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1.
Informal networks and resilience to climate change impacts: A collective approach to index insurance
Sara L.M. Trærup 《Global Environmental Change》2012,22(1):255-267
This article contributes to the understanding of how to proceed with the development of index-insurance in order to reach extended population coverage with the insurance. The approach is applied to an example from a region in Tanzania. One of the main coping strategies that resource-poor households rely on to manage risks related to fluctuations in income flows is risk-sharing in informal networks. An informal network is an ideal way of managing idiosyncratic shocks, but once such shocks become covariate and affect whole communities, as is the case with most climate change impacts, informal networks become insufficient since the majority of risk-sharers will be affected by the shock at the same time. This paper proposes a collective approach to index-insurance in which the members of an informal network will be insured as one insurance taker. The paper raises a conceptual argument that targeting households through existing informal networks will remove a number of prevailing barriers to the take-up of insurance and consequently the approach has the potential to increase households’ resilience to climate change impacts. The policy implications of the conclusions are significant since the number of covariate shocks is predicted to increase with climate change. 相似文献
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3.
With multiscale permeability estimation one does not select parameterization prior to the estimation. Instead, one performs a hierarchical search for the right parameterization while solving a sequence of estimation problems with an increasing parameterization dimension. In some previous works on the subject, the same refinement is applied all over the porous medium. This may lead to over-parameterization, and subsequently, to unrealistic permeability estimates and excessive computational work. With adaptive multiscale permeability estimation, the new parameterization at an arbitrary stage in the estimation sequence is such that new degrees of freedom are not necessarily introduced all over the porous medium. The aim is to introduce new degrees of freedom only where it is warranted by the data. In this paper, we introduce a novel adaptive multiscale estimation. The approach is used to estimate absolute permeability from two-phase pressure data in several numerical examples. 相似文献
4.
Ole A. Sæther 《Aquatic Sciences - Research Across Boundaries》1971,33(1):200-220
During the summer of 1966 some limnological aspects of thirteen lakes and one pond in the most northeasterly part of Norway were studied. A total of 418 taxa of algae including 104 genera, and 70 taxa of zooplankton including 46 genera are identified. The composition of the plankton in all the waters is shown to be typical for fundamentally oligotrophic lakes. A few of the lakes show some humic influence. This is in agreement with the hydrographic results from these waters (Bøyum [1]). 相似文献
5.
J. E. Olesen T. R. Carter C. H. Díaz-Ambrona S. Fronzek T. Heidmann T. Hickler T. Holt M. I. Minguez P. Morales J. P. Palutikof M. Quemada M. Ruiz-Ramos G. H. Rubæk F. Sau B. Smith M. T. Sykes 《Climatic change》2007,81(1):123-143
The uncertainties and sources of variation in projected impacts of climate change on agriculture and terrestrial ecosystems depend not only on the emission scenarios and climate models used for projecting future climates, but also on the impact models used, and the local soil and climatic conditions of the managed or unmanaged ecosystems under study. We addressed these uncertainties by applying different impact models at site, regional and continental scales, and by separating the variation in simulated relative changes in ecosystem performance into the different sources of uncertainty and variation using analyses of variance. The crop and ecosystem models used output from a range of global and regional climate models (GCMs and RCMs) projecting climate change over Europe between 1961–1990 and 2071–2100 under the IPCC SRES scenarios. The projected impacts on productivity of crops and ecosystems included the direct effects of increased CO2 concentration on photosynthesis. The variation in simulated results attributed to differences between the climate models were, in all cases, smaller than the variation attributed to either emission scenarios or local conditions. The methods used for applying the climate model outputs played a larger role than the choice of the GCM or RCM. The thermal suitability for grain maize cultivation in Europe was estimated to expand by 30–50% across all SRES emissions scenarios. Strong increases in net primary productivity (NPP) (35–54%) were projected in northern European ecosystems as a result of a longer growing season and higher CO2 concentrations. Changing water balance dominated the projected responses of southern European ecosystems, with NPP declining or increasing only slightly relative to present-day conditions. Both site and continental scale models showed large increases in yield of rain-fed winter wheat for northern Europe, with smaller increases or even decreases in southern Europe. Site-based, regional and continental scale models showed large spatial variations in the response of nitrate leaching from winter wheat cultivation to projected climate change due to strong interactions with soils and climate. The variation in simulated impacts was smaller between scenarios based on RCMs nested within the same GCM than between scenarios based on different GCMs or between emission scenarios. 相似文献
6.
