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11.
The PRUDENCE project has generated a set of spatially and temporally high-resolution climate data, which provides new opportunities for assessing the impacts of climate variability and change on economic and human systems in Europe. In this context, we initiated the development of new approaches for linking climate change information and economic studies. We have considered a number of case studies that illustrate how linkages can be established between geographically detailed climate data and economic information. The case studies included wheat production in agriculture, where regional climate data has been linked to farm enterprise data in an integrated model of physical conditions, production inputs and outputs, and farm management practices. Similarly, temperature data were used to assess consequences of extreme heat and excess mortality in urban areas. We give an introduction of an analytical approach for assessing economic impacts of climate change and discuss how economic concepts and valuation paradigms can be applied to climate change impact evaluation. A number of methodological difficulties encountered in economic assessments of climate change impacts are described and a number of issues related to social and private aspects of costs are highlighted. It is argued that, in particular, detailed climate information matters in relation to understanding how private agents react to observed climate data.  相似文献   
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A large number of individual enstatite crystals of the gas-rich aubrites Khor Temiki, Staroe Pesyanoe and Bustee was analyzed for implanted helium and for steep gradient ion tracks in order to investigate the relation between solar flare irradiation and solar wind implantation with extreme local resolution. Irradiated and non-irradiated crystals coexist within the gas-rich phases of the aubrites investigated. Statistically in a given meteorite the proportion of crystals with implanted solar wind is similar to the proportion of solar flare irradiated crystals. It varies from aubrite to aubrite in the sequence of their bulk contents of trapped rare gases.For nine enstatites, tracks and rare gases were subsequently measured within the same crystal. The results support the intimate association of solar flare tracks and implanted He. The4He-surface concentrations of irradiated crystals vary between <5 × 10?7 and 10?4 cm3 STP/cm2.The absence of saturation effects together with the low degree of elemental gas fractionation indicates very short solar wind exposure times (< 100 yr) rather than strong diffusion losses. The evidence from tracks and rare gases can be understood in terms of an early simultaneous irradiation of aubritic crystals by solar wind and solar flare particles on top of a regolith-covered parent body.  相似文献   
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Journal of Paleolimnology -  相似文献   
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Phytoplankton community and environmental factors have been investigated in the eutrophic and shallow Lake Arresø in Denmark. The lake was completely mixed, except when ice-covered. Nitrogen and phosphorus were never primarily limiting phytoplankton growth and nitrogen-fixation was of minor importance. Phytoplankton community comprised mainly of chloroccocal green algae. Various possible reasons why chlorococcal green algae are so successful in this lake are discussed.  相似文献   
16.
An Integrated Assessment of changes in the thermohaline circulation   总被引:1,自引:0,他引:1  
This paper discusses the risks of a shutdown of the thermohaline circulation (THC) for the climate system, for ecosystems in and around the North Atlantic as well as for fisheries and agriculture by way of an Integrated Assessment. The climate model simulations are based on greenhouse gas scenarios for the 21st century and beyond. A shutdown of the THC, complete by 2150, is triggered if increased freshwater input from inland ice melt or enhanced runoff is assumed. The shutdown retards the greenhouse gas-induced atmospheric warming trend in the Northern Hemisphere, but does not lead to a persistent net cooling. Due to the simulated THC shutdown the sea level at the North Atlantic shores rises by up to 80 cm by 2150, in addition to the global sea level rise. This could potentially be a serious impact that requires expensive coastal protection measures. A reduction of marine net primary productivity is associated with the impacts of warming rather than a THC shutdown. Regional shifts in the currents in the Nordic Seas could strongly deteriorate survival chances for cod larvae and juveniles. This could lead to cod fisheries becoming unprofitable by the end of the 21st century. While regional socioeconomic impacts might be large, damages would be probably small in relation to the respective gross national products. Terrestrial ecosystem productivity is affected much more by the fertilization from the increasing CO2 concentration than by a THC shutdown. In addition, the level of warming in the 22nd to 24th century favours crop production in northern Europe a lot, no matter whether the THC shuts down or not. CO2 emissions corridors aimed at limiting the risk of a THC breakdown to 10% or less are narrow, requiring departure from business-as-usual in the next few decades. The uncertainty about THC risks is still high. This is seen in model analyses as well as in the experts’ views that were elicited. The overview of results presented here is the outcome of the Integrated Assessment project INTEGRATION.  相似文献   
