Sample records for FLUJO DE CALOR (heat flux)
from WorldWideScience.org

Sample records 1 - 20 shown. Select sample records:



1

Diseño de un prototipo para la medición de flujo de calor mediante calorimetría directa usando sensado por variación de temperatura/ Design of a prototype for measuring heat flux using direct calorimetry by temperature variation measurements

Reyes, Oscar; Cadena, Oscar; Correa, Rodrigo
2007-12-01

Resumen en español Este artículo muestra las principales características del módulo para el monitoreo de flujo de calor mediante sensado de temperatura en pacientes que se encuentran en estado post-operatorio, como planteamiento de solución a los inconvenientes y falencias que presentan los actuales métodos de seguimiento del consumo de calorías. Este proyecto es un prototipo que se construye con el fin de guiar estudios posteriores sobre el tema, por lo tanto, las pruebas de calibración de flujo de calor y temperatura no se realizarán en seres humanos sino en generadores de calor controlados. Resumen en inglés This article presents the main characteristics of the design and construction of a prototype to measure heat flux, acquiring temperature variation and using noninvasive temperature sensors. The conditions of a post-surgical patient are related to energy consumption as a part of the metabolic answer due to stress that represents the patient decaying condition. One of the actions adopted to improve and accelerate the patient process of recovery, is the appropriate handling (mas) of the metabolism, since its adequate control can contribute to the necessary nutrients for the evolution and recovering of the person under care. This project is a prototype, and therefore, tests should not be used on human beings but only on controlled heat generators.

Scientific Electronic Library Online (Spanish)

2

Estimación de la Evapotranspiración de Tomate Usando el Modelo Interacción Suelo - Vegetación - Atmósfera (ISBA)/ Estimation of Tomato Evapotranspiration Using the Interaction Between Soil, Biosphere and Atmosphere (ISBA) Model

Olioso, Albert; Ortega-Farías, Samuel; Valdés, Héctor; Antonioletti, Rodrigo
2005-09-01

Resumen en español Se realizó un estudio para evaluar la evapotranspiración real (ET) estimada por el modelo interacción suelo-vegetación-atmósfera (ISBA) sobre un cultivo de tomates (Lycopersicon esculentum Mill.), el cual estaba ubicado en la Estación Experimental Panguilemo de la Universidad de Talca (35°23’ lat. Sur; 71°40’ long. Oeste, 110 m.s.n.m.). Con este objetivo se usó un sistema de Bowen instalado en la parte central del cultivo tomates para medir el flujo de calor la (mas) tente (LE), flujo de radiación neta (Rn), flujo de calor sensible (H) y flujo de calor del suelo (G) durante la temporada 1998-1999. Simultáneamente, una estación meteorológica automática instalada sobre pasto en condiciones de referencia fue utilizada para medir temperatura del aire, humedad relativa, velocidad del viento, radiación solar y precipitaciones. La ET actual estimada por el modelo ISBA fue evaluada usando el flujo de calor latente obtenido del sistema de Bowen. Los resultados de este estudio indicaron que el modelo ISBA fue capaz de estimar LE horario con una desviación media (bias) de 6 W m-2 y un error cuadrático medio (RMSE) equivalente a 65 W m-2. En términos diarios, el modelo ISBA estimó la ET con una bias y un RMSE de 0,11 mm d-1 y 0,50 mm d-1, respectivamente. El análisis de sensibilidad indicó que con errores (o variaciones) de ± 30% en los valores de las principales variables de entrada (índice de área foliar, altura del cultivo, albedo y resistencia estomática mínima), el modelo ISBA fue capaz de estimar adecuadamente la ET con errores menores al 6% Resumen en inglés A study was carried out to evaluate the real evapotranspiration (ET) estimated by the “Interaction among Soil-Biosphere-Atmosphere” (ISBA) model on a tomato (Lycopersicon esculentum Mill.) crop, which was located at the Panguilemo Experimental Station of the Universidad de Talca (35º23’ S lat, 71°40’ W long, 110 m.o.s.l.). For that purpose, a Bowen system installed in the central part of the tomato crop was used to measure latent heat flux (LE), net radiation flux ( (mas) Rn), soil heat flux (G) and sensitive heat flux (H) during 1998-1999 season. Simultaneously, an automatic meteorological station installed over grass under reference conditions was used to measure air temperature, relative humidity, wind speed, solar radiation, and precipitation. The actual evapotranspiration estimated by the ISBA model was evaluated using latent heat fluxes measured by the Bowen system. Results indicated that the model was able to estimate LE on an hourly basis with a root mean square error (RMSE) of 65 W m-2 and a bias less than 6 W m-2. On a daily basis, the model estimated ET with RMSE and bias of 0.50 mm d-1 and 0.11 mm d-1, respectively. The sensitivity analysis indicated that with errors (or variations) of ± 30% in the values of the main input variables (leaf area index, crop height, albedo and minimum stomatal resistance), the ISBA model was able to estimate the ET with errors less than 6%

