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1.
We propose measuring vulnerability of selected outcome variables of concern (e.g. agricultural yield) to identified stressors (e.g. climate change) as a function of the state of the variables of concern relative to a threshold of damage, the sensitivity of the variables to the stressors, and the magnitude and frequency of the stressors to which the system is exposed. In addition, we provide a framework for assessing the extent adaptive capacity can reduce vulnerable conditions. We illustrate the utility of this approach by evaluating the vulnerability of wheat yields to climate change and market fluctuations in the Yaqui Valley, Mexico.  相似文献   

2.
This paper provides an overview of climate change impacts on tribal water resources and the subsequent cascading effects on the livelihoods and cultures of American Indians and Alaska Natives living on tribal lands in the U.S. A hazards and vulnerability framework for understanding these impacts is first presented followed by context on the framework components, including climate, hydrologic, and ecosystem changes (i.e. hazards) and tribe-specific vulnerability factors (socioeconomic, political, infrastructural, environmental, spiritual and cultural), which when combined with hazards lead to impacts. Next regional summaries of impacts around the U.S. are discussed. Although each tribal community experiences unique sets of impacts because of their individual history, culture, and geographic setting, many of the observed impacts are common among different groups and can be categorized as impacts on—1) water supply and management (including water sources and infrastructure), 2) aquatic species important for culture and subsistence, 3) ranching and agriculture particularly from climate extremes (e.g., droughts, floods), 4) tribal sovereignty and rights associated with water resources, fishing, hunting, and gathering, and 5) soil quality (e.g., from coastal and riverine erosion prompting tribal relocation or from drought-related land degradation). The paper finishes by highlighting potentially relevant research questions based on the five impact categories.  相似文献   

3.
Climate Change Vulnerability Assessments: An Evolution of Conceptual Thinking   总被引:25,自引:8,他引:25  
Vulnerability is an emerging concept for climate science and policy. Over the past decade, efforts to assess vulnerability to climate change triggered a process of theory development and assessment practice, which is reflected in the reports of the Intergovernmental Panel on Climate Change (IPCC). This paper reviews the historical development of the conceptual ideas underpinning assessments of vulnerability to climate change. We distinguish climate impact assessment, first- and second-generation vulnerability assessment, and adaptation policy assessment. The different generations of assessments are described by means of a conceptual framework that defines key concepts of the assessment and their analytical relationships. The purpose of this conceptual framework is two-fold: first, to present a consistent visual glossary of the main concepts underlying the IPCC approach to vulnerability and its assessment; second, to show the evolution of vulnerability assessments. This evolution is characterized by the progressive inclusion of non-climatic determinants of vulnerability to climate change, including adaptive capacity, and the shift from estimating expected damages to attempting to reduce them. We hope that this paper improves the understanding of the main approaches to climate change vulnerability assessment and their evolution, not only within the climate change community but also among researchers from other scientific communities, who are sometimes puzzled by the unfamiliar use of technical terms in the context of climate change.  相似文献   

4.
Vulnerability is a multidimensional concept associated with high uncertainty in measurement and classification. Developing a vulnerability index from the diverse and often incommensurate data that form the basis of vulnerability assessments is often a core challenge of vulnerability research. Problematically, many vulnerability indices are based on the implicit or explicit assumption that each indicator of vulnerability is of equal importance. In this paper we propose a procedure to engage constructively with the inherent subjectivity and uncertainty of assigning weights to disparate indicators used in vulnerability assessments, using common tools of multicriteria decision analysis (MCDA) and fuzzy logic. To illustrate our proposed methodology, we present a case study of rural livelihood vulnerability in the state of Tamaulipas, México. In our case study, we combine a livelihoods framework with MCDA to weigh household attributes according to their relative importance in driving household vulnerability. This approach requires the explicit articulation of the relationship of each indicator to the umbrella concept (vulnerability) as well as of each indicator to every other indicator. In recognition of the inherent uncertainties involved in assigning any particular unit of analysis to a specific vulnerability class, we use fuzzy logic to create the final categories of household livelihood vulnerability to climatic risk. Our analysis reveals how different structures of livelihood assets and activities contributes to household sensitivity and capacities in a region characterized by variable climatic conditions, stagnant incomes, increasing market stress and declining farm productivity.  相似文献   

