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111.
Anne Browning-Aiken Barbara Morehouse Allison Davis Margaret Wilder Robert Varady David Goodrich Rebecca Carter Denise Moreno Emily Dellinger McGovern 《Climatic change》2007,85(3-4):323-341
This paper reviews regional climate knowledge and vulnerability in the northern Mexico San Pedro River Basin, with a focus
on water quality, quantity, and management issues on the Mexican side of the border. A discussion based on the available literature
is supplemented by a survey assessing concerns about water and the quality and usability of climate and hydrologic information
available to water managers and communities. The surveys indicate that the central concern for urban residents is the lack
of reliable potable water due to frequent service breakdowns–with climate change and variability, specifically drought and
high temperatures, as contributing factors. Water managers desire appropriate meteorological and hydrologic information to
improve planning strategies, but access to this information remains limited. Considerable disagreement exists about who should
pay for previously free or low-cost water and wastewater treatment. Urban users have little incentive to conserve because
of the present flat, low rate and frustration with service. In rural areas, while a majority of ranchers recognize that variable
climate and water loss could increasingly jeopardize their lifestyle, they seldom use meteorological information in planning
or modify their water consumption. Climate vulnerability also includes potential for serious environmental health issues due
to the presence of heavy metals and organic contaminants in the San Pedro. 相似文献
112.
Moreno Wilmer Emilio García Soares Gabriela Borges Pires Júlio César Gall Sotelo Daniela Govoni Moura Cássio Stein 《Geotechnical and Geological Engineering》2021,39(6):4593-4613
Geotechnical and Geological Engineering - A large part of the Guarani Aquifer is located in the state of Rio Grande do Sul (Brazil) and additionally possesses a recharge area located in its central... 相似文献
113.
This paper examines changes in gender relations in a small coastal community as a result of the 2010 Chile earthquake and tsunami. Vulnerability and resilience are used as a conceptual framework to analyse these changes. Based on empirical evidence from a seven-year longitudinal study and quasi-ethnographic work, we explore changes in power relations at the different stages of the disaster and longer-term recovery as well as the conditions that fostered these changes. Our findings show distinct patterns of change. First, disasters can trigger long-lasting changes that challenge historical patriarchal relations. Second, while vulnerability increases following a disaster, resilience can potentially counteract women’s vulnerability. We propose that resilience can be a pathway to produce long-term changes in gender relations and empower women in the context of disasters. 相似文献
114.
Elías Moreno George Casella Antonio Garcia-Ferrer 《Stochastic Environmental Research and Risk Assessment (SERRA)》2005,19(3):191-204
The Bayesian literature on the change point problem deals with the inference of a change in the distribution of a set of time-ordered data based on a sample of fixed size. This is the so-called retrospective or off-line analysis of the change point problem. A related but different problem is that of the sequential change point detection, mainly analyzed from a frequentist viewpoint. While the former typically focuses on the estimation of the position in which the change point occurs, the latter is a testing problem which has a natural formulation as a Bayesian model selection problem. In this paper we provide such a Bayesian formulation, which generalizes previous formulations such as the well-known CUSUM stopping rule. We show that the conventional improper priors (also called non-informative, objective or default), cannot be used either for sequential detection of the change or for retrospective estimation. Then, we propose objective intrinsic prior distributions for the unknown model parameters. The normal and Poisson cases are studied in detail and examples with simulated and real data are provided. 相似文献
115.
Stratigraphical, sedimentological and paleoecological studies undertaken in lagoonal sediments of the Ria Formosa barrier lagoon indicate that a number of present-day aligned beaches outcropping within the marsh and detached from mainland (marsh detached beaches, MDB) represent the remnants of former ephemeral flood deltas, which established following barrier breaching induced by extreme storms from circa 1270 BC onwards. Dating of these beaches suggests that they resulted from multiple events of flooding separated both in time and space. Repeated emplacement of tidal deltas following overwash of the same location of the barrier is represented in the stratigraphical record by buried and partly overlapping marsh beaches. It is suggested that further refinement of the data presented in this paper and the extension of the stratigraphic survey to the entire lagoonal space will substantiate the usefulness of the stratigraphic record as a proxy to hindcast a time series of extreme storminess extending far beyond the instrumental and historical records. 相似文献
116.
Forecast combination has been studied in econometrics for a long time, and the literature has shown the superior performance of forecast combination over individual predictions. However, there is still controversy on which is the best procedure to specify the forecast weights. This paper explores the possibility of using a procedure based on Entropy Econometrics, which allows setting the weights for the individual forecasts as a mixture of different alternatives. In particular, we examine the ability of the Data-Weighted Prior Estimator proposed by Golan (J Econom 101(1):165–193, 2001) to combine forecasting models in a context of small sample sizes, a relative common scenario when dealing with time series for regional economies. We test the validity of the proposed approach using a simulation exercise and a real-world example that aims at predicting gross regional product growth rates for a regional economy. The forecasting performance of the Data-Weighted Prior Estimator proposed is compared with other combining methods. The simulation results indicate that in scenarios of heavily ill-conditioned datasets the approach suggested dominates other forecast combination strategies. The empirical results are consistent with the conclusions found in the numerical experiment. 相似文献
117.
