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21.
Paul?Martin?HolmEmail author Nina?S?ager Charlotte?Thorup?Dyhr Mia?Rohde?Nielsen 《Contributions to Mineralogy and Petrology》2014,167(5):1004
Mafic basaltic-andesitic volcanic rocks from the Andean Southern Volcanic Zone (SVZ) exhibit a northward increase in crustal components in primitive arc magmas from the Central through the Transitional and Northern SVZ segments. New elemental and Sr–Nd-high-precision Pb isotope data from the Quaternary arc volcanic centres of Maipo (NSVZ) and Infernillo and Laguna del Maule (TSVZ) are argued to reflect mainly their mantle source and its melting. For the C-T-NSVZ, we identify two types of source enrichment: one, represented by Antuco in CSVZ, but also present northward along the arc, was dominated by fluids which enriched a pre-metasomatic South Atlantic depleted MORB mantle type asthenosphere. The second enrichment was by melts having the characteristics of upper continental crust (UCC), distinctly different from Chile trench sediments. We suggest that granitic rocks entered the source mantle by means of subduction erosion in response to the northward increasingly strong coupling of the converging plates. Both types of enrichment had the same Pb isotope composition in the TSVZ with no significant component derived from the subducting oceanic crust. Pb–Sr–Nd isotopes indicate a major crustal compositional change at the southern end of the NSVZ. Modelling suggests addition of around 2 % UCC for Infernillo and 5 % for Maipo. 相似文献
22.
Anna Scolobig Nadejda Komendantova Anthony Patt Charlotte Vinchon Daniel Monfort-Climent Mendy Begoubou-Valerius Paolo Gasparini Angela Di Ruocco 《Natural Hazards》2014,73(3):1523-1545
Technical and institutional capacities are strongly related and must be jointly developed to guarantee effective natural risk governance. Indeed, the available technical solutions and decision support tools influence the development of institutional frameworks and disaster policies. This paper analyses technical and institutional capacities, by providing a comparative evaluation of governance systems in Italy and France. The focus is on two case studies: Naples and Guadeloupe. Both areas are exposed to multiple hazards, including earthquakes, volcanic eruptions, landslides, floods, tsunamis, fires, cyclones, and marine inundations Cascade and conjoint effects such as seismic swarms triggered by volcanic activity have also been taken into account. The research design is based on a documentary analysis of laws and policy documents informed by semi-structured interviews and focus groups with stakeholders at the local level. This leads to the identification of three sets of governance characteristics that cover the key issues of: (1) stakeholders and governance level; (2) decision support tools and mitigation measures; and (3) stakeholder cooperation and communication. The results provide an overview of the similarities and differences as well as the strengths and weaknesses of the governance systems across risks. Both case studies have developed adequate decision support tools for most of the hazards of concern. Warning systems, and the assessment of hazards and exposure are the main strengths. While technical/scientific capacities are very well developed, the main weaknesses involve the interagency communication and cooperation, and the use and dissemination of scientific knowledge when developing policies and practices. The consequences for multi-risk governance are outlined in the discussion. 相似文献
23.
Climate change and mental health: an exploratory case study from Rigolet, Nunatsiavut, Canada 总被引:1,自引:0,他引:1
Ashlee Cunsolo Willox Sherilee L. Harper James D. Ford Victoria L. Edge Karen Landman Karen Houle Sarah Blake Charlotte Wolfrey 《Climatic change》2013,121(2):255-270
As the impacts from anthropogenic climate change are increasing globally, people are experiencing dramatic shifts in weather, temperature, wildlife and vegetation patterns, and water and food quality and availability. These changes impact human health and well-being, and resultantly, climate change has been identified as the biggest global health threat of the 21st Century. Recently, research is beginning to indicate that changes in climate, and the subsequent disruption to the social, economic, and environmental determinants of health, may cause increased incidences and prevalence of mental health issues, emotional responses, and large-scale sociopsychological changes. Through a multi-year, community-led, exploratory case study conducted in Rigolet, Nunatsiavut, Labrador, Canada, this research qualitatively explores the impacts of climate change on mental health and well-being in an Inuit context. Drawing from 67 in-depth interviews conducted between January 2010 and October 2010 with community members and local and regional health professionals, participants reported that changes in weather, snow and ice stability and extent, and wildlife and vegetation patterns attributed to climate change were negatively impacting mental health and well-being due to disruptions in land-based activities and a loss of place-based solace and cultural identity. Participants reported that changes in climate and environment increased family stress, enhanced the possibility of increased drug and alcohol usage, amplified previous traumas and mental health stressors, and were implicated in increased potential for suicide ideation. While a preliminary case study, these exploratory findings indicate that climate change is becoming an additional mental health stressor for resource-dependent communities and provide a baseline for further research. 相似文献
24.