5.
In this paper, we propose a scenario framework that could provide a scenario “thread” through the different climate research communities (climate change – vulnerability, impact, and adaptation - and mitigation) in order to support assessment of mitigation and adaptation strategies and climate impacts. The scenario framework is organized around a matrix with two main axes: radiative forcing levels and socio-economic conditions. The radiative forcing levels (and the associated climate signal) are described by the new Representative Concentration Pathways. The second axis, socio-economic developments comprises elements that affect the capacity for mitigation and adaptation, as well as the exposure to climate impacts. The proposed scenarios derived from this framework are limited in number, allow for comparison across various mitigation and adaptation levels, address a range of vulnerability characteristics, provide information across climate forcing and vulnerability states and span a full century time scale. Assessments based on the proposed scenario framework would strengthen cooperation between integrated-assessment modelers, climate modelers and vulnerability, impact and adaptation researchers, and most importantly, facilitate the development of more consistent and comparable research within and across these research communities.  相似文献   

6.
The vulnerability of beach tourism to climate change—an index approach   总被引:2,自引:0,他引:2  
The attractiveness of a region for touristic activities depends strongly on the local weather and climate. This paper analyses the vulnerability of the beach tourism sector towards climate change by means of an index approach on a country level. A vulnerability framework for the tourism sector is developed and on its basis, indicators are defined for exposure, sensitivity and adaptive capacity. A transparent index approach, including a robustness analysis with multiple transformation methods and weighting sets, yields an assessment of the overall relative vulnerability of the beach tourism sector in 51 countries. Aggregate results on an annual level are presented as a starting point for a more detailed comparison of countries based on the individual indicators. The important limitations regarding the availability of accurate indicators as well as the concept of vulnerability itself are discussed. Despite these limitations, the present study contributes to integrating the numerous direct as well as indirect effects climate change may have on beach tourism.  相似文献   

7.
Summary Measuring turbulent fluxes with the eddy covariance method has become a widely accepted and powerful tool for the determination of long term data sets for the exchange of momentum, sensible and latent heat, and trace gases such as CO2 between the atmosphere and the underlying surface. Several flux networks developed continuous measurements above complex terrain, e.g. AmeriFlux and EUROFLUX, with a strong focus on the net exchange of CO2 between the atmosphere and the underlying surface. Under many conditions basic assumptions for the eddy covariance method in its simplified form, such as stationarity of the flow, homogeneity of the surface and fully developed turbulence of the flow field, are not fulfilled. To deal with non-ideal conditions which are common at many FLUXNET sites, quality tests have been developed to check if these basic theoretical assumptions are valid.In the framework of the CARBOEUROFLUX project, we combined quality tests described by Foken and Wichura (1996) with the analytical footprint model of Schmid (1997). The aim was to identify suitable wind sectors and meteorological conditions for flux measurements. These tools were used on data of 18 participating sites. Quality tests were applied on the fluxes of momentum, sensible and latent heat, and on the CO2-flux, respectively. The influence of the topography on the vertical wind component was also checked. At many sites the land use around the flux towers is not homogeneous or the fetch may not be large enough. So the relative contribution of the land use type intended to be measured was also investigated. Thus the developed tool allows comparative investigations of the measured turbulent fluxes at different sites if using the same technique and algorithms for the determination of the fluxes as well as analyses of potential problems caused by influences of the surrounding land use patterns.  相似文献   

