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Njouenwet Ibrahim Vondou Derbetini Appolinaire Fita Dassou Elisabeth Ayugi Brian Odhiambo Nouayou Robert 《Natural Hazards》2021,106(1):561-577
Natural Hazards - Drought is a recurrent phenomenon in the Sudano–Sahelian region of Cameroon. However, it has received very little attention, especially, on its impacts on the growing season... 相似文献
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Temperature response to future urbanization and climate change 总被引：2，自引：0，他引：2
Daniel Argüeso Jason P. Evans Lluís Fita Kathryn J. Bormann 《Climate Dynamics》2014,42(7-8):2183-2199
This study examines the impact of future urban expansion on local near-surface temperature for Sydney (Australia) using a future climate scenario (A2). The Weather Research and Forecasting model was used to simulate the present (1990–2009) and future (2040–2059) climates of the region at 2-km spatial resolution. The standard land use of the model was replaced with a more accurate dataset that covers the Sydney area. The future simulation incorporates the projected changes in the urban area of Sydney to account for the expected urban expansion. A comparison between areas with projected land use changes and their surroundings was conducted to evaluate how urbanization and global warming will act together and to ascertain their combined effect on the local climate. The analysis of the temperature changes revealed that future urbanization will strongly affect minimum temperature, whereas little impact was detected for maximum temperature. The minimum temperature changes will be noticeable throughout the year. However, during winter and spring these differences will be particularly large and the increases could be double the increase due to global warming alone at 2050. Results indicated that the changes were mostly due to increased heat capacity of urban structures and reduced evaporation in the city environment. 相似文献
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Javier Cotin Manuel García-Tarrasón Carolina Sanpera Lluis Jover Xavier Ruiz 《Estuarine, Coastal and Shelf Science》2011
The Ebro catchment, the largest river basin in Spain, includes various heavily industrialized areas. Among these is the Flix site, where a chemical plant has been operating since the beginning of the 20th century. This extended operational period, together with the construction of a dam next to the factory around 1960, resulted in the accumulation of large amounts of heavily polluted sediments in the adjacent riverbed, many of which are contaminated by mercury. Pollutants from Flix are carried downstream by the Ebro River to its delta. In order to assess the transfer of mercury to the complex river estuary ecosystem, we studied the ecology of the tern community living there as these birds segregate into a range of habitats. For this purpose, first we used stable isotope analysis (SIA) (δ34S, δ13C, δ15N) of eggs to determine the trophic ecology and habitat partitioning of several tern species (Common, Sandwich, Little, Gull-Billed and Whiskered Tern) breeding sympatrically, in order to link their foraging ecology with habitat types. Next we measured mercury concentrations in eggs to monitor the input of this metal into the diverse habitats. With the exception of the Little Tern, the other terns used a restricted habitat range in the Ebro Delta, as shown by C and S isotopes; the Gull-Billed and Whiskered Tern foraged in freshwater habitats, while the Common and Sandwich Tern used marine habitats. This restricted feeding behavior of the Gull-Billed and Common Tern contrasts with previous reports in other breeding sites. The Little Tern, which showed a wide range of isotopic values, was found to be an opportunistic forager but fed mainly in saltpans, a feeding habitat not reported previously for this species in this area. We found that mercury concentrations are related to foraging habitat and diet, and are unexpectedly higher in species feeding on demersal prey in marine habitats and also higher in birds feeding in saltpans than in those feeding in freshwater habitats. The mercury concentrations found in the Little and Common Tern eggs sampled in “Punta de la Banya” may be sufficiently high to endanger breeding success. 相似文献
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Aguilar-Meléndez Armando Pujades Lluis G. Barbat Alex H. Monterrubio-Velasco Marisol de la Puente Josep Lantada Nieves 《Natural Hazards》2022,110(3):1649-1691
Natural Hazards - There are personal and institutional decisions that can increase the seismic resilience of the buildings in a city. However, some of these decisions are possible if we have basic... 相似文献
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Marc Polliand Urs Schaltegger Martin Frank Lluis Fontboté 《International Journal of Earth Sciences》2005,94(2):231-242
