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91.
Alejandro Ismael Monterroso-Rivas Ana Cecilia Conde-Álvarez José Luís Pérez-Damian Jorge López-Blanco Marcos Gaytan-Dimas Jesús David Gómez-Díaz 《Climatic change》2018,147(3-4):457-473
Vulnerability to climate change was evaluated for three different time periods: 1990, 2000, and 2010. Our objective was to discuss the scope of a multi-temporal assessment of vulnerability. The method used 55 indicators—with emphasis on the agricultural sector in Mexico—of which 27 were updated for the year 2010 and 33 were retrospectively estimated for the year 1990. The results show that in the 20-year study period, the exposure of the municipalities (and inhabitants) has increased, and sensitivity and adaptive capacity have decreased. The number of municipalities vulnerable to climate change declined over the 20-year period. We found that calculating vulnerability by adding exposure and sensitivity and subtracting adaptive capacity (E?+?S???AC) can lead to unintentional underestimation of total vulnerability. When rating vulnerability, care must be taken in what is reported: the results differ for the number of inhabitants versus the number of municipalities. Our previous published vulnerability evaluation was for the year 2000, so we wanted to evaluate the sensitivity of some variables and the vulnerability formula itself we used in that moment. It is possible to evaluate the vulnerability multi-temporally, which allows to evaluate the sensibility and calibration of the variables and indicators used and the reconsideration of their application. 相似文献
92.
Matyasovszky István Makra László Tusnády Gábor Csépe Zoltán Nyúl László G. Chapman Daniel S. Sümeghy Zoltán Szűcs Gábor Páldy Anna Magyar Donát Mányoki Gergely Erostyák János Bodnár Károly Bergmann Karl-Christian Deák Áron József Thibaudon Michel Albertini Roberto Bonini Maira Šikoparija Branko Radišić Predrag Gehrig Regula Rybníček Ondřej Severova Elena Rodinkova Victoria Prikhodko Alexander Maleeva Anna Stjepanović Barbara Ianovici Nicoleta Berger Uwe Seliger Andreja Kofol Weryszko-Chmielewska Elżbieta Šaulienė Ingrida Shalaboda Valentina Yankova Raina Peternel Renata Ščevková Jana Bullock James M. 《Theoretical and Applied Climatology》2018,133(1-2):277-295
Theoretical and Applied Climatology - The drivers of spatial variation in ragweed pollen concentrations, contributing to severe allergic rhinitis and asthma, are poorly quantified. We analysed the... 相似文献
93.
Gonzalo Gurrea Vicente Blanca-Giménez Vicente Pérez María-Antonia Serrano Juan-Carlos Moreno Solar Radiation Group of the Universitat Politècnica de València 《Asia-Pacific Journal of Atmospheric Sciences》2018,54(4):599-610
The goal of this study was to statistically analyse the variability of global irradiance and ultraviolet erythemal (UVER) irradiance and their interrelationships with global and UVER irradiance, global clearness indices and ozone. A prediction of short-term UVER solar irradiance values was also obtained. Extreme values of UVER irradiance were included in the data set, as well as a time series of ultraviolet irradiance variability (UIV). The study period was from 2005 to 2014 and approximately 250,000 readings were taken at 5-min intervals. The effect of the clearness indices on global irradiance variability (GIV) and UIV was also recorded and bi-dimensional distributions were used to gather information on the two measured variables. With regard to daily GIV and UIV, it is also shown that for global clearness index (kt) values lower than 0.6 both global and UVER irradiance had greater variability and that UIV on cloud-free days (kt higher than 0.65) exceeds GIV. To study the dependence between UIV and GIV the χ2 statistical method was used. It can be concluded that there is a 95% probability of a clear dependency between the variabilities. A connection between high kt (corresponding to cloudless days) and low variabilities was found in the analysis of bi-dimensional distributions. Extreme values of UVER irradiance were also analyzed and it was possible to calculate the probable future values of UVER irradiance by extrapolating the values of the adjustment curve obtained from the Gumbel distribution. 相似文献
94.