Scientific Electronic Library Online (Spanish)

3

Efecto de tratamiento isotérmico sobre los cambios de fases de una aleacion AA8011

González, Verónica; López, Ramón; Luiggi, Ney
2006-05-01

Resumen en español En el presente trabajo se detectaron las transformaciones de fases isotérmicas que ocurren en una aleación AA8011 homogeneizada durante 24 horas a 600°C. Un calentamiento continuo no isotérmico a 10°C/min entre 20 y 600°C nos permitió establecer a través de medidas de calorimetría diferencial de barrido (DSC) las temperaturas a las cuales se genera una transformación estructural, identificando las temperaturas características en 271.8, 450 y 474.2°C. Isotermas (mas) in situ a estas temperaturas revelaron cambios en el flujo de calor asociados a la existencia de procesos de precipitación y redisolución de fases. Resumen en inglés In this work we have detected the isothermal phase transformations occurring in an AA8011 alloy which was homogenized by 24 hours at 600°C. A non isothermal heating at 10°C/min between 20 and 600°C permitted us to determine, by means of differential scanning calorimetry (DSC), the characteristic temperatures of the structural transformations, which are identified at 271.8, 450 and 474.2°C. Isothermal kinetics in situ at these temperatures reveal that heat flux changes which are associated with process of precipitation and dilution of structural phases.

Scientific Electronic Library Online (Spanish)

4

Respuestas inmunológicas y de enzimas antioxidantes en la ostra perla Pinctada imbricata (Mollusca: Pteridae) expuesta a niveles subletales de fuel oil nº6

Nusetti, Osmar; Marcano, Leida; Zapata, Edgar; Esclapés, Mercedes; Nusetti, Sonia; Lodeiros, César
2004-06-01