8.
The term ‘vulnerability’ is used in many different ways by various scholarly communities. The resulting disagreement about the appropriate definition of vulnerability is a frequent cause for misunderstanding in interdisciplinary research on climate change and a challenge for attempts to develop formal models of vulnerability. Earlier attempts at reconciling the various conceptualizations of vulnerability were, at best, partly successful. This paper presents a generally applicable conceptual framework of vulnerability that combines a nomenclature of vulnerable situations and a terminology of vulnerability concepts based on the distinction of four fundamental groups of vulnerability factors. This conceptual framework is applied to characterize the vulnerability concepts employed by the main schools of vulnerability research and to review earlier attempts at classifying vulnerability concepts. None of these one-dimensional classification schemes reflects the diversity of vulnerability concepts identified in this review. The wide range of policy responses available to address the risks from global climate change suggests that climate impact, vulnerability, and adaptation assessments will continue to apply a variety of vulnerability concepts. The framework presented here provides the much-needed conceptual clarity and facilitates bridging the various approaches to researching vulnerability to climate change.  相似文献   

9.
To respond to climate impact, poor agricultural households in less developed regions rely on different types of assets that define their overall adaptive capacity (AC). However not all assets build capacity equally. In this study we argue that building AC requires a combination of interventions that address not only climate-related risks (specific capacity) but also the structural deficits (e.g., lack of income, education, health, political power) (generic capacity) that shape vulnerability. Focusing on rainfed agriculture in NE Brazil, we investigate how households leverage and combine generic and specific capacities to reduce vulnerability. Particularly we explore: 1) the relative importance of different kinds of capacity in shaping vulnerability on these households and 2) how the level of generic capacities (particularly as a result of Brazil’s anti-poverty program Bolsa Família) influences the adoption of specific ones. We find that both kinds of capacity matter, as relatively higher levels of generic capacity (in terms of income in general, and climate-neutral income specifically) are associated with higher levels of specific capacity (irrigation). In addition we find that while Bolsa Família has been positive in increasing income, it has not been sufficient to manage the risk of food insecurity during drought events, suggesting a 'poverty trap' in which families are constantly coping with drought but failing to overcome the conditions that make them vulnerable. Our findings indicate that in order to decrease climate vulnerability of poor agricultural households, development interventions, such as anti-poverty programs, have to go beyond cash transfer and should incorporate risk management policies that enhance synergies between generic and specific capacities.  相似文献   

10.
We argue that globalization is a central feature of coupled human–environment systems or, as we call them, socio-ecological systems (SESs). In this article, we focus on the effects of globalization on the resilience, vulnerability, and adaptability of these systems. We begin with a brief discussion of key terms, arguing that socio-economic resilience regularly substitutes for biophysical resilience in SESs with consequences that are often unforeseen. A discussion of several mega-trends (e.g. the rise of mega-cities, the demand for hydrocarbons, the revolution in information technologies) underpins our argument. We then proceed to identify key analytical dimensions of globalization, including rising connectedness, increased speed, spatial stretching, and declining diversity. We show how each of these phenomena can cut both ways in terms of impacts on the resilience and vulnerability of SESs. A particularly important insight flowing from this analysis centers on the reversal of the usual conditions in which large-scale things are slow and durable while small-scale things are fast and ephemeral. The fact that SESs are reflexive can lead either to initiatives aimed at avoiding or mitigating the dangers of globalization or to positive feedback processes that intensify the impacts of globalization. In the concluding section, we argue for sustained empirical research regarding these concerns and make suggestions about ways to enhance the incentives for individual researchers to work on these matters.  相似文献   

11.
The importance of ecological management for reducing the vulnerability of biodiversity to climate change is increasingly recognized, yet frameworks to facilitate a structured approach to climate adaptation management are lacking. We developed a conceptual framework that can guide identification of climate change impacts and adaptive management options in a given region or biome. The framework focuses on potential points of early climate change impact, and organizes these along two main axes. First, it recognizes that climate change can act at a range of ecological scales. Secondly, it emphasizes that outcomes are dependent on two potentially interacting and countervailing forces: (1) changes to environmental parameters and ecological processes brought about by climate change, and (2) responses of component systems as determined by attributes of resistance and resilience. Through this structure, the framework draws together a broad range of ecological concepts, with a novel emphasis on attributes of resistance and resilience that can temper the response of species, ecosystems and landscapes to climate change. We applied the framework to the world’s largest remaining Mediterranean-climate woodland, the ‘Great Western Woodlands’ of south-western Australia. In this relatively intact region, maintaining inherent resistance and resilience by preventing anthropogenic degradation is of highest priority and lowest risk. Limited, higher risk options such as fire management, protection of refugia and translocation of adaptive genes may be justifiable under more extreme change, hence our capacity to predict the extent of change strongly impinges on such management decisions. These conclusions may contrast with similar analyses in degraded landscapes, where natural integrity is already compromised, and existing investment in restoration may facilitate experimentation with higher risk?options.  相似文献   