P. Ramírez Oyanguren C. Gonzlez Nicieza M.I. lvarez Fernndez C. Gonzlez Palacio 《Engineering Geology》2008,100(3-4):120-130
This paper analyzes the stability of the Llerin rockfill dam using Barton–Kjaernsli's shear criterion. To fit the parameters of this criterion, a direct shear test was designed that allows in situ calculation, using large-size samples of the shear stress at which failure is produced for different normal loads. These experimental values are then used to obtain more reliable values for the friction angle and the equivalent roughness of the rockfill material.The rockfill of Llerin dam is formed by a suitably ground gonfolite limestone rockfill that serves as a contention dam for a lagoon of mine tailings. The experimental results obtained in in situ tests were compared with those predicted by the shear criterion, subsequently determining the safety coefficient of the rockfill dam using the SLOPE computer program. We conclude that the values estimated via in situ testing permit the behaviour of the containment dam to be predicted more accurately. 相似文献
95.
Javier Roca-Pardiñas Tomás R. Cotos-Yáñez Rubén Pérez-Álvarez 《International journal of geographical information science》2017,31(4):676-693
We propose a method to evaluate the existence of spatial variability in the covariance structure in a geographically weighted principal components analysis (GWPCA). The method, that is extensive to locally weighted principal components analysis, is based on performing a statistical hypothesis test using the eigenvectors of the PCA scores covariance matrix. The application of the method to simulated data shows that it has a greater statistical power than the current statistical test that uses the eigenvalues of the raw data covariance matrix. Finally, the method was applied to a real problem whose objective is to find spatial distribution patterns in a set of soil pollutants. The results show the utility of GWPCA versus PCA. 相似文献
96.
Galileo Constellation Design 总被引:2,自引:0,他引:2
Álvaro Mozo-García Esperanza Herráiz-Monseco Ana Belén Martín-Peiró Miguel M. Romay-Merino 《GPS Solutions》2001,4(4):9-15
A significant effort has been carried out in Europe to define the European Global Navigation Satellite System (GNSS), named
Galileo Satellites flying in Medium Earth Orbits (MEO) will compose the system (according to the most recent architecture
definition baseline); a regional complement of geosynchronous satellites may be required to increase performances over Europe
and maybe also to provide some specific communication services. Nominal medium performances are envisaged, but they will be
increased by means of augmentation systems (local or wide area), or even by using simultaneously other GNSSs such as GPS.
All the involved requirements make the design process quite complex. A powerful software tool, Elcano, has been developed
for this purpose; its capabilities will be outlined, and the results of the design process will be presented. ? 2001 John
Wiley & Sons, Inc. 相似文献
97.
K-Ar ages of illite-muscovite and fission track ages of zircon and apatite were determined from various lithotypes of the Bükkium, which forms the innermost segment of the Western Carpathians. The stratigraphic ages of these Dinaric type formations cover a wide range from the Late Ordovician up to the Late Jurassic. The grade of the orogenic dynamo-thermal metamorphism varies from the late diagenetic zone through the anchizone up to the epizone (chlorite, maximally biotite isograd of the greenschist facies). The K-Ar system of the illite-muscovite in the < 2 m grain-size fraction approached equilibrium only in epizonal and high-temperature anchizonal conditions. The orogenic metamorphism culminated between the eo-Hellenic (160-120 Ma) phase connected to the beginning of the subduction in the Dinarides, and the Austrian (100-95 Ma) phase characterized by compressional crustal thickening. No isotope geochronological evidence was found for proving any Hercynian recrystallization. The stability field of fission tracks in zircon was approached using the thermal histories of the different tectonic units. A temperature less than 250°C and effective heating time of 20–30 Ma had only negligible effects on the tracks, whereas total annealing was reached between 250 and 300°C. Apatite fission track ages from the Paleozoic and Mesozoic formations show that the uplift of the Bükk Mountains occurred only in the Tertiary (not earlier than ca. 40 Ma ago). Thermal modeling based on apatite fission track length spectra and preserved Paleogene sediment thickness data proved that the Late Neogene burial of the recently exhumed plateau of the Bükk Mountains exceeded 1 km. 相似文献
98.
