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31.
Stella Nordhagen Dan Calverley Chris Foulds Laura O’Keefe Xinfang Wang 《Climatic change》2014,125(2):149-162
For research to positively impact society, it must be scientifically credible. The researcher plays a key role in establishing and maintaining credibility, particularly in the climate change field. This paper provides a structure for relating the credibility of researchers themselves to that of research outputs, analysing ‘researcher credibility’ with reference to three overlapping domains: personal, professional, and public. The researcher’s role in each domain is considered in a reflexive way, examining the research process and the researcher’s actions. Varied definitions of researcher credibility and possible means to achieve it in each domain are discussed, drawing on relevant cross-disciplinary literature. We argue that, in certain contexts, the actions of researchers can have a direct impact on the credibility of their research. There is scope for broadening researcher credibility to include more public-oriented behaviours. This, however, may be contentious and problematic: potential conflicts exist between public action and professional credibility, with the latter usually taking precedence. By contrast, though personal action/inaction rarely affects professional credibility, researchers’ personal behaviours may influence public perceptions of research credibility and the importance of addressing climate change. 相似文献
32.
33.
Andrea I. Pasquini Stella M. Formica Gabriela A. Sacchi 《Environmental Earth Sciences》2012,65(2):453-467
Suquía River is a medium-sized hydrological system (basin area of ~7,700 km2) that supplies fresh water to Córdoba city, a town of ~1,500,000 inhabitants in central Argentina. This paper examines the
present-day hydrochemistry of Suquía River urban catchment analyzing its major and minor dissolved components, and the nutrients
variability by means of QUAL-2K modeling software. The Suquía River has bicarbonate-type waters upstream the city and sulfate-type
waters right downstream, whereas they exhibit a mixed-to-alkali-type cationic composition. The seasonal analysis of its major
dissolved constituents clearly showed a dilution process during the wet season (i.e. austral summer). In the last 20 years,
the Suquía River has modified its anionic composition, now showing higher relative concentrations of SO4
2− as a consequence of urban activities. However, trace elements dissolved concentrations do not evidence a strong pollution
effect. Nutrients [nitrogen species, total phosphorous (TP)] and related parameters, such as biochemical oxygen demand (BOD),
and dissolved oxygen (DO), evidence a clear influence of human activities. The QUAL-2K model was used to evaluate the spatial
behavior of selected nutrients and associated variables, (i.e. TP, N–NH4
+, N–NO3
−, DO, BOD). Nutrient concentrations are affected by point sources of contaminants, particularly domestic waste and sewage,
as well as by diffuse agricultural pollution. A calibrated QUAL-2K modeling exercise clearly shows the impact of the Córdoba
city’s municipal wastewater treatment plant on the Suquía River water quality. 相似文献
34.
This paper focuses on the historical range of variability of landslide activity and its relation to climate in the Aconcagua Park, Argentina. Landslide frequency data are obtained through historic compilation, including the review of more than 85 data sources and personal interviews with members of the local community. Based on these records, the study analyzes major landslide triggering mechanisms and evaluates the role of climate. Slope instability in Aconcagua Park appears to be mainly forced by the melting of snow accumulated during the winter season, which in turn promotes soil saturation and landslide occurrence the following spring–summer (December–February). This finding is supported by a strong correlation between landslides and stream flows of Andean rivers. These peaks occur during warmer seasons, fed by snow and ice‐glacier melting. In contrast, the correlation between landslide frequency and precipitation (diary/accumulative/monthly/annual) is less certain; and the relationship of landslide to temperature records (mean annual temperature/mean temperature during November–February period) is weak. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
35.
Eran O. Ofek Stella Seitz Felix Klein 《Monthly notices of the Royal Astronomical Society》2008,389(1):311-314
Highly magnified lensed galaxies allow us to probe the morphological and spectroscopic properties of high-redshift stellar systems in great detail. However, such objects are rare, and there are only a handful of lensed galaxies that are bright enough for a high-resolution spectroscopic study with current instrumentation. We report the discovery of a new massive lensing cluster, SDSS J120923.7+264047, at z = 0.558. Present around the cluster core, at angular distances of up to ∼40 arcsec, are many arcs and arc candidates, presumably due to lensing of background galaxies by the cluster gravitational potential. One of the arcs, 21 arcsec long, has an r -band magnitude of 20, making it one of the brightest known lensed galaxies. We obtained a low-resolution spectrum of this galaxy, using the Keck-I telescope, and found it is at redshift of z = 1.018. 相似文献
36.
