Search results for " water content"

showing 10 items of 77 documents

High resolution remote estimation of soil surface water content by a thermal inertia approach

2009

Summary The spatial distribution of soil surface water content in a bare soil was evaluated by a thermal inertia approach from high resolution visible/near infrared (VIS/NIR) and thermal infrared (TIR) airborne data. Given that the relationship between the thermal inertia and the soil water content strongly depends on the accurate estimation of the soil thermal conductivity, two different empirical models were applied to estimate it. Remotely estimated water contents were tested with time domain reflectometry (TDR) measurements collected on a 110 × 90 m 2 bare field in coincidence with airborne over-flights. The thermal conductivity model by Johansen (1975) produced more accurate estimates …

Hydrology (agriculture)Thermal conductivitySoil thermal propertiesThermal inertia Soil water content Surface temperature Soil thermal conductivitySoil waterEnvironmental scienceMineralogySettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliConductivityReflectometryWater contentSurface waterWater Science and Technology
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Assessing the performance of thermal inertia and Hydrus models to estimate surface soil water content

2017

The knowledge of soil water content (SWC) dynamics in the upper soil layer is important for several hydrological processes. Due to the difficulty of assessing the spatial and temporal SWC dynamics in the field, some model-based approaches have been proposed during the last decade. The main objective of this work was to assess the performance of two approaches to estimate SWC in the upper soil layer under field conditions: the physically-based thermal inertia and the Hydrus model. Their validity was firstly assessed under controlled laboratory conditions. Thermal inertia was firstly validated in laboratory conditions using the transient line heat source (TLHS) method. Then, it was applied in…

Hydrus010504 meteorology & atmospheric sciencesMean squared error0208 environmental biotechnologyHydrus numerical modelSoil science02 engineering and technologyHydrus numerical model; Soil thermal inertia; Soil water content; Sparse vegetation; Applied MathematicsThermal diffusivitySoil water content01 natural scienceslcsh:TechnologySparse vegetationlcsh:ChemistrySoil thermal propertiesSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliGeneral Materials ScienceTime domainSoil thermal inertiaReflectometryInstrumentationlcsh:QH301-705.50105 earth and related environmental sciencesRemote sensingFluid Flow and Transfer Processeslcsh:TProcess Chemistry and TechnologyApplied MathematicsSettore ICAR/02 - Costruzioni Idrauliche E Marittime E IdrologiaGeneral EngineeringRanginglcsh:QC1-999020801 environmental engineeringComputer Science Applicationslcsh:Biology (General)lcsh:QD1-999lcsh:TA1-2040Soil waterEnvironmental sciencelcsh:Engineering (General). Civil engineering (General)lcsh:Physicssoil water content; soil thermal inertia; Hydrus numerical model; sparse vegetationSettore ICAR/06 - Topografia E Cartografia
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Optimizing subsurface dripline installation depth with Hydrus 2D/3D to improve irrigation water use efficiency in the central Tunisia

2015

The main objective of the work is to optimize drip installation depth for Eggplant crop irrigated with surface or subsurface drip irrigation systems to improve irrigation Water Use Effeciency (WUE), by means of field measurements and simulations carried out with Hydrus-2D model. Initially, a comparison between simulated Soil Water Contents (SWC) and the corresponding measured in two plots, in which laterals with coextruded emitters are laid on the soil surface (T0) and at 20 cm depth (T20), respectively. In order to choose the best position of the lateral, the results of different simulation run, carried out by choosing a deeper installation (T45) depth. Simulated SWC’s resulted fairly clos…

HydrusTechnologywater use efficiencyTEnvironmental engineeringSoil scienceSoil surfaceDrip irrigationSubsurface drip irrigation soil water contents Hydrus 2D water use efficiency RMSEsoil water contentsIrrigation waterRMSESubsurface drip irrigationHydrus 2DSoil waterWater uptakeDNS root zoneEnvironmental scienceSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliWater-use efficiencySafety Risk Reliability and Quality
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Partitioning of Aerosol Particles in Mixed-phase Clouds at a High Alpine Site

