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1.
The existing United Nations Framework Convention on Climate Change (UNFCCC) has failed to deliver the rate of low-carbon technology transfer (TT) required to curb GHG emissions in developing countries. This failure has exposed the limitations of universalism and renewed interest in bilateral approaches to TT. Gaps are identified in the UNFCCC approach to climate change TT: missing links between international institutions and the national enabling environments that encourage private investment; a non-differentiated approach for (developing) country and technology characteristics; and a lack of clear measurements of the volume and effectiveness of TTs. Evidence from econometric literature and business experience on climate change TT is reviewed, so as to address the identified pitfalls of the UNFCCC process. Strengths and weaknesses of different methodological approaches are highlighted. International policy recommendations are offered aimed at improving the level of emission reductions achieved through TT. 相似文献
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Katy Mee Jennie S. Gilbert David W. McGarvie José A. Naranjo Malcolm S. Pringle 《Bulletin of Volcanology》2009,71(8):933-952
Nevados de Chillán Volcanic Complex, central Chile, has been active for at least 640 ka—a period spanning a number of glacial
and interglacial periods. Geologic mapping, radiometric dating and geochemical analysis have identified six new volcanic units
and produced four new 40Ar/39Ar ages for Cerro Blanco, the northern subcomplex of Nevados de Chillán volcano. Compositions range from dacite to basaltic-andesite
and a new geologic map is presented. Examination of lava fracture structures on both newly mapped lavas and those mapped during
previous studies has enabled interpretations of former eruptive environments. Palaeoenvironment reconstructions, combined
with 40Ar/39Ar ages and comparison with the marine oxygen isotope record, show that at least three phases of volcanic activity have occurred
during the evolution of Cerro Blanco: (1) a constructive, pre-caldera collapse period; (2) a period of caldera formation and
collapse; and (3) a constructive period of dome growth forming the modern day volcanic centre. This style of volcanic evolution,
whereby large-scale caldera collapse is followed by growth of a new stratocone is common at Andean volcanoes. 相似文献
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Role of cryptic amphibole crystallization in magma differentiation at Hudson volcano, Southern Volcanic Zone, Chile 总被引:1,自引:0,他引:1
David J. Kratzmann Steven Carey Roberto A. Scasso Jose-Antonio Naranjo 《Contributions to Mineralogy and Petrology》2010,159(2):237-264
Hudson volcano (Chile) is the southern most stratovolcano of the Andean Southern Volcanic Zone and has produced some of the
largest Holocene eruptions in South America. There have been at least 12 recorded Holocene explosive events at Hudson, with
the 6700 years BP, 3600 years BP, and 1991 eruptions the largest of these. Hudson volcano has consistently discharged magmas
of similar trachyandesitic and trachydacitic composition, with comparable anhydrous phenocryst assemblages, and pre-eruptive
temperatures and oxygen fugacities. Pre-eruptive storage conditions for the three largest Holocene events have been estimated
using mineral geothermometry, melt inclusion volatile contents, and comparisons to analogous high pressure experiments. Throughout
the Holocene, storage of the trachyandesitic magmas occurred at depths between 0.2 and 2.7 km at approximately ~972°C (±25)
and log fO2 −10.33–10.24 (±0.2) (one log unit above the NNO buffer), with between 1 and 3 wt% H2O in the melt. Pre-eruptive storage of the trachydacitic magma occurred between 1.1 and 2.0 km, at ~942°C (±26) and log fO2 −10.68 (±0.2), with ~2.5 wt% H2O in the melt. The evolved trachyandesitic and trachydacitic magmas can be derived from a basaltic parent primarily via fractional
crystallization. Entrapment pressures estimated from plagioclase-hosted melt inclusions suggest relatively shallow levels
of crystallization. However, trace element data (e.g., Dy/Yb ratio trends) suggests amphibole played an important role in
the differentiation of the Hudson magmas, and this fractionation is likely to have occurred at depths >6 km. The absence of
a garnet signal in the Hudson trace element data, the potential staging point for differentiation of parental mafic magmas
[i.e., ~20 km (e.g., Annen et al. in J Petrol 47(3):505–539, 2006)], and the inferred amphibolite facies [~24 km (e.g., Rudnick and Fountain in Rev Geophys 33:267–309, 1995)] combine to place some constraint on the lower limit of depth of differentiation (i.e., ~20–24 km). These constraints suggest
that differentiation of mantle-derived magmas occurred at upper-mid to lower crustal levels and involved a hydrous mineral
assemblage that included amphibole, and generated a basaltic to basaltic andesitic composition similar to the magma discharged
during the first phase of the 1991 eruption. Continued fractionation at this depth resulted in the formation of the trachyandesitic
and trachydacitic compositions. These more evolved magmas ascended and stalled in the shallow crust, as suggested by the pressures
of entrapment obtained from the melt inclusions. The decrease in pressure that accompanied ascent, combined with the potential