Álvaro-Francisco Morote-Seguido María Hernández-Hernández 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2016,116(2):190-201
The intense urbanization of the Mediterranean coast as a result of the development of residential-tourist activities since the 1960s, especially from the mid-1990s to 2008, has generated new urban environments associated with extensive urban typologies. These include gardens linked to houses with outdoor spaces that are shared between all of the residents of the residential developments. The aim of this study is to determine the main characteristics of these new urban green spaces and their effect on domestic water consumption in Alicante (Spain). To do this, we analysed the characteristics that define these types of gardens (surface area, density, plant species and irrigation system) and determined their water needs using the Water Use Classifications of Landscape Species method. The main conclusions are that the increase in paved areas is one of the strategies to reduce water consumption in spaces where turf grass is the most common plant species. This is due to increased water prices and lack of water resources. 相似文献
99.
Recognition criteria,characteristics and implications of the fluvial to marine transition zone in ancient deltaic deposits (Lajas Formation,Argentina) 总被引:1,自引:0,他引:1 下载免费PDF全文
Marcello Gugliotta Stephen S. Flint David M. Hodgson Gonzalo D. Veiga 《Sedimentology》2016,63(7):1971-2001
The seaward end of modern rivers is characterized by the interactions of marine and fluvial processes, a tract known as the fluvial to marine transition zone, which varies between systems due to the relative strength of these processes. To understand how fluvial and tidal process interactions and the fluvial to marine transition zone are preserved in the rock record, large‐scale outcrops of deltaic deposits of the Middle Jurassic Lajas Formation (Neuquén Basin, Argentina) have been investigated. Fluvial–tidal indicators consist of cyclically distributed carbonaceous drapes in unidirectional, seaward‐oriented cross‐stratifications, which are interpreted as the result of tidal modulation of the fluvial current in the inner part of the fluvial to marine transition zone. Heterolithic deposits with decimetre‐scale interbedding of coarser‐grained and finer‐grained facies with mixed fluvial and tidal affinities are interpreted to indicate fluvial discharge fluctuations (seasonality) and subordinate tidal influence. Many other potential tidal indicators are argued to be the result of fluvial–tidal interactions with overall fluvial dominance or of purely fluvial processes. No purely tidal or tide‐dominated facies were recognized in the studied deposits. Moreover, fluvial–tidal features are found mainly in deposits interpreted as interflood (forming during low river stage) in distal (delta front) or off‐axis (interdistributary) parts of the system. Along major channel axes, the interpreted fluvial to marine transition zone is mainly represented by the fluvial‐dominated section, whereas little or no tide‐dominated section is identified. The system is interpreted to have been hyposynchronous with a poorly developed turbidity maximum. These conditions and the architectural elements described, including major and minor distributary channels, terminal distributary channels, mouth bars and crevasse mouth bars, are consistent with an interpretation of a fluvial‐dominated, tide‐influenced delta system and with an estimated short backwater length and inferred microtidal conditions. The improved identification of process interactions, and their preservation in ancient fluvial to marine transition zones, is fundamental to refining interpretations of ancient deltaic successions. 相似文献
100.
R. H. Adams R. A. Cerecedo-López L. A. Alejandro-Álvarez V. I. Domínguez-Rodríguez J. L. Nieber 《International Journal of Environmental Science and Technology》2016,13(9):2249-2260
A pipeline right-of-way contaminated with light crude in 1979 and subsequently burned shows severe hydrophobicity, poor infiltration rates, and loss of vegetative cover. To evaluate alkaline desorption as a treatment method, surface soil samples were collected and analyzed pre- and post-treatment. Samples had total petroleum hydrocarbon concentrations of 2800–63,100 mg/kg, severe water repellency, critical moisture 2–5 times above the in situ moisture content, but no acute toxicity. Thus, water repellency, rather than toxicity, is causing the loss of vegetation. Samples were treated with 0.1 N NaOH in two doses (1:3; soil/solution), with complete drainage between doses. Finally, each soil sample was washed with an equal volume or water and allowed to drain completely. For more hydrophobic samples, repeated treatments, without rinsing between each treatment, were made. Post-treatment, the samples were re-analyzed for water repellency and critical moisture content. In samples with initial water repellency values in the range of 5.0–6.7 M, the repellency was reduced 94–100 % and below critical levels to avoid soil hydrophobicity in field conditions. The other samples with initial water repellency values in the range of 10–13 M could not be recovered with single treatment, but sequential treatments reduced the hydrocarbon content up to 87 % and reduced the hydrophobicity to levels low enough or nearly low enough to avoid severe water repellency in the field. Currently, field studies are being carried out to evaluate this treatment method at the site, as a stand-alone method and in combination with organic amendment. 相似文献