2007

6 German Aerospace Centre, D-82234, Wessling, Germany * Now at Institute for Atmospheric and Climate Science, ETH Zurich, 8092 Zurich, Switzerland Abstract The partitioning of aerosol particles between the cloud and the interstitial phase (i.e., unactivated aerosol) has been investigated during several Cloud and Aerosol Characterization Experiments (CLACE) conducted in winter and summer 2004 and winter 2005 at the high alpine research station Jungfraujoch (3,580 m altitude, Switzerland). Ambient air was sampled using different inlets in order to determine the scavenged fraction of aerosol particles, F Scav , and of black carbon, F Scav,BC . They denote the fraction of the aerosol volume con…

Ice crystalsParticle numberLiquid water contentPhase (matter)Ice nucleusEnvironmental scienceAtmospheric sciencescomplex mixturesMass fractionWater vaporAerosol
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A method for soil moisture probes calibration and validation of satellite estimates

2017

Graphical abstract

Land surface processes010504 meteorology & atmospheric sciencesOtras Ciencias de la Tierra y relacionadas con el Medio AmbienteClinical Biochemistry0211 other engineering and technologiesContext (language use)Soil science02 engineering and technologySoil water content01 natural sciencesREMOTE SENSINGCiencias de la Tierra y relacionadas con el Medio Ambiente//purl.org/becyt/ford/1 [https]//purl.org/becyt/ford/1.5 [https]Pedotransfer functionCalibrationlcsh:ScienceWater contentComputingMethodologies_COMPUTERGRAPHICS021101 geological & geomatics engineering0105 earth and related environmental sciencesRemote sensingSOIL MOISTURE AND OCEAN SALINITY (SMOS)Oceanografía Hidrología Recursos HídricosSoil classificationMethod ArticleSOIL WATER CONTENTRemote sensingSoil typeMedical Laboratory TechnologySoil Moisture and Ocean Salinity (SMOS)LAND SURFACE PROCESSESSoil waterEnvironmental scienceSatellitelcsh:QCIENCIAS NATURALES Y EXACTASMethodsX
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Volatiles in pantellerite magmas: A case study of the Green Tuff Plinian eruption (Island of Pantelleria, Italy)

2013

Abstract The Green Tuff (GT) Plinian eruption, the largest in magnitude at Pantelleria, erupted 3 to 7 km3 DRE of pantellerite magma and a small volume of trachyte. Fifty-nine anorthoclase-hosted melt inclusions from the two basal pumice members were analyzed by FT-IR spectroscopy in order to assess the pre-eruptive H2O content in the pantellerite melt. Microanalytical methods were used to determine major element, Cl, F and S contents. Melt inclusions and glassy groundmasses have a nearly homogeneous pantelleritic composition (peralkaline index = 1.9-2.2) and variable water contents ranging from 1.4 to as high as 4.2 wt %, i.e. much higher than the 1.4 wt % of earlier published studies. The…

LavaSettore GEO/07 - Petrologia E PetrografiaGeochemistryTrachyteMagma chamberStrombolian eruptionGeophysicsEffusive eruptionGeochemistry and PetrologyPumiceMagmaThe Green Tuff (GT) Plinian eruption the largest in magnitude at Pantelleria erupted 3 to 7 km 3 DRE of pantellerite magma and a small volume of trachyte. Fifty-nine anorthoclase-hosted melt inclusions from the two basal pumice members were analyzed by FT-IR spectroscopy in order to assess the pre-eruptive H2Ocontent in the pantellerite melt. Microanalytical methods were used to determine major element Cl F and S contents. Melt inclusions and glassy groundmasses have a nearly homogeneous pantelleritic composition (peralkaline index = 1.9-2.2) and variable water contents ranging from 1.4 to as high as 4.2 wt % i.e. much higher than the 1.4 wt % of earlier published studies. The chlorine content is constant at about 1 wt %. Combined Cl and H2O data were used to estimate a confining pressure of about 50 MPa (depth around 2-3 km) for the GT magma chamber. The chamber was characterized by a compositional zoning with a dominant pantellerite overlying a trachyte magma. Soon after the GT eruption intra-caldera volcanism was dominated by the eruption of voluminous trachyte lavaflows while pantellerite melt production resumed after about 20 ka with numerous low-volume mildly explosive (Strombolian) to effusive eruptions. Comparison with data from the literature reveals that despite the differentexplosivity the post-caldera Strombolian eruptions and the GT Plinian eruption were fed by pantelleritic magmas with similar water contents. Chlorine and CO2contents suggest that the young magma reservoirs feeding the Strombolian to effusive activity were deeper (h≥4.5 km) than the much larger (based on erupted volumes) magma chamber which fed the GT eruptionGeologyMelt inclusionsJournal of Volcanology and Geothermal Research
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Equivalences between refractive index and equilibrium water content of conventional and silicone hydrogel soft contact lenses from automated and manu…