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ABSTRACT

Several hundred million people in sub-Saharan Africa are at risk of being without access to electricity by 2030 despite the ongoing work aimed at achieving the United Nations’ Sustainable Development Goal 7—sustainable energy for all. Based on qualitative interviews, quantitative surveys, observation, and participation in Kenya and Senegal between 2010 and 2018, the author aims to explain why the rate of progress is slower than intended. The findings highlight three strong hindrances: lack of affordability due to extreme poverty, mismatch between the village-level outreach of grid-based electricity systems and the geography of settlements, and lack of consideration given to gender inequality. The findings also provide new insights into the ways that decentralized small-scale solar power increasingly meets some of the shortcomings of centralized grids in addressing these three issues, even in rural areas where grids are already present. The author concludes that the ways in which village communities have combined the use of solar-powered energy with grid-supplied energy indicates the importance of the former and the need to intensify efforts to improve solar power delivery models and integrate them fully in energy sector strategies.  相似文献   
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Entanglement with plastic debris is a major cause of mortality in marine taxa, but the population-level consequences are unknown. Some seabirds collect marine debris for nesting material, which may lead to entanglement. Here we investigate the use of plastics as nesting material by northern gannets Morus bassanus and assess the associated levels of mortality. On average gannet nests contained 469.91 g (range 0-1293 g) of plastic, equating to an estimated colony total of 18.46 tonnes (range 4.47-42.34 tonnes). The majority of nesting material was synthetic rope, which appears to be used preferentially. On average 62.85 ± 26.84 (range minima 33-109) birds were entangled each year, totalling 525 individuals over eight years, the majority of which were nestlings. Although mortality rates are high, they are unlikely to have population-level effects. The use of synthetic fibres as nesting material is a common strategy among seabirds, but the impacts of entanglement warrants further investigation.  相似文献   
20.
A field and petro-chemical classification of felsic magmatic phases (FMPs) at the world-class Cantung W skarn deposit was undertaken to document the evolution of magmatism and the relationships between different FMPs, metasomatism, and mineralization. Early FMPs include moderately differentiated (Zr/Hf = 18–26, Ti/Zr = 14–15) biotite monzogranitic plutons and early biotite-rich granitic dykes, and compositionally similar quartz–feldspar porphyry dykes. Late, highly fractionated (Zr/Hf = 8–17, Ti/Zr = 3–13) FMPs sourced from a deeper monzogranitic intrusion include: (1) leucocratic biotite- or tourmaline-bearing dykes derived from localized entrapments of residual magma; and, (2) sub-vertical NE-trending aplitic dykes derived from a larger segregation of residual fluid- and incompatible element-enriched magma. The aplitic dykes have textures, morphologies, spatial associations, and a pervasive calcic metasomatic mineral assemblage (Ca-plagioclase + quartz or clinozoisite) indicative of syn-mineralization emplacement. Very late-stage overpressuring and initiation of sub-vertical fractures into the overlying plutonic carapace and country rocks by supercritical magmatic fluid led to an interaction with calcareous country rocks that resulted in an increased aCa2+ in the fluid and the concurrent precipitation of W skarn. Residual magma also ascended with, and quenched in equilibrium with the magmatic fluid to from the aplitic dykes, then was metasomatized by the fluid as it interacted with calcareous country rocks. Overall, highly fractionated and moderately to very highly undercooled FMPs at Cantung provide evidence for a large and evolving felsic magmatic system at depth that segregated and maintained a stable fluid- and incompatible element-enriched residual magma until the latest stages of crystallization. The detailed study of FMPs associated with magmatic-hydrothermal mineral deposits allow us to refine our understanding of these mineralizing systems and better define metallogenic and exploration models for intrusion-related mineralization.  相似文献   
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