The principle of common but differentiated responsibilities and respective capabilities (CBDRC) captures the idea that it is the common responsibility of states to protect and restore the environment but that the levels and forms of states’ individual responsibilities may be differentiated according to their own national circumstances. This principle has shaped the evolution of the climate regime and has played an important role in promoting compromise and agreement. It is argued that some twenty years after the adoption of the United Nations Framework Convention on Climate Change (UNFCCC), the principle of CBDRC remains as relevant as ever. The practice of Parties under the regime and, most recently, the concerted efforts to shape and flesh out the meaning of the principle, underscore the central role that it plays. At the same time, the binary understanding of CBDRC in the Kyoto Protocol is being replaced with a more nuanced, multifaceted understanding. The evolving interpretation of CBDRC is considered, and its continued relevance as the nucleus of a global burden-sharing regime for addressing climate change is demonstrated. Policy relevance The development of a common understanding of the principle of CBDRC is essential for the burden sharing and responsibilities under a future climate agreement. The CBDRC principle captures the idea that it is the common responsibility of states to protect and restore the environment, but that the levels and forms of states’ individual responsibilities may be differentiated according to their own national circumstances. This article informs the international climate change negotiations by considering the development of the principle of CBDRC under the UNFCCC over time. It is concluded that, although there has been a significant shift in how the principle is understood, it remains crucial to the integrity and stability of the climate regime. 相似文献
25.
Summary. The 1985 Lithoprobe East profiles resolve deep crustal structure of the Grand Banks off eastern Canada. Basins are 7 to 20 km deep, and bounded by major faults traceable to Mono depth. The lower crust is reflective along much of the survey, and the top of this reflective layer has a variable depth. Prominent and often surprisingly flat Mono reflections are observed. Puzzling rotated fault blocks are imaged at the continent-ocean transition. 相似文献
26.
Dan?HammarlundEmail author Svante?Bj?rck Bj?rn?Buchardt Charlotte T.?Thomsen 《Journal of Paleolimnology》2005,34(4):471-480
Highly resolved sediment stratigraphic and stable isotope records from a lake in south-central Sweden give evidence of relatively humid summers during the wide-spread cold event at c. 8200 cal. BP. A transient lake-level rise led to increased catchment erosion followed by enhanced phytoplankton production and disturbance of the Chara-dominated algal community. An associated increase in the deposition of organic material resulted in hypolimnetic oxygen deficit and methane formation as inferred from elevated sulphur content of the sediments and strong depletion in 13C of bulk organic material. In combination with dry and cold winter conditions as revealed by other proxy records, these data suggest the development of a strongly seasonal climate in northwestern Europe in response to altered atmospheric circulation at this stage. Enhanced zonal circulation with frequent cyclonic activity and increased effective humidity probably characterized the summer climate of southern and central Scandinavia, consistent with conditions inferred for continental Europe. In contrast, the winter climate was dominated by blocking high-pressure circulation, giving rise to cold and dry conditions. 相似文献
27.
