Search results for "Lluvia"
showing 10 items of 49 documents
Precipitaciones mediterráneas y movimientos de masa en margas de los valles de Alcoi
1992
SE REALIZA UNA EVALUACION ESPACIO-TEMPORAL DE LAS PRECIPITACIONES (ANUALES, TANDAS MAXIMAS DE VARIOS DIAS DE DURACION Y MAXIMAS EN 24 H) QUE PRECEDEN Y ACOMPAÑAN A MOVIMIENTOS DE LADERA EN UN AMBIENTE TIPICAMENTE MEDITERRANEO. A PARTIR DE CASOS OBSERVADOS (LA ROCA 1991B) SE DISTINGUEN DOS TIPOS DE PRECIPITACION (VOLUMEN, INTENSIDAD, DURACION) , QUE, A GRANDES RASGOS, VAN ASOCIADOS A DIFERENTES MORFOGENESIS POR MOVIMIENTOS DE LADERA ETC... (A)
Eolian and fluvial sedimentation in the southwestern Sinai Mountains, Egypt: a record of flash floods during the late Pleistocene
2012
Wadis emerging from the southwestern Sinai Mountains (Egypt) westwards to the Gulf of Suez are filled by >40 m thick late Pleistocene sediments, which have been subsequently incised to bedrock after the Last Glacial Maximum (LGM). Sedimentation and erosion resulted from changes in the basin's hydrological conditions caused by climate variations. Sediment characteristics indicate distinct processes ranging from high to low energy flow regimes. Airborne material is important as a sediment source. The fills are associated with alluvial fans at wadi mouths at the mountain fronts. Each alluvial fan is associated and physically correlated with the respective sediment fill in its contributi…
Urban growth (1956-2012) and soil sealing in the metropolitan area of Valencia (Eastern Spain)
2019
[EN] The aim of this study is to understand the urban growth dynamics from the mid-1950s to 2012 in the Metropolitan Area of Valencia, eastern Spain, and its impact on soils. The study area is a very interesting example of the many changes in land use and land cover in the landscape of Mediterranean alluvial plains. The analysis of urban growth was based on photo interpretation of aerial photographs and GIS based methodology. At a detailed scale (1:10,000), results show that there has been a highly dynamic process produced by the extent of land developed as urban area. In 1956 only 3,441 hectares (9.3% of the overall study area) were occupied by urban use. In 2012 the total sealed surface w…
The MIS 5 palaeoenvironmental record in the SE Mediterranean coast of the Iberian Peninsula (Río Antas, Almería, Spain)
2015
Se realiza un estudio detallado del episodio cálido MIS 5 en la zona sureste de la Península Ibérica. Se realiza la reconstrucción paleoambiental a partir del estudio polínico y biomarcadores de un sondeo perforado en la costa de Almería. La cronología se estableció a partir del método de racemizaciónd e aminoácidos.Landwards of a MIS5 bar, a borehole core (SRA) was analyzed to establish the relationship between the lagoonal record and the raised beach deposits in the surroundings of the Antas river mouth and to reconstruct the Pleistocene palaeoenvironmental evolution 5 of the southern Mediterranean coast of the Iberian Peninsula. 63 samples were recovered for amino acid racemization datin…
Relationship of Weather Types on the Seasonal and Spatial Variability of Rainfall, Runoff, and Sediment Yield in the Western Mediterranean Basin
2020
Producción Científica
Las crecidas en ramblas valencianas mediterráneas
2001
This paper takes into account the characterisation of ephemeral stream hydrology from Mediterranean environments. The heavy floods that these countries suffer are due to firstly, the physical watershed features (steep slopes, scarced vegetation cover and thin soils) and, secondly, to the intense and variable rainfall. Large quantities of precipitation fall in a matter of hours, or even minutes, over very steep catchments, causing catastrophic flash-floods, with very pointed hydrographs and short time lags. Using hydrological daily data from the Rambla de la Viuda basin and five-minute data from both Barranc de Carraixet and Rambla de Poyo basins, we have analysed the rainfall- runoff proces…
Geochemical characterization and health risk assessment in two diversified environmental settings (Southern Italy).
2021
An integrated approach using chemical and microbial indicators has been tested in two different sites of the Campania Plain (Southern Italy) with different land use covering and different hydrogeological features in order: (1) to define the water-rock interaction processes, (2) to differentiate sources of pollution in a detailed way (3) to evaluate the degree of water quality in the studied alluvial aquifer and (4) to identify the most worrying elements for human's health. Groundwater have showed a HCO3-Ca signature for both investigated sites, and a progressive enrichment in alkali ions has been highlighted moving from the boundary of the plain toward the coastal areas, due to groundwater …
Umbrales de lluvia, daños y niveles de alerta en la Comunidad Valenciana
2016
Ponencia presentada en: X Congreso de la Asociación Española de Climatología celebrado en Alicante entre el 5 y el 8 de octubre de 2016. [ES]En el contexto de los riesgos climáticos, muchas de las alarmas tempranas de precipitaciones extremas se basan en umbrales de lluvia que, a su vez, están relacionados con niveles probables de daños. A pesar de los grandes esfuerzos que se han venido realizando en los últimos años para discriminar bien los umbrales de estas alertas, uno de los principales problemas es la emisión de un número excesivo de avisos, hecho que puede crear alarmismo. El presente trabajo constituye un estudio aplicado que aborda la detección de indicadores de lluvia y la estima…
Evolución de episodios pluviométricos en la Demarcación Hidrográfica del Júcar (1989-2016): del recurso al riesgo
2020
Este trabajo aborda la clasificación y evolución diacrónica de los episodios de lluvia (1989-2016) en ambientes mediterráneos, en la Demarcación Hidrográfica del Júcar. En base a datos del SAIH, y siguiendo criterios hidrológicos, se seleccionan 698 episodios, que se caracterizan con indicadores de precipitación acumulada, intensidad y persistencia. Mediante un análisis cluster se identifican tres tipologías (episodios de recurso limitado, de gran recurso a largo plazo y de riesgo) y se analiza su evolución temporal, estableciendo diferencias entre los episodios de interior y de litoral. Los resultados muestran una tendencia hacia el incremento del riesgo en detrimento del recurso en los tr…
Scour on alluvial bed downstream of grade-control structures
2004
This paper describes an approach for predicting local scour downstream of grade control structures. The developed analysis applies the incomplete self-similarity (ISS) theory for deducing some physically based dimensionless groups controlling the geometrical pattern of the scour profile. The scour measurements available in the literature in conjunction with numerous unpublished data allow a multiregressive calibration of the ISS relationships. The experimental sample includes different bed grain-size distributions and scales of the erosive phenomenon. The results prove that the ratio between the upstream water head and the weir height is able to explain the measurements of scour depth carri…