During late Early to Late Cretaceous, the Peruvian coastal margin underwent fast and oblique subduction and was characterized by important arc plutonism (the Peruvian Coastal Batholith) and formation of volcanosedimentary basins known as the Western Peruvian Trough (WPT). We present high-precision U–Pb ages and initial Hf isotopic compositions of zircon from conformable volcanic and crosscutting intrusive rocks within submarine volcanosedimentary strata of the WPT hosting the Perubar massive sulfide deposit. Zircons extracted from both the volcanic and intrusive rocks yield concordant U–Pb ages ranging from 67.89±0.18 Ma to 69.71±0.18 Ma, indicating that basin subsidence, submarine volcanism and plutonic activity occurred in close spatial and temporal relationship within the Andean magmatic arc during the Late Cretaceous. Field observations, satellite image interpretation, and plate reconstructions, suggest that dextral wrenching movements along crustal lineaments were related to oblique subduction. Wrench tectonics is therefore considered to be the trigger for the formation of the WPT as a series of pull-apart basins and for the emplacement of the Coastal Batholith. The zircon initial Hf values of the dated magmatic rocks fall between 5.5 and 7.4, and indicate only very subordinate influence of a sedimentary or continental component. The absence of inherited cores in the zircons suggest a complete lack of old basement below the WPT, in agreement with previous U–Pb and Sr isotopic data for batholithic rocks emplaced in the WPT area. This is supported by the presence of a most likely continuous block of dense (~3.0 g/cm3) material observed beneath the WPT area on gravimetric crustal cross sections. We suggest that this gravimetric anomaly may correspond to a piece of lithospheric mantle and/or oceanic crust inherited from a possible Late Permian–Triassic rifting. Such young and mafic crust was the most probable source for arc magmatism in the WPT area. 相似文献
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High-resolution sea wind hindcasts over the Mediterranean area 总被引：1，自引：1，他引：0
M. Menendez M. García-Díez L. Fita J. Fernández F. J. Méndez J. M. Gutiérrez 《Climate Dynamics》2014,42(7-8):1857-1872
The goal of this study is to develop a high-resolution atmospheric hindcast over the Mediterranean area using the WRF-ARW model, focusing on offshore surface wind fields. In order to choose the most adequate model configuration, the study provides details on the calibration of the experimental saet-up through a sensitivity test considering the October–December 2001 period (the 2001 super-storm event in the West Mediterranean). A daily forecast outperforms the spectral technique of previous products and the boundary data from ERA-Interim reanalysis produces the most accurate estimates in terms of wind variability and hour-to-hour correspondence. According to the sensitivity test, two data sets of wind hindcast are produced: the SeaWind I (30-km horizontal resolution for a period of 60 years) and the SeaWind II (15-km horizontal resolution for 20 years). The validation of the resulting surface winds is undertaken considering two offshore observational datasets. On the one hand, hourly surface buoy stations are used to validate wind time series at specific locations; on the other hand, wind altimeter satellite observations are considered for spatial validation in the whole Mediterranean Sea. The results obtained from this validation process show a very good agreement with observations for the southern Europe region. Finally, SeaWind I and II are used to characterize offshore wind fields in the Mediterranean Sea. The statistical structure of sea surface wind is analyzed and the agreement with Weibull probability distribution is discussed. In addition, wind persistence and extreme wind speed (50 year return period) are characterized and relevant areas of wind power generation are described by estimating wind energy quantities. 相似文献
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Coronato Tanea Carril Andrea F. Zaninelli Pablo G. Giles Julián Ruscica Romina Falco Magdalena Sörensson Anna A. Fita Lluis Li Laurent Z. X. Menéndez Claudio G. 《Climate Dynamics》2020,55(9-10):2543-2556
Based on a series of experiments conducted by two regional climate models (RCA4 and LMDZ) with and without soil moisture-atmosphere coupling, we investigate the role of soil moisture on the occurrence of surface air temperature extremes and its persistence in Southeastern South America. Our analysis reveals that both factors, soil moisture-atmosphere coupling and relatively drier soil conditions, enhance the temperature extremes. In addition, the existence of soil-atmosphere coupling and the associated soil moisture variability is crucial for the development of the extremes in SESA. The key role of soil-atmosphere coupling is also reflected in the intrinsic persistence of hot days, which is greater in simulations with interactive soil moisture than in those with prescribed soil conditions. In the absence of soil-atmosphere coupling, the imprint of the anomalous dry (and also wet) soil conditions on the intensity and persistence of hot days is weaker.
相似文献10.
Vega Prez Gracia Jos Antonio Canas Lluis G. Pujades Jaume Claps Oriol Caselles Francesc García Raul Osorio 《Journal of Applied Geophysics》2000,43(2-4)
This paper describes the ground-penetrating radar (GPR) survey performed inside the Cathedral of Valencia, Spain. It is part of historical studies performed in the Cathedral in order to add information to old maps and documents in the Cathedral Archives and also to analyze the extent and importance of potentially destructive moisture areas that were appearing on the floor. The construction of the Cathedral of Valencia occurred in three stages, all of which are well-documented in the Cathedral Archives with detailed drawings, maps, and charts. The radar data were successful in locating crypts, ossuaries, sepulchers, and graves, and the location of ancient walls that existed before the final Cathedral expansion. Three cultural layers corresponding to the three periods of construction were also identified corresponding to the Roman, Arabian and Middle Age Epochs. Measurements of relative sub-floor moisture were obtained by comparing dielectric permittivity changes and radar velocity differences between materials in humid and non-humid areas. 相似文献