Resumen en portugués Avaliou-se as respostas imunológicas e de sistemas enzimáticos antioxidantes que participam no controle de toxicidade de oxido radicais na ostra pérola Pinctada imbricata, depois da exposição aguda (7d) a 25 e 100% da fracção solúvel de Fuel Oil Nº6 (FSA), uma fonte de hidrocarburos poli-aromáticos e de metais pesados em ecossistemas marinhos. A atividade de lisozimas na glândula digestiva e a fagocitosis nos hemocitos foram determinadas como respostas imunoló (mas) gicas humoral e celular, respectivamente, usando leveduras mortas por calor como antígeno para o ensaio da fagocitosis. A viabilidade e número total de hemocitos também foram determinados. As enzimas antioxidantes glutationa transferasa (GST), glutationa reductasa (GR), glutationa peroxidasa (GPx) e catalasa (CAT) foram avaliadas em extratos de glândula digestiva e manto. Na glândula digestiva, a ex-WSF treatments resulted in significant increases of GST and CAT. In the mantle, both experimental treatments increased GPx and decreased GST activity, while CAT was not affected. Immunological indicators were not affected by the treatments, excepting cellular viability which decreased under exposure to 100% WSF. The results suggest that the antioxidant enzymes in the digestive gland and mantle of posição a FSA incrementou significativamente as atividades de GST e CAT. No manto se produziu um aumento na atividade de GPx e um descenso nas atividades de GST e GR, enquanto que CAT não foi afetada. A exceção da viabilidade celular à exposição de 100% FSA, os indicadores imunológicos não foram afetados pelo contaminante. Os resultados mostram a sensibilidade das enzimas antioxidantes da glândula digestiva e manto à exposição subletal aguda de Fuel Oil Nº6, sugerindo um aumento no fluxo de oxiradicais e possíveis manifestações bioquímicas prejudiciais associadas com estresse oxidativo em ambos tecidos. Estes parâmetros podem ser utilizados como ferramentas potenciais para o estudo de toxicidade de contaminantes no meio marinho. Resumen en español Se evaluó las respuestas inmunológicas y de sistemas enzimáticos antioxidantes que participan en el control de toxicidad de oxidoradicales en la ostra perla Pinctada imbricata, después de la exposición aguda (7d) a 25 y 100% de la fracción soluble de Fuel Oil Nº6 (FSA), una fuente de hidrocarburos poliaromáticos y de metales pesados en ecosistemas marinos. La actividad de lisozimas en la glándula digestiva y la fagocitosis en los hemocitos fueron determinadas com (mas) o respuestas inmunológicas humoral y celular, respectivamente, usando levaduras muertas por calor como antígeno para el ensayo de la fagocitosis. La viabilidad y número total de hemocitos también fueron determinados. Las enzimas antioxidantes glutationa transferasa (GST), glutationa reductasa (GR), glutationa peroxidasa (GPx) y catalasa (CAT) fueron evaluadas en extractos de glándula digestiva y manto. En la glándula digestiva, la exposición a FSA incrementó significativamente las actividades de GST y CAT. En el manto se produjo un aumento en la actividad de GPx y un descenso en las actividades de GST y GR, mientras que CAT no fue afectada. A excepción de la viabilidad celular a la exposición de 100% FSA, los indicadores inmunológicos no fueron afectados por el contaminante. Los resultados muestran la sensibilidad de las enzimas antioxidantes de la glándula digestiva y manto a la exposición subletal aguda de Fuel Oil Nº6, sugiriendo un incremento en el flujo de oxiradicales y posibles manifestaciones bioquímicas perjudiciales asociadas con estrés oxidativo en ambos tejidos. Estos parámetros pueden ser utilizados como herramientas potenciales para el estudio de toxicidad de contaminantes en el medio marino. Resumen en inglés The immune and antioxidant enzyme defenses in pearl oyster Pinctada imbricata were evaluated after shotterm (7d) exposure to 25 and 100% watersoluble fraction (WSF) of Fuel Oil Nº6, a source of polyaromatic hydrocarbon and heavy metal contamination of marine ecosystems. Lysozyme activity in the digestive gland and the phagocytic activity of hemocytes were measured as humoral and cellular immunological responses, respectively, using heat killed yeast cells as antigen for (mas) the phagocytosis assay. The viability and total number of hemocytes were recorded. The detoxifying enzymes Glutathione-S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR) and catalase (CAT) were evaluated from the digestive gland and mantle extracts. In the digestive gland the exposure to P. imbricata are sensitive to short-term exposure to Fuel Oil Nº6, suggesting an increased oxiradical flux and biochemical manifestations of oxidative injury in both tissues. These parameters should be considered as potential tools for the biomonitoring of marine environmental contamination.

Scientific Electronic Library Online (Spanish)

5

Nota sobre la naturaleza del calor en la termodinámica relativista

Sandoval-Villalbazo, A; García-Colín, L.S
2007-08-01

Resumen en español Un argumento muy simple muestra que la inclusión del flujo de calor en el tensor ímpetu-energía relativista tiene limitaciones que provienen de la existencia de un término proporcional a la aceleración hidrodinámica. Más aún, su justificación a partir de la teoría cinética relativista limita su validez sólo al fluido ideal. Resumen en inglés It is shown by means of a simple argument that the introduction of the heat flux in the relativistic energy-momentum tensor yields certain limitations that can be traced back to the existence of a term proportional to the hydrodynamic acceleration. Moreover, this acceleration term can only be properly justified in the case of a simple ideal fluid.