Carolina Lauro Stella M. Moreiras Sebastian Junquera Ivan Vergara Rafael Toural Johannes Wolf Ruben Tutzer 《Environmental Earth Sciences》2017,76(5):213
The Central-West region of Argentina was seriously affected by a series of convective summer storms on January–February of 2013 generating many debris flows and rockfall in the Central Andes mountain regions. In particular, the unreported 8th February event caused the sad death of a 10-year-old child being completely ignored by society and local authorities. Despite this, meteorological conditions associated with this event and further episodes were rarely measured and determined mainly due to scarce meteorological stations in Andean mountain areas. In this paper, meteorological data from CMORPH algorithm and measurements of surrounding gauges were analyzed for estimating the triggering precipitation value of this event. As well, the particular debris flow channeled into the main branch of the Amarilla gully in the Agua Negra valley was geomorphologically described. The amount of precipitation associated with this debris flow was 5.5 and 13.2 mm accumulated previous to the event. This violent debris flow was generated in a talus zone in a periglacial environment located just below a covered rock glacier. However, the influence of the permafrost thawing in this process is not feasible. The altitude of the 0 °C isotherm was lower during the previous days of the event, and no monitoring on permafrost is available for this area. The volume of removed mass was estimated in 5 × 104 m3, and the mean velocity was 35 km/h. Boulders of 4 m diameter were found in the source area, while the deposit is up to 75% sandy with clasts that hardly exceed 10 cm in the alluvial fan distal part. Herein the main objective is to advice about the probable catastrophic impact of similar events in the future. These findings could be useful for hazard remediation, mitigation, and prevention plans for the Agua Negra international pass under construction. 相似文献
37.
Approximated similarity solutions are given for the problem of electric field penetration into a semi-infinite plasma with nonlinear saturating conductivity (exponential type), using the two point quasifractional approximants method. 相似文献
38.
Architectural heritage comprises one of the most important elements of mountain settlements in Greece. It holds high cultural value, represents the tangible continuation of the past and forms the unique character and identity of each mountain region. Yet, controversy regarding funding for its preservation often arises. In this paper, we used two Contingent Valuation surveys to estimate the social benefit deriving from protecting the traditional architecture in the mountainous village of Sirako and, through it, to examine perceptions and attitudes of local residents and visitors. Research findings revealed a strong social will in favor of the good’s protection followed by high percentages of positive willingness to pay (WTP). However, WTP is significantly higher among residents. Cultural heritage value, of the good, appears to prevail, along with the environmental one. However, both residents and visitors pointed out that local heritage, if well-preserved, will boost tourism development. Residents appeared to better recognize the true level of architectural decay, expressed higher apprehension for its protection and were willing to pay higher amount of money. Tourists, on the other side, expressed high satisfaction for their visit, appreciated the beauty and serenity emerging from local built and natural environment and spent several days visiting the surrounding area. The longer they stayed and got familiar with the village, the more willing they were to contribute to local heritage’s protection. Percentages reflecting indifference for protecting architecture were extremely low. Yet, they were higher among tourists. Traditional architecture is considered as public good; an opinion resulting in an important percentage of visitors stating that national government should provide the necessary funding. In addition, the architecture appears to hold a high level of topicality. Those descending from Sirako or emotionally connected to it, of both social groups, turned out to be more concerned about the good and with a stronger sense of responsibility for it. Use-value of the good holds high economic value, as well, while higher percentages of zero WTP appeared among non-users. Research findings revealed social attitudes and perceptions on what constitutes architectural heritage, in its cultural and economic frame. If taken under consideration, they may form useful drivers for local, heritage-based, sustainable development. 相似文献
39.
Marc Mayes Kelly K. Caylor Michael Bliss Singer John C. Stella Dar Roberts Pamela Nagler 《水文研究》2020,34(25):4884-4903
Semi-arid riparian woodlands face threats from increasing extractive water demand and climate change in dryland landscapes worldwide. Improved landscape-scale understanding of riparian woodland water use (evapotranspiration, ET) and its sensitivity to climate variables is needed to strategically manage water resources, as well as to create successful ecosystem conservation and restoration plans for potential climate futures. In this work, we assess the spatial and temporal variability of Cottonwood (Populus fremontii)-Willow (Salix gooddingii) riparian gallery woodland ET and its relationships to vegetation structure and climate variables for 80 km of the San Pedro River corridor in southeastern Arizona, USA, between 2014 and 2019. We use a novel combination of publicly available remote sensing, climate and hydrological datasets: cloud-based Landsat thermal remote sensing data products for ET (Google Earth Engine EEFlux), Landsat multispectral imagery and field data-based calibrations to vegetation structure (leaf-area index, LAI), and open-source climate and hydrological data. We show that at landscape scales, daily ET rates (6–10 mm day−1) and growing season ET totals (400–1,400 mm) matched rates of published field data, and modelled reach-scale average LAI (0.80–1.70) matched lower ranges of published field data. Over 6 years, the spatial variability of total growing season ET (CV = 0.18) exceeded that of temporal variability (CV = 0.10), indicating the importance of reach-scale vegetation and hydrological conditions for controlling ET dynamics. Responses of ET to climate differed between perennial and intermittent-flow stream reaches. At perennial-flow reaches, ET correlated significantly with temperature, whilst at intermittent-flow sites ET correlated significantly with rainfall and stream discharge. Amongst reaches studied in detail, we found positive but differing logarithmic relationships between LAI and ET. By documenting patterns of high spatial variability of ET at basin scales, these results underscore the importance of accurately accounting for differences in woodland vegetation structure and hydrological conditions for assessing water-use requirements. Results also suggest that the climate sensitivity of ET may be used as a remote indicator of subsurface water resources relative to vegetation demand, and an indicator for informing conservation management priorities. 相似文献
40.