Exploració per tema "Núvols"

Ara es mostren els items 1-16 de 16

    • A WRF simulation of an episode of contrails covering the entire sky 

      Mazón Bueso, Jordi; Pino González, David (2016-07-20)
      Article
      Accés obert
      On 21 September 2012 the entire sky was covered by contrails over the Gulf of Lyon (NW of the Mediterranean basin). These clouds were well recorded by ground observers as well as by Meteosat imagery. The atmospheric ...

    • Aircraft clouds: from chemtrail pseudoscience to the science of contrails 

      Mazón Bueso, Jordi; Costa, Marcel; Pino González, David (2018-04-03)
      Article
      Accés obert
      The most frequent statements and arguments found in pseudoscience websites and forums supporting the existence of so-called aircraft chemtrails can be refuted with a scientific explanation of the processes resulting in the ...

    • Buoyancy reversal in cloud-top mixing layers 

      Mellado González, Juan Pedro; Stevens, Bjorn; Schmidt, Heiko; Peters, Norbert (2009-04-28)
      Article
      Accés obert
      A theoretical and numerical small-scale study of the evaporative cooling phenomenon that might appear in the stratocumulus-topped boundary layers is presented. An ideal configuration of a cloud-top mixing layer is ...

    • Caracterización y estudio de plantas fotovoltaicas 

      Forniés Campos, Álvaro (Universitat Politècnica de Catalunya, 2022-10-26)
      Treball Final de Grau
      Accés obert
      L'objectiu d'aquest Treball Final de Grau és l'estudi i l'anàlisi de la influència dels components i de les condicions atmosfèriques en el funcionament d'una planta fotovoltaica. Aquest estudi es durà a terme fent ús del ...

    • Cloud motion estimation in seviri image sequences 

      Marcello, Javier; Eugenio, Francisco Javier; Marqués Acosta, Fernando (2009)
      Text en actes de congrés
      Accés obert
      Determination of atmospheric dynamic characteristics from remote sensing imagery is fundamental in weather and climate studies. The SEVIRI radiometer, on board the MSG, with its 12 bands and 15 minutes sensing ...

    • Clouds’ microphysical properties and their relationship with lightning activity in northeast Brazil 

      Pereira de Abreu, Lizandro; Andrade Goncalves, Weber; Vieira Mattos, Enrique; Rodrigues Mutti, Pedro; Torres Rodrigues, Daniele; Silva, Marcos Paulo Aráujo da (Multidisciplinary Digital Publishing Institute (MDPI), 2021-11-01)
      Article
      Accés obert
      The Northeast region of Brazil (NEB) has a high rate of deaths from lightning strikes (18% of the country’s total). The region has states, such as Piauí, with high mortality rates (1.8 deaths per million), much higher than ...

    • Contrails distribution and variation in Catalonia during the last three years (2014-2016) 

      Partal Camps, M. Núria (Universitat Politècnica de Catalunya, 2017-10-30)
      Treball Final de Grau
      Accés obert
      Since the industrial revolution human activities have modified the climate and the weather; for instance, creating the heat island effect due to urbanization, or increasing cloud cover. Particularly, exhausts for airplanes ...

    • Direct Numerical Simulation of evaporative cooling at the lateral boundary of shallow cumulus clouds 

      Abma, Dick; Heus, Thijs; Mellado González, Juan Pedro (2013-07-23)
      Article
      Accés obert
      This study investigates the dynamics of the subsiding shell at the lateral boundary of cumulus clouds, focusing on the role of evaporative cooling. Since the size of this shell is well below what large-eddy simulations can ...

    • Direct Numerical Simulations of a smoke cloud-top mixing layer as a model for stratocumuli 

      de Lozar, Alberto; Mellado González, Juan Pedro (2013-08-05)
      Article
      Accés obert
      A radiatively driven cloud-top mixing layer is investigated using direct numerical simulations. This configuration mimics the mixing process across the inversion that bounds the stratocumulus-topped boundary layer. The ...

    • Els mecanismes d'electrificació del núvol 

      Montañá Puig, Juan (Servei Meteorològic de Catalunya - Ed. Valant 2003 S.L., 2004)
      Capítol de llibre
      Accés restringit per decisió de l'autor
      Els mecanismes d'electrificació d'un núvol, basats en l'intercanvi de càrregues elèctriques entre partícules, avui en dia encara no són perfectament coneguts. Les teories formulades fins ara s’ocupen d’alguns dels processos ...

    • Geometrical and optical properties of cirrus clouds in Barcelona, Spain: analysis with the two-way transmittance method of 4 years of lidar measurements 

      Gil Díaz, Cristina; Sicard, Michaël; Comerón Tejero, Adolfo; Oliveira, Daniel Camilo Fortunato dos Santos; Muñoz Porcar, Constantino; Rodríguez Gómez, Alejandro Antonio; Lewis, Jasper R.; Welton, Ellsworth J.; Lolli, Simone (European Geosciences Union (EGU), 2024-02-20)
      Article
      Accés obert
      In this paper a statistical study of cirrus geometrical and optical properties based on 4 years of continuous ground-based lidar measurements with the Barcelona (Spain) Micro Pulse Lidar (MPL) is analysed. First, a review ...

    • Learning of models of temporal point clouds 

      Pascual González, Nicolás (Universitat Politècnica de Catalunya, 2020-01-31)
      Projecte Final de Màster Oficial
      Accés restringit per acord de confidencialitat

    • Probability density functions in the cloud-top mixing layer 

      Mellado González, Juan Pedro; Stevens, Bjorn; Schmidt, Heiko; Peters, Norbert (2010-08-19)
      Article
      Accés obert
      The cloud-top mixing layer is an idealized configuration often employed in the literature to study local aspects (over length scales of the order of 10 m) of the top of stratocumulus-topped mixed layers. Latent heat effects ...

    • Reduction of the entrainment velocity by sedimentation in stratocumulus 

      de Lozar, Alberto; Mellado González, Juan Pedro (2017-03-01)
      Article
      Accés obert
      The effect of sedimentation on stratocumulus entrainment is investigated using direct numerical simulations of a cloud-top mixing layer driven by radiative and evaporative cooling. The simulations focus on the meter and ...

    • Study of low-order numerical effects in the two-dimensional cloud-top mixing layer 

      Dietze, Eckhard; Mellado González, Juan Pedro; Stevens, Bjorn; Schmidt, Heiko (2013-06-01)
      Article
      Accés obert
      Large-eddy simulation (LES) has been extensively used as a tool to understand how various processes contribute to the dynamics of the stratocumulus layer. These studies are complicated by the fact that many processes are ...

    • Wind Shear and Buoyancy Reversal at the Top of Stratocumulus 

      Mellado González, Juan Pedro; Stevens, Bjorn; Schmidt, Heiko (2014-03-01)
      Article
      Accés obert
      A numerical experiment is designed to study the interaction at the stratocumulus top between a mean vertical shear and the buoyancy reversal due to evaporative cooling, without radiative cooling. Direct numerical simulation ...