Scientific Electronic Library Online (Spanish)

6

Aplicación del Análisis Dimensional Discriminado a la Convección Libre en una Placa Vertical a través de un Medio Poroso/ Application of Discriminated Dimensional Analysis to Free Convection in a Vertical Flat Plate Through a Porous Medium

Madrid, Carmelo N; Navarro, José R; Herranz, Antonio
2006-01-01

Resumen en español En este trabajo, se presenta un estudio sobre la convección libre laminar en una placa vertical impermeable a través de un medio poroso empleando análisis dimensional discriminado. Se han obtenido soluciones para el espesor de la capa límite y el coeficiente de transmisión del calor en los casos de placa isoterma y con flujo uniforme de calor, soluciones que coinciden con las analíticas salvo una constante de proporcionalidad. La discriminación de las dimensiones d (mas) el espacio permite expresar, en un solo monomio, la solución del problema. También la aplicación del análisis dimensional discriminado permite asociar a los números de Rayleigh y de Nusselt un significado físico relacionado con la geometría del problema Resumen en inglés Laminar free convection in an impermeable flat plate trough a porous medium has been studied in this paper using discriminated dimensional analysis. With this method, which avoids complicate analytical calculus, solutions were obtained for the thickness of the boundary layer and the heat transfer coefficient in cases involving an isothermal plate and uniform heat flux These solutions agree with analytical results, except for a numerical proportional constant. Discriminati (mas) on of the dimensions leads to an single monomial for the solution of the problem. Also, application of discriminated dimensional analysis relates the classical numbers Ra y and Nu y with the geometry of the problem giving them a physical meaning

Scientific Electronic Library Online (Spanish)

7

Water and nutrient fluxes off Northwest Africa

Pastor, Maria V.; Pelegrí, Josep Lluís; Hernández Guerra, Alonso; Font, Jordi; Salat, Jordi; Emelianov, Mikhail
2008-01-31

Digital.CSIC (Spain)

8

Using sap flow measurements to quantify water consumption in apricot trees

Nicolás Nicolás, Emilio; Torrecillas Melendreras, Arturo; Alarcón Cabañero, Juan José
2006-09-30

Digital.CSIC (Spain)

10

Submillimeter Evidence for the Coeval Growth of Massive Black Holes and Galaxy Bulges

Page, M. J.; Stevens, J. A.; Mittaz, J. P. D.; Carrera, Francisco J.
2002-02-05

Digital.CSIC (Spain)

11

Sintering behaviour of steatite materials with barium carbonate flux

Vela, E.; Peiteado, M.; García, F.; Caballero, A. C.; Fernández Lozano, José Francisco
2007-01-01

Digital.CSIC (Spain)

12
13

Relación entre los componentes del balance de energía y la resistencia estomática en el cultivo de melón bajo acolchado plástico: (con 2 figuras y 1 cuadro)

Munguia, J; Zermeño, A; Quezada, R; De La Rosa, M; Ibarra, L; Torres-B, A
2004-12-01

Resumen en inglés This study analyzes the relationship between the changes in the energy balance components and the muskmelon stomatal resistance under plastic mulch conditions. This experiment was conducted in a muskmelon crop with and without plastic mulch, from April to July, 1998. To measure the energy balance components (net radiation (Rn), latent heat flux LE, sensible heat flux H and surface soil flux G). Eddy covariancestations were used; one was located in the plastic mulch sectio (mas) n and the otherin the section withno plastic mulch.Each stationconsisted offast response kryptonhygrometer, aonedimensionalsonic anemometer anda fine wirethermocouple. The stations also have a net radiometer, 2 soil heat flux plates and two soil thermocouples of 4 parallel ends. The station in the plastic mulch section also had measurements of wind speed and direction. The stations gave average 20-min values of Rn, LE, H and G. The stomatal resistance was measured by using two diffusion porometers. The measurements were taken once every 8 days in 2 leaves/plants of 4 plants per section (with and without plastic mulch). Theses measurements were taken from 13:00 to 14:00 hrs. The results of this study indicated that the stomatal resistance, the apparent temperature of the surface, and the canopy temperatures were higher under plastic mulch. The energy components, net radiation, latent heat flux and sensible heat flux were also higher under plastic mulch. The plastic mulch induced a precocity to the crop, with an early harvest.

