Search results for "luxe"
showing 10 items of 80 documents
Volcanic CO2 measurements at Campi Flegrei by Infrared Tunable Diode Laser absorption Spectroscopy
2014
Gas studies add information for the interpretation of fluid circulation dynamics at dormant volcanoes and can contribute to eruption forecasting. Direct in-situ and remote-sensing techniques were used in order to improve volcanic gas monitoring, essential for hazard assessment. In the last decades, near-infrared diode lasers have increasingly been used in atmospheric research and, though in an experimental phase, are now finding applications in volcanic gas studies. The Tunable Diode Laser Spectroscopy technique (TDLS) relies on measuring the absorbance at specific wavelengths due to the absorption of IR radiation by a target gas. Here, we report on the application of the GasFinder 2.0, an …
Statistical upscaling of ecosystem CO2 fluxes across the terrestrial tundra and boreal domain: Regional patterns and uncertainties
2021
The regional variability in tundra and boreal carbon dioxide (CO2) fluxes can be high, complicating efforts to quantify sink-source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we compile eddy covariance and chamber measurements of annual and growing season CO2 fluxes of gross primary productivity (GPP), ecosystem respiration (ER), and net ecosystem exchange (NEE) during 1990–2015 from 148 terrestrial high-latitude (i.e., tundra and boreal) sites to a…
Landelinus, l’auteur de la plaque-boucle mérovingienne au Christ de l’Apocalypse découverte à Ladoix-Serrigny (Côte-d’Or) serait-il saint Landeli…
2021
Cette note concerne l’exceptionnelle plaque-boucle au Christ cavalier de l’Apocalypse découverte à Ladoix-Serrigny et étudiée précédemment dans cette revue. Son objectif est de discuter l’hypothèse récemment émise selon laquelle saint Landelin, qui a vécu au VIIe siècle dans le nord de la Gaule, serait Landelinus, l’auteur de cet objet. Plusieurs arguments militent en faveur de cette interprétation qui nous paraît donc plausible, même si elle reste fragile. Il est également envisagé de localiser cette fabrication dans le prestigieux monastère de Luxeuil. Mais il s’agit là encore d’une hypothèse. This note concerns the exceptional buckle-plate to the Christ cavalier of the Apocalypse discove…
Influence of land cover in the atmospheric water vapor content and the generation of summer storms in the Turia River Basin
2022
Les tronades d'estiu representen una font d’aigua important en la conca mediterrània, ja que aporten aigua durant els mesos més secs de l’any, amb la qual cosa ajuden a mantenir els cabdals dels principals rius. Aquests sistemes convectius estan associats a les circulacions de brisa que dominen durant l'estiu. La brisa es canalitza a través de les valls assolint les capçaleres dels principals rius on es generen línies de convergència, és a dir, zones on les masses d’aire superficials s’injecten a capes més altes de l’atmosfera i donen lloc a aquest tipus de fenòmens meteorològics. A part de la topografia, altres factors que poden influenciar la formació de tronades d'estiu són els fluxos su…
Du peintre au musée : Jules Adler et Luxeuil
2016
International audience
Simulació de fluxos de carboni terrestres mitjançant teledetecció i modelització d'ecosistemes
2018
The main goal of this thesis is the establishment of a framework to analyze the Spanish forest ecosystems in terms of their role in the carbon cycle. In particular, the carbon fluxes that they exchange with atmosphere are modeled to evaluate their potential as carbon sinks and biomass reservoirs. Gross fluxes are estimated by a production efficiency model relying on the Monteith’s approach. The emphasis is put in characterizing the water stress effects on the light use efficiency and, eventually, on the GPP. Six alternatives are evaluated. Among them, the ones using the ratio between the MODIS actual and potential evapotranspiration, and the soil moisture from SMOS demonstrate that it is po…
The impact of in-canopy wind profile formulations on heat flux estimation using the remote sensing-based two-source model for an open orchard canopy …
2010
Abstract. For open orchard and vineyard canopies containing significant fractions of exposed soil (>50%), typical of Mediterranean agricultural regions, the energy balance of the vegetation elements is strongly influenced by heat exchange with the bare soil/substrate. For these agricultural systems a "two-source" approach, where radiation and turbulent exchange between the soil and canopy elements are explicitly modelled, appears to be the only suitable methodology for reliably assessing energy fluxes. In strongly clumped canopies, the effective wind speed profile inside and below the canopy layer can highly influence the partitioning of energy fluxes between the soil and vegetation comp…
L'occupation humaine du Grand-Duché de Luxembourg à l'âge du Bronze Final : inventaire des sites et bilan de l'état de la documentation
2017
International audience
Chemistry and fluxes of major and trace element from worldwide passive degassing volcanoes: a critical review
2015
Volcanic emissions represent one of the most important natural sources of trace elements (e.g. As, Cd, Cu, Hg, Pb, Sb, Tl and Zn) into the atmosphere, sequentially influencing the hydrosphere, lithosphere and biosphere. The human health hazard during episodic volcanic eruptions generally follows from deposition of coarse and fine particles (2.5-10 and < 2.5 μm) that produces effects such as asthma and lung and respiratory disease. Regarding passive degassing volcanoes, the harmful effects of fluorine fumigation are known both for vegetation (foliar necrosis) and human/animals (fluorosis), but only a few studies have been focused on the effects of potentially toxic trace elements. From a …
Rapid sensing of volcanic SO₂ fluxes using a dual ultraviolet camera system: new techniques and measurements at Southern Italian volcanoes
2012
Volatiles carry crucial information on pre- to sin-eruptive processes at active volcanoes. Measurements of gas emission rates (crater plumes, fumaroles, diffuse soil degassing) therefore improve our understanding of degassing processes and subsurface magmatic and hydrothermal conditions, and contribute to eruption forecasting. Recent technological developments in spectroscopy have allowed, over the last 30 years, the remote sensing of magmatic volatile emissions from quiescent and erupting degassing volcanoes. These data-sets have contributed to discovering cyclic gas flux components due to periodic magma supply and replenishment in magma storage zones, and/or timescales of magma migration …