronizē tos ar serveri. Termināļa puses lietotne, izmantojot React izstrādes ietvaru, tika pārrakstīta mobilajām ierīcēm. Šī darba mērķis ir: pārrakstīt esošo termināļa lietotni mobilajām ierīcēm (Android, iOS) atjaunot novecojušu programmatūru ieekonomēt līdzekļus, inkasācijai izmantojot darbiniekiem izdotos viedtālruņus Jaunā lietotne viedtālruņos nodrošinās iespēju sinhronizēt datus ar serveri, ske…
Effect of weather conditions on somatic cell score in Sicilian Valle del Belice ewes
2010
Mastitis susceptibility of Valle del Belice ewes from the south of Sicily to temperature, humidity, precipitation, solar radiation, sun hours, air pressure, wind-speed and wind-direction measured by a public weather station was investigated using 65,848 test-day somatic cell score (SCS) records of 5,237 ewes. All weather parameters had an effect on SCS in a regression approach. Extreme values of maximum and minimum temperaturehumidity indices resulted in increased SCS. Higher precipitation, solar radiation and sun hours resulted in increased SCS, whereas higher air pressure and wind speed resulted in reduced SCS.