L. López-Escobar M. A. Parada R. Hickey-Vargas F. A. Frey P. D. Kempton H. Moreno 《Contributions to Mineralogy and Petrology》1995,119(4):345-361
Calbuco volcano is a Late Pleistocene-Holocene composite stratovolcano located at 41°20 S, in the southern region of the Southern Volcanic Zone of the Andes (SSVZ; 37°–46° S). In contrast to basalt and basaltic andesite, which are the dominant lava types on the volcanic front from 37° to 42° S, Calbuco lavas are porphyritic andesites which contain a wide variety of crustal xenoliths. They have SiO2 contents in the 55–60% range, and have comparatively low K2O, Rb, Ba, Th and LREF abundances relative to other SSVZ centers. Incompatible element abundance ratios are similar to those of most SSVZ volcanics, but 87Sr/86Sr and 143Nd/144Nd are respectively higher and lower than those of adjacent volcanic centers. Basalts from nearby Osorno stratovolcano, 25 km to the northeast, are similar to other basaltic SSVZ volcanoes. However, basalts from several minor eruptive centers (MEC), located east of Calbuco and Osorno volcano along the Liquiñe-Ofqui fault zone (LOFZ), are enriched in Ba, Nb, Th and LREE, and have higher La/Yb and lower Ba/La, K/La and Rb/La. 87Sr/86Sr and 143Nd/144Nd in MEC basalts are respectively lower and higher than those of Osorno and Calbuco lavas. We suggest that MEC basalts were produced by lower extents of mantle melting than basalts from Osorno and other SSVZ stratovolcanoes, probably as a result of lower water content in the source of MEC basalts. Calbuco andesites formed from basaltic parents similar to Osorno basalts, by moderate pressure crystallization of a hornblende-bearing assemblage accompanied by crustal assimilation. Hornblende stability in the Calbuco andesites was promoted by the assimilation of hydrous metasedimentary crustal rocks, which are also an appropriate endmember for isotopic trends, together with magma storage at mid-crustal depths. The unique characteristics of Calbuco volcano, i.e. the stability of hornblende at andesitic SiO2 contents, low 143Nd/144Nd and high 87Sr/86Sr, and abundant crustal xenoliths, provide evidence for crustal assimilation that is not apparent at more northerly volcanoes in the SSVZ. 相似文献
118.
The increasing impact of disasters at local,national,regional and global scales in recent decades has provided enough evidence to urgently direct attention towards the necessity of disaster risk reduction and management,and this requires knowledge.Knowledge without communication is barren,and to communicate the risk of disaster it is necessary to understand the perception of the people at risk.In particular,this paper deals with the necessity to delineate strategies of risk communication in pursuance of risk knowledge as a core of disaster risk reduction and management,especially in mountain areas of developing countries.To portray this issue,an analysis of landslide risk perception in terms of experience,landslide risk awareness,exposure,preparedness,and risk communication and trust was undertaken in the municipality of Teziutlán,Puebla,Mexico,an area that has been affected for several decades by episodes of mass movement.Analysis of the responses to a risk perception questionnaire has offered valuable insights in terms of the information and knowledge most required by the people living in the area of interest,in order to devise a realistic and functional strategy to communicate the risk of a landslide disaster.This includes better understanding of controlling factorsand drivers of this risk,and the establishment of potential trusted sources of risk communication.Beyond considering practical matters of risk assessment and management,risk perception and communication can increase the resilience of vulnerable people,and can enhance capacity building for present and future generations. 相似文献
119.
B. Oliva-Urcia A. Moreno M. Leunda B. Valero-Garcés P. González-Sampériz G. Gil-Romera M. P. Mata HORDA Group 《Journal of Paleolimnology》2018,59(3):349-371
Sedimentological, geochemical and magnetic data in a ~ 7-m sequence from Marboré Lake (2612 m asl, central Pyrenees) provide information about environmental variability since the last glacier retreat (14.6 cal ka BP) in high-altitude Pyrenean environments. The sediment sequence is composed of millimeter- to centimeter-thick rhythmites made of finer greyish laminae and coarser-grain, carbonate-bearing laminae arranged in varied patterns throughout the sequence. Finer laminae are interpreted as deposition during periods of predominantly ice-covered conditions, whereas coarser, carbonate-bearing sediments reflect periods of higher runoff. The age model, based on 13 14C dates and a reservoir effect assessed with 210Pb and 137Cs, is coherent with known synchronous vegetation changes across the Pyrenees. Warmer intervals such as GI-1 (14.6–12.8 cal ka BP, Bølling/Allerød period), 10.4–8.2 cal ka BP in the Early Holocene, 7.5–5.2 cal ka BP in the Mid Holocene and the Medieval Climate Anomaly (AD 900–1300), are characterized by peaks in productivity and higher carbonate preservation. Deposition during colder periods such as GS-1 (12.8–11.7 cal ka BP), the Neoglacial (ca. 5.2–3.5 cal ka BP) and the Little Ice Age (last 400 years) show an increase in finer laminae. The presence of magnetite throughout the whole section suggests that Marboré Lake maintained predominantly oxic conditions since its formation. Changes in magnetic properties and the increase in magnetite from 3.5 cal ka BP to present, however, indicate a more oxic environment at the lake bottom during the last few millennia. The occurrence of Pb concentration peaks in sediments of Roman and modern age demonstrates the global distribution of heavy metal deposition, even into high-mountain lakes. 相似文献