12.
Using analyses of data from extant direct numerical simulations and large-eddy simulations of boundary-layer and channel flows over and within urban-type canopies, sectional drag forces, Reynolds and dispersive shear stresses are examined for a range of roughness densities. Using the spatially-averaged mean velocity profiles these quantities allow deduction of the canopy mixing length and sectional drag coefficient. It is shown that the common assumptions about the behaviour of these quantities, needed to produce an analytical model for the canopy velocity profile, are usually invalid, in contrast to what is found in typical vegetative (e.g. forest) canopies. The consequence is that an exponential shape of the spatially-averaged mean velocity profile within the canopy cannot normally be expected, as indeed the data demonstrate. Nonetheless, recent canopy models that allow prediction of the roughness length appropriate for the inertial layer’s logarithmic profile above the canopy do not seem to depend crucially on their (invalid) assumption of an exponential profile within the canopy.  相似文献   

13.
The element phosphorus underpins the viability of global and national food systems, by ensuring soil fertility, maximising crop yields, supporting farmer livelihoods and ultimately nutritional security of the global population. The implications of global phosphorus scarcity therefore have serious potential consequences for future food security, yet these implications have not been be comprehensively or sufficiently assessed at the global or national scales. This paper offers a new integrated framework for assessing the vulnerability of national food systems to global phosphorus scarcity—the Phosphorus Vulnerability Assessment framework. Drawing on developments in assessing climate and water vulnerability, the framework identifies and integrates 26 phosphorus-related biophysical, technical, geopolitical, socio-economic and institutional factors that can lead to food system vulnerability. The theoretical framework allows analysis of context-specific food system by examining impact due to exposure, sensitivity and adaptive capacity. The framework will also ultimately provide guidance for food and agriculture policy-makers, phosphate producers and phosphorus end-users (primarily farmers and consumers) to take action to reduce their vulnerability to this new global challenge.  相似文献   

14.
This paper builds on existing theory and proposes a framework to identify vulnerability to climate change in food systems by examining historic cases where common environmental problems caused famine. Cases presented are (1) Ireland’s Potato Famine, (2) El Niño induced famines during the Colonial period, and (3) Ethiopia between 1965 and 1997. Three factors stand out as common in each. Prior to each famine: (1) there were very few ways that people could obtain a living in the worst affected regions; (2) livelihoods in famine stricken communities came to depend on highly specialized agro-ecosystems that were sensitive to environmental change; (3) institutions failed to provide adequate safety nets to protect livelihoods from failure. This analysis suggests that vulnerability to climate change in food systems can be assessed by looking at agro-ecosystems, livelihoods and institutions. Local conditions, however, mean that ways of measuring these three factors will vary from place to place. As a result, direct comparisons are difficult. By conceptualizing these three variables as the axes of a three dimensional “vulnerability” space, it is possible to compare regions and look at trends over time by studying the paths through this “space” as traced by changes at the agro-ecosystem, livelihood, and institutional scale.  相似文献   