2007

PURPOSE: The purpose of the present study was to develop mathematical relationships that allow obtaining equilibrium water content and refractive index of conventional and silicone hydrogel soft contact lenses from refractive index measures obtained with automated refractometry or equilibrium water content measures derived from manual refractometry, respectively. METHODS: Twelve HEMA-based hydrogels of different hydration and four siloxane-based polymers were assayed. A manual refractometer and a digital refractometer were used. Polynomial models obtained from the sucrose curves of equilibrium water content against refractive index and vice-versa were used either considering the whole range…

Materials scienceSiliconesRefractive indexBiomedical EngineeringAnalytical chemistryBiocompatible Materials02 engineering and technologyBiomaterials03 medical and health sciences0302 clinical medicineRefractometerHumansBrix sucrose scaleBrix scaleCLR 12-70Water contentSoft contact lenseschemistry.chemical_classificationScience & TechnologyEquilibrium water contentWaterHydrogelsAtago N2EsucrosePolymerSilicone hydrogelconventional soft contact lensesContact Lenses Hydrophilic021001 nanoscience & nanotechnologyContact lensRefractometrychemistrySelf-healing hydrogelsSilicone hydrogel030221 ophthalmology & optometry0210 nano-technologyRefractometryRefractive indexJournal of Biomedical Materials Research Part B: Applied Biomaterials
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Soil water content assessment: Seasonal effects on the triangle method

2016

Among indirect estimations of the soil water content in the upper layer, the "triangle method" is based on the relationship between the optical and thermal features sensed via Earth Observation. These features are controlled by water content at surface and within root zone, but also by meteorological forcing including air temperature and humidity, and solar radiation. Night and day-time MODIS composite land-surface temperature (LST) allowed applying the thermal admittance version of the method; by taking into account the temporal admittance of the soil, this version was previously found achieving high accuracy in estimate the soil water content at high spatial resolution within a short time…

MeteorologyHumidityTriangle MethodForcing (mathematics)Thermal AdmittanceAtmospheric sciencesAridNormalized Difference Vegetation IndexGeographyAltitudeSoil Water ContentSoil waterDNS root zoneWater contentSeasonal Effects
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Impact of cloud processes on aerosol particle properties: results from two ATR-42 flights in an extended stratocumulus cloud layer during the EUCAARI…

2011

Abstract. Within the European Aerosol Cloud Climate and Air Quality Interactions (EUCAARI) project, the Meteo France research aircraft ATR-42 was operated from Rotterdam airport during May 2008, to perform scientific flights dedicated to the investigation of aerosol-cloud interactions. Therein, the objective of this study is to illustrate the impact of cloud processing on the aerosol particles physical and chemical properties. The presented results are retrieved from measurements during a double-flight mission from Rotterdam (Netherlands) to Newcastle (UK) and back using data measured with compact Time of Flight Aerosol Mass Spectrometer (cToF-AMS) and Scanning Mobility Particle Sizer (SMPS…

Meteorologybusiness.industryCloud computingAtmospheric sciencesMarine stratocumulusAerosolchemistry.chemical_compoundchemistryLiquid water contentScanning mobility particle sizerEnvironmental scienceParticleSulfatebusinessSea salt aerosol
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A Radiation Fog Model with a Detailed Treatment of the Interaction between Radiative Transfer and Fog Microphysics

1990

Abstract A one-dimensional radiation fog model is presented which includes a detailed description of the interaction between atmospheric radiative transfer and the microphysical structure of the fog. Aerosol particles and activated cloud droplets are treated using a two-dimensional joint size distribution whereby the activation process of aerosols is explicitly modeled. For this purpose a new positive definite semi-Lagrangian advection scheme is developed that produces only small numerical diffusion and is numerically very efficient. For the radiative calculations, time dependent attenuation parameters are determined from the actual particle size distributions. The diffusional growth of the…

PhysicsAtmospheric ScienceAtmospheric radiative transfer codesClassical mechanicsMicrophysicsSettlingAdvectionLiquid water contentRadiative transferMechanicsNumerical diffusionAerosolJournal of the Atmospheric Sciences
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