Scientific Electronic Library Online (Spanish)

14

Physical and biogeochemical fluxes and net budgets in the subpolar and temperate North Atlantic

Álvarez, Marta; Bryden, H. L.; Pérez, Fiz F.; Ríos, Aida F.; Rosón, Gabriel
2002-03-01

Digital.CSIC (Spain)

15

Nomsothermal multiphase flow of brine and gas through saline media

Carrera Ramírez, Jesús; Gens, Antonio; Olivella Pastallé, Sebastià
2009-01-01

Digital.CSIC (Spain)

16

Monitoring land degradation risk using ASTER data: The non-evaporative fraction as an indicator of ecosystem function

García García, Mónica; Oyonarte, Cecilio; Villagarcía, Luis; Contreras, Sergio; Domingo, Francisco; Puigdefábregas, Juan
2008-07-25

Digital.CSIC (Spain)

17

Mass fluxes in the Canary Basin

Machín, Félix; Hernández Guerra, Alonso; Pelegrí, Josep Lluís
2006-08-01

Digital.CSIC (Spain)

18

Martian hydrogeology sustained by thermally insulating gas and salt hydrates

Kargel, Jeffrey S.; Furfaro, Roberto; Prieto Ballesteros, Olga; Rodríguez, J. Alexis P.; Montgomery, David R.; Gillespie, Alan R.; Marion, Giles M.; Wood, Stephen E.
2007-11-01

Digital.CSIC (Spain)

19

Influencia de la forma de los granos del fundente fundido CIS-F10 en la morfología y propiedades del metal depositado/ The influence of grains shape of the fused flux CIS-F10 on the morphology and properties of the deposited metal

Valdez, Marilene Álvarez; Pérez, Daniel Pérez; Gómez Pérez, Carlos R.; Oria, Víctor Miguel; Quintana Puchol, Rafael; Perdomo González, Lorenzo; Crespo, Amado Cruz
2010-06-01

Resumen en español En el trabajo se realiza un estudio de la forma de los granos del fundente fundido CIS-F10, tanto granulado con aire, como en agua, la geometría de la soldadura y sus propiedades. Para ello se realiza un análisis morfológico de los granos del fundente CIS-F10, sus densidades, la fluidez que presentan durante su apilamiento, su comportamiento higroscópico y las diferencias entre la cantidad de aire intergranular, durante su deposición sobre las piezas a soldar. La apl (mas) icación de estos procedimientos de estudio de materiales evidencia que el fundente granulado con aire (con un 79,2 % de partículas esféricas) posee una diferencia en su fluidez relativamente superior (34 %), una disminución del ángulo de talud (28,8 %) y un menor volumen relativo de aire intergranular (28,2 %), que el fundente granulado en agua, además de una disminución de la pendiente de crecimiento de la curva de humectación. La conjugación de estos aspectos producen una mayor penetración del arco de soldadura (8 %) y un menor ancho medio de la zona de afectada térmicamente (17 %), aunque no se evidencian diferencias en las propiedades metalográficas, ni mecánicas ( Resumen en inglés In the present paper, the shape of fused grains flux CIS-F10, granulated in air and in water, its effect on weld bead geometry and its properties were studied. Grains morphology, properties, fluidity during piling, hygroscopic behavior and the amount of air between the grains during use were analyzed. The application of these procedures showed evidence that flux granulated in air (79.2 % of spherical particles) has fluidity relatively higher (34 %), smaller shape angle (2 (mas) 8.8 %) and a lesser intergranular air per volume (28.2 %) than the flux granulated flux in water, despite the decrease in the slope of the humectation curve. The conjugation of these aspects improve penetration (8 %) and a reduction in the width of the heat affected zone (17 %) although neither metallographic nor mechanics (

Scientific Electronic Library Online (Spanish)

20

Igneous Origin of CO2 in Ancient and Recent Hot-Spring Waters and Travertines from the Northern Argentinean Andes

Gibert, Roger O.; Taberner, Conxita; Sáez, Alberto; Giralt, Santiago; Alonso, Ricardo N.; Edwards, R. Lawrence; Pueyo Mur, Juan José
2009-01-01

Digital.CSIC (Spain)

21

INTRODUCTION OF NEW J-OFURO LATENT HEAT FLUX DATA

Kubota, Masahisa; Tomita, Hiroyuki
2004-01-01

Resumen en inglés Japanese Ocean Flux data sets with Use of Remote sensing Observations (J-OFURO) includes various kinds of satellite data sets related to ocean surface flux and is provided for research people on the web site (http://dtsv.scc.u-tokai.ac.jp) and anonymous ftp site. Recently we extended the data period for several kinds of data included in J-OFURO. We introduce the new J-OFURO latent heat flux data and some results using new J-OFURO turbulent heat flux data in this paper