The late‐stage evolution of the southern central Pyrenees has been well documented but controversies remain concerning potential Neogene acceleration of exhumation rates and the influence of tectonic and/or climatic processes. A popular model suggests that the Pyrenees and their southern foreland were buried below a thick succession of conglomerates during the Oligocene, when the basin was endorheic. However, both the amount of post‐orogenic fill and the timing of re‐excavation remain controversial. We address this question by revisiting extensive thermochronological datasets of the Axial Zone. We use an inverse approach that couples the thermo‐kinematic model Pecube and the Neighbourhood inversion algorithm to constrain the history of exhumation and topographic changes since 40 Ma. By comparison with independent geological data, we identified a most probable scenario involving rapid exhumation (>2.5 km Myr?1) between 37 and 30 Ma followed by a strong decrease to very slow rates (0.02 km Myr?1) that remain constant until the present. Therefore, the inversion does not require a previously inferred Pliocene acceleration in regional exhumation rates. A clear topographic signal emerges, however: the topography has to be infilled by conglomerates to an elevation of 2.6 km between 40 and 29 Ma and then to remain stable until ca. 9 Ma. We interpret the last stage of the topographic history as recording major incision of the southern Pyrenean wedge, due to the Ebro basin connection to the Mediterranean, well before previously suggested Messinian ages. These results thus demonstrate temporally varying controls of different processes on exhumation: rapid rock uplift in an active orogen during late Eocene, whereas base‐level changes in the foreland basin control the post‐orogenic evolution of topography and exhumation in the central Pyrenees. In contrast, climate changes appear to play a lesser role in the post‐orogenic topographic and erosional evolution of this mountain belt. 相似文献
28.
Tilo Usbeck Peter Waldner Matthias Dobbertin Christian Ginzler Christian Hoffmann Flurin Sutter Charlotte Steinmeier Richard Volz Gustav Schneiter Martine Rebetez 《Theoretical and Applied Climatology》2012,108(3-4):451-462
This study compares the surface wind speed and forest damage data of two exceptionally severe winter storms, Vivian 1990 and Lothar 1999. The study area comprises the region that suffered damage in Switzerland. The wind speed data were derived from simulations of MeteoSwiss (Federal Office of Meteorology and Climatology), measurements during the storm periods and expert analyses of the data. The remotely sensed forest damage data were provided by the Federal Office for the Environment and the forest cover data by Swiss Federal Statistical Office. We compared data on the peak gust and maximum average wind speed, with data on the spatially related forest area and forest damage area, and found some clear differences in the correlations between the different wind data and forest damage. Our results point generally to the damage-causing role of near-surface gusts at maximum wind speeds during the storm. These tended to be spatially distributed on a fine scale. In only a few cases were the results statistically significant. However, these results could probably be improved with better wind data. For example, gust measurements spatially closer to forests or simulations of gusts at maximum wind speed could be produced with a spatially higher resolution. 相似文献
29.
30.
Solubility of Pt in sulphide mattes: Implications for the genesis of PGE-rich horizons in layered intrusions 总被引:1,自引:0,他引:1
Raúl O.C. Fonseca Ian H. Campbell Hugh St. C. ONeill Charlotte M. Allen 《Geochimica et cosmochimica acta》2009,73(19):5764-5777
The partitioning of Pt in sulphide melt (matte) has been studied as a function of fS2 and fO2 at 1200 and 1300 °C. The results show that the solubility of Pt in mattes increases strongly with increasing fS2 and decreases weakly with increasing fO2. The increase in Pt solubility with increasing fS2 is attributed to Pt dissolving in the melt as a sulphide species and the weak inverse dependence of Pt solubility on fO2 to the diluting effect of increasing O in the melt at high fO2. These results, coupled with measurements of Pt solubility in silicate melts taken from the literature, allow the calculation of Pt matte/silicate-melt partition coefficients () for a range of conditions pertinent to the formation of Pt-rich horizons in layered intrusions. The calculated values range between 107 and 1011, depending on fO2 and fS2, several orders of magnitude higher than previously published values. Our preferred value for for conditions appropriate to the Merensky Reef is 107 and for the Stillwater Pt-rich horizon 108. The new results are consistent with the magmatic hypothesis for Pt-rich horizons in layered intrusions. 相似文献