heating of the magma body through decompression-induced crystallization would cause the magma to cross out of the amphibole
stability field. Further shallow crystallization involved an anhydrous mineral assemblage and may explain the lack of phenocrystic
amphibole in the Hudson suite. 相似文献
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Biological quality in a bay affected by man's activities was evaluated by means of the composition of assemblages of sponges and ascidians. Our results showed that the structure of these two groups of filter-feeders aided in discriminating between undisturbed and disturbed areas, establishing different "environmental health categories" from moderately to strongly disturbed areas, and in ascertaining the extension of the area of each "health category". We were able to divide the bay into four zones based on type of disturbance or anthropogenic source: (1) stations free of any source of disturbance, (2) stations under moderate disturbance, located close to industrial ports, millworks, etc., (3) stations that are under the direct influence of industrial wastes such as a power station and oil refinery, and (4) stations near strongly disturbed areas, influenced directly by harmful steelworks activities. We differentiated clearly between four large species assemblages, and related the composition of these assemblages to different kinds of disturbances. Thus, these species could be used to manage the marine environment in this bay by comparing the observed fauna, with expected fauna in an unstressed site. Moreover, the joint presence of the sponge Cliona vastifica and tunicate Policitor adriaticum seems always to indicate a more or less pristine environmental situation, functioning as bioindicators of normal conditions. We think that the use of specific bioindicators for monitoring disturbance is a valid tool to establish baselines to predict impacts associated with industrial development in many marine ecosystems. The advantages to monitoring communities on hard rocks versus sandy or muddy bottoms are also commented upon. 相似文献
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A Bayesian hierarchical spatio-temporal model for extreme rainfall in Extremadura (Spain) 总被引:1,自引:1,他引:0
A statistical study was made of the temporal trend in extreme rainfall in the region of Extremadura (Spain) during the period 1961–2009. A hierarchical spatio-temporal Bayesian model with a GEV parameterization of the extreme data was employed. The Bayesian model was implemented in a Markov chain Monte Carlo framework that allows the posterior distribution of the parameters that intervene in the model to be estimated. The results show a decrease of extreme rainfall in winter and spring and a slight increase in autumn. The uncertainty in the trend parameters obtained with the hierarchical approach is much smaller than the uncertainties obtained from the GEV model applied locally. Also found was a negative relationship between the NAO index and the extreme rainfall in Extremadura during winter. An increase was observed in the intensity of the NAO index in winter and spring, and a slight decrease in autumn. 相似文献
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M. D.?AlbaEmail author M. A.?Castro M.?Naranjo A. C.?Perdigón 《Physics and Chemistry of Minerals》2004,31(4):195-202
The main objective of this paper is to apply an NMR-based methodology to clay minerals that provides resolution enhancement in 27Al NMR spectra, permitting the differentiation of aluminum ions with one same coordination number, but with different chemical environments. For this purpose, we have performed two-dimensional 1H27Al cross-polarization experiments, which facilitate the identification of the different aluminum crystallographic sites by means of the nature of the proton polarization source. For the development of this methodology, we have carried out a systematic study of a set of well-characterized 2:1 phyllosilicates with aluminum in different crystallographic sites. The structural locations of aluminum in the selected layered silicates have been established unequivocally. Once the correlation between all different aluminum and proton sites in smectite was well established, an unknown material was examined, the utility of this methodology being illustrated. This methodology can be applied to a great variety of materials, such as zeolites, ALPOs and mesoporous aluminosilicates, in which a precise determination of the aluminum location is demanded. 相似文献
10.
Oscar Vicente Monica Boscaiu Miguel ngel Naranjo Elena Estrelles Jos María Bells Pilar Soriano 《Journal of Arid Environments》2004,58(4):705
General responses to salt stress have been investigated in the halophyte Plantago crassifolia. Seed germination was strongly inhibited by NaCl, although seed viability and germination capacity were not affected by salt pre-treatments. A concentration-dependent inhibition of plant growth was observed in the presence of NaCl, which was accompanied by the accumulation of Na+ ions in the leaves, as determined by cation exchange HPLC. A 20-fold increase of proline content in leaves was observed when plants were treated with 500 m
NaCl, suggesting a protective role against high salinity stress for this amino acid, whose possible mechanism of action is discussed. 相似文献