Scientific Electronic Library Online (Spanish)

22

Geostrophic Circulation and Heat Flux Across the Flemish Cap, 1988–2000

Gil, Julio; Sánchez, Ricardo; Cerviño López, Santiago; Garabana, Dolores
2004-09-24

Digital.CSIC (Spain)

23
26

Evaluación de dos métodos de determinación de la evapotranspiración de referencia en condiciones semiáridas

Villar i Mir, Josep Maria; Martínez-Cob, Antonio; Fuertes Lázaro, Santiago Javier
1998-07-01

Digital.CSIC (Spain)

27

Estimating the monthly pCO2 distribution in the North Atlantic using a self-organizing neural network

Telszewski, Maciej; Chazottes, A.; Schuster, Ute; Watson, Andrew J.; Moulin, C.; Bakker, Dorothee C.E.; González Dávila, Melchor; Johannessen, Truls; Körtzinger, Arne; Lüger, H.; Olsen, Are; Omar, A.; Padín, X. Antonio; Ríos, Aida F.; Steinhoff, Tobias; Santana-Casiano, J. Magdalena; Wallace, Douglas W.R.; Wanninkhof, Rik
2009-08-01

Digital.CSIC (Spain)

30

Estimating sensible and latent heat fluxes over rice using surface renewal

Castellví, F.; Martínez-Cob, Antonio; Pérez-Coveta, Olga

DRIVER (Spanish)

31

Estimating sensible and latent heat fluxes over rice using surface renewal

Castellví, F.; Martínez-Cob, Antonio; Pérez-Coveta, Olga
2006-09-01

Digital.CSIC (Spain)

32

Estimated Future Production of Desalinated Seawater in the MENA Countries and Consequences for the Recipients

Bashitialshaaer, Raed; Persson, Kenneth M; Larson, Magnus

Seawater desalination constitutes an important source for water supply to the population bordering the Arabian Gulf, the Mediterranean Sea, and the Red Sea. Desalination has advantages and disadvantages which may depend on the region, location, technology, impact and amount of fresh water production...

DRIVER (Spanish)

34

Efecto de los cambios microclimáticos sobre la fisiología del maíz durante el riego por aspersión

Martínez-Cob, Antonio; Cavero Campo, José; Aibar, Joaquín; Puig Basa, Miriam
2007-11-01

Digital.CSIC (Spain)

35

Determinación de los coeficientes de capa límite mediante el Modelo de Desgaste Nodal (MDN) para el estudio de la corrosión del crisol de alto horno

Barbés Fernández, M. F.; Barbés Fernández, M. A.; Marinas García, E.; Fernández Pérez, B.; Martín Duarte, R.; Mochón Muñoz, J.; Verdeja González, L. Felipe
2009-06-01

Digital.CSIC (Spain)

36

Daily patterns of mixing and nutrient concentrations during early autumn circulation in a small sheltered lake

Álvarez Cobelas, Miguel; Velasco, José Luis; Valladolid, María; Baltanás, Ángel; Rojo, Carmen
2005-04-01

Digital.CSIC (Spain)

37

Comparison of Three Operative Models for Estimating the Surface Water Deficit Using ASTER Reflective and Thermal Data

García García, Mónica; Villagarcía, Luis; Contreras, Sergio; Domingo, Francisco; Puigdefábregas, Juan
2007-06-06

Digital.CSIC (Spain)

38

Characterization of surface heat fluxes in the Mediterranean Sea from a 44-year high-resolution atmospheric data set

Ruiz, Simón; Gomis, Damià; Sotillo, Marcos G.; Josey, Simon A.

17 pages, 9 figures, 2 tables, 1 appendix.-- Available online Dec 27, 2007.-- Issue title: "Mediterranean climate: trends, variability and change". | We examine 44 years (1958–2001) of model data with the aim of characterizing the low frequency (the seasonal cycle and lower) variability of surface h...