The role of technology in combatting climate change through mitigation and adaptation to its inevitable impacts has been acknowledged and highlighted by the Parties to the United Nations Framework Convention on Climate Change (UNFCCC). In the developing world, this has received particular attention through the technology needs assessment (TNA) process. As Parties put forward their national pledges to combat climate change, the scarcity of resources makes it important to assess (i) whether national processes designed to tackle climate change are working together and (ii) whether existing national processes should be terminated with the initiation of new ones. This study presents an assessment of the existing TNA process and its linkages to the nationally determined contributions (NDCs) under the Paris Agreement. The conclusions stem from an assessment of the TNAs completed to date, as well as 71 NDCs from developing countries at various stages of the TNA process. The analyses show that further developing the TNAs could play a vital role in filling gaps in the existing NDCs, specifically those relating to identifying appropriate technologies, their required enabling framework conditions and preparing implementation plans for their transfer and diffusion.
Key policy insights
The full potential of the TNAs has still to be rolled out in many countries.
Developing countries can maximize the potential of their TNAs by further developing them to explicitly analyse what is needed to implement existing NDCs, including by better aligning their focus, scope and up-to-dateness with the priority sectors included in the NDCs.
Requests of developing countries for international assistance, through technology transfer, will be better guided by the completion of the TNA process.
Policies for strengthening the NDCs will benefit from the results of completed, ongoing and future TNA processes.
7.
The influence of ultraviolet light, heating, freezing and weathering on the mercury concentration in the primary feathers from Guillemot and Black Guillemot has been examined. Even within 8 months of exposure variation in mercury concentration due to either loss of mercury or weight loss of the feathers has been found to be less than 10% relative. 相似文献
8.
The Arctic is more vulnerable to climate change than are mid latitudes. Therefore, palaeolimnological studies from the High Arctic are important in providing insights into the dynamics of the climate system. Here we present a multi‐proxy study from one of the world's northernmost lakes: Bliss Lake, Peary Land, Greenland. The early Holocene (10 850–10 480 cal. a BP) is characterized by increased erosion and gradually more marine conditions. Full marine conditions developed from 10 480 cal. a BP until the lake was isolated at 7220 cal. a BP. From its marine isolation at 7220 cal. a BP Bliss Lake becomes a lacustrine environment. Evidence from geochemical proxies (δ13C and total organic carbon) suggests that warmer conditions prevailed between 7220 and 6500 cal. a BP, corresponding to the Holocene thermal maximum, and from 3300 until 910 cal. a BP. From 850 to 500 cal. a BP colder climate conditions persisted. The transition from warmer to colder climate conditions taking place around 850 cal. a BP may be associated with the transition from the Medieval Warm Period to the Little Ice Age. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
9.
Radan Květ 《GeoJournal》1994,34(4):365-370
10.
The coupled transport of mass and heat which occurs in frost heave, is described by irreversible thermodynamics. The approach is macroscopic phenomenological and thus it correlated macroscopic measurable parameters. It avoids as far as possible details about mechanism and is therefore complementary to derivations by, e.g., Everett (1961) based on microscopic models. A new derivation is given for the coupling between the transport of liquid water and the transport of heat from 0°C to the ice lens. Assumption of local equilibrium in this region is not necessary. The temperature difference over the region causes a water flux, which in turn causes a build-up of pressure gradients. 相似文献