DRIVER (Spanish)

40

Cambio microclimático y pérdidas por evaporación y arrastre en riego por aspersión en maíz

Martínez-Cob, Antonio; Aibar, Joaquín; Medina Pueyo, Eva Teresa
2006-05-01

Digital.CSIC (Spain)

41

Análisis de una ola de calor extrema en la región subtropical de américa del sur/ Analysis of an extreme heat wave over the subtropical region of South America

Norte, Federico Augusto; Seluchi, Marcelo Enrique; Gomes, Jorge Luis; Simonelli, Silvia Carmen
2007-12-01

Resumen en portugués Este trabalho analisa as condições meteorológicas que levaram à ocorrência de uma intensa onda de calor na região subtropical da América do Sul, com temperaturas máximas superiores aos 40°C imediatamente à leste dos Andes, na última semana de Janeiro de 2003. Para isso, os termos da Equação Termodinâmica foram avaliados a partir de simulações numéricas realizadas com o modelo regional Eta/CPTEC. O forte aumento da temperatura foi provocado pelo aquecim (mas) ento por compressão adiabática, produto da subsidência, e pelo aquecimento superficial imediatamente a leste dos Andes. A análise da Equação Omega Quase-Geostrófica permitiu estabelecer que a subsidência de grande escala se deveu fundamentalmente ao avanço de uma crista de onda longa nos níveis meios da atmosfera. Além disso, as observações e as simulações numéricas apontam para a ocorrência de subsidência forçada (vento Zonda) a leste dos Andes, associada ao deslocamento de um cavado de onda curta imerso na crista de onda longa, à aproximação de uma frente fria e ao deslocamento para o sul da Baixa Termo-orográfica. Esse fato, muito pouco freqüente no verão, em combinação com os processos descritos anteriormente, explicaria a ocorrência de recordes históricos de temperatura no oeste da Argentina. Resumen en inglés This work analyzes the meteorological conditions that caused the occurrence of an intense heat wave over subtropical South America, with temperatures higher than 40°C immediately to the east of the Andes, during the last week of January 2003. To that purpose the terms of the thermodynamic equation were evaluated through numerical simulations performed with the Eta/CPTEC regional model. The strong temperature increase was caused by adiabatic warming (subsidence) as wel (mas) l as by the net positive surface heat flux, especially to the east of the Andes. The qualitative analysis of the Quasi-Geostrophic Omega Equation revealed that the large-scale subsidence was the result of the cold horizontal temperature advection and the advance of a wide ridge at midlevels. Additionally, the presence of forced orographic subsidence (Zonda wind) is evident from observations and numerical simulations in connection with the passage of a short trough immerse in the wider ridge, the approach of a cold front and the southward progress of the thermal-orographic low. Since this phenomenon is quite uncommon during summer, its incidence in combination to the other processes previously described would explain the occurrence of extreme maximum temperatures over western Argentina.

Scientific Electronic Library Online (Spanish)

42

Analysis of a potential "solar radiation dose—dimethylsulfide—cloud condensation nuclei" link from globally mapped seasonal correlations

Vallina, Sergio M.; Simó, Rafel; Gassó, S.; Boyer-Montégut, C. de; Río, Evilio J. del; Jurado Capo, Elena

15 pages, 8 figures. | The CLAW postulate states that an increase insolar irradiance or in the heat flux to the ocean can trigger a biogeochemical response to counteract the associated increase in temperature and available sunlight. This natural (negative) feedback mechanism would be based on a mult...

DRIVER (Spanish)

43

Analysis of a potential "solar radiation dose—dimethylsulfide—cloud condensation nuclei" link from globally mapped seasonal correlations

Vallina, Sergio M.; Simó, Rafel; Gassó, S.; Boyer-Montégut, C. de; Río, Joaquín del; Jurado, Elena; Dachs, Jordi
2007-04-19

Digital.CSIC (Spain)

46

A mesoscale index to describe the regional circulation around the Balearic Islands

Monserrat, Sebastià; López-Jurado, José Luis; Marcos, Marta
2008-06-01

Digital.CSIC (Spain)

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A Comparison of New and Existing Equations for Estimating Sensible Heat Flux Density using Surface Renewal and Similarity Concepts

Castellví, F.; Snyder, R.L.; Baldocchi, D.D.; Martínez-Cob, Antonio

The definitive version is available at: http://www.agu.org/pubs/crossref/2006/2005WR004642.shtml | This paper describes two approaches for estimating sensible heat flux, using surface renewal and similarity concepts. One approach depends on a temperature structure function parameter and is valid in ...

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