15.
Research on urban vulnerability has grown considerably during recent years, yet consists primarily of case studies based on conflicting theories and paradigms. Assessing urban vulnerability is also generally considered to be context-dependent. We argue, however, that it is possible to identify some common patterns of vulnerability across urban centers and research paradigms and these commonalities hold potential for the development of a common set of tools to enhance response capacity within multiple contexts. To test this idea we conduct an analysis of 54 papers on urban vulnerability to temperature-related hazards, covering 222 urban areas in all regions of the world. The originality of this effort is in the combination of a standard metaanalysis with a meta-knowledge approach that allows us not only to integrate and summarize results across many studies, but also to identify trends in the literature and examine differences in methodology, theoretical frameworks and causation narratives and thereby to compare “apples to oranges.” We find that the vast majority of papers examining urban vulnerability to temperature-related hazards come from an urban vulnerability as impact approach, and cities from middle and low income countries are understudied. One of the challenges facing scholarship on urban vulnerability is to supplement the emphasis on disciplinary boxes (e.g., temperature–mortality relationships) with an interdisciplinary and integrated approach to adaptive capacity and structural drivers of differences in vulnerability.  相似文献   

16.
17.
在研究区域雷电灾害易损性区划中,大多采用层次分析等方法来确定指标权重值,然而层次分析法在确定指标权重值时,人为主观因素较大,必然会给所建立的综合评估模型带来较大的误差.因此,利用主成分分析法,建立了雷电灾害易损性区划综合评价模型,从而很好地克服了层次分析等方法所带来的缺点,使得模型结果更接近于实际水平.利用海南省雷击大地密度、雷电灾害发生的频数、经济损失模数、生命易损模数以及人员伤亡频数等5个指标数据,采用所建立的雷电灾害易损性区划综合评价模型,对海南省雷电灾害易损性进行了实例分析.  相似文献   

18.
Climate variability has been evident on the Mongolian plateau in recent decades. Livelihood adaptation to climate variability is important for local sustainable development. This paper applies an analytical framework focused on adaptation, institutions, and livelihoods to study climate adaptation in the Mongolian grasslands. A household survey was designed and implemented in each of three broad vegetation types in Mongolia and Inner Mongolia. The analytical results show that livelihood adaptation strategies of herders vary greatly across the border between Mongolia and Inner Mongolia, China. Local institutions played important roles in shaping and facilitating livelihood adaptation strategies of herders. Mobility and communal pooling were the two key categories of adaptation strategies in Mongolia, and they were shaped and facilitated by local communal institutions. Storage, livelihood diversification, and market exchange were the three key categories of adaptation strategies in Inner Mongolia, and they were mainly shaped and facilitated by local government and market institutions. Local institutions enhanced but also at times undermined adaptive capacity of herder communities in the two countries, but in different ways. Sedentary grazing has increased livelihood vulnerability of herders to climate variability and change. With grazing sedentarization, the purchase and storage of forage has become an important strategy of herders to adapt to the highly variable climate. The multilevel statistical models of forage purchasing behaviors show that the strategies of livestock management, household financial capital, environmental (i.e., precipitation and vegetation growth) variability, and the status of pasture degradation were the major determinants of this adaptation strategy.  相似文献   

19.
Vertical heat fluxes induced by mesoscale thermally driven circulations maycontribute significantly to the subgrid-scale fluxes in large-scale models (e.g.,general circulation models). However, they are not considered in these modelsyet. To gain insight into the importance and possible parameterisation of themesoscale flux associated with slope winds, an analytical (conceptual) modelis developed to describe the relationship between the mesoscale heat flux andatmospheric and land-surface characteristics. The analytical model allows usto evaluate the mesoscale flux induced by slope winds from only a few profilemeasurements within a domain. To validate the analytical model the resultingheat flux profiles are compared to profiles of highly resolved wind and temperaturefields obtained by simulations with a mesoscale numerical model.With no or moderate synoptic wind the mesoscale heat flux generated by the slopewind circulation may be as large as, or even larger than, the turbulent fluxes at thesame height. At altitudes lower than the crest of the hills the mesoscale flux is alwayspositive (upward). Generally it causes cooling within the boundary layer and heatingabove. Despite the simplifications made to derive the analytical model, it reproducesthe profiles of the mesoscale flux quite well. According to the analytical model, themesoscale heat flux is governed by the temperature deviation at the slope surface, thedepth of the slope-wind layer, the large-scale lapse rate, and the wavelength of thetopographical features.  相似文献   

20.
Large-eddy simulation (LES), coupled with a wind-turbine model, is used to investigate the characteristics of a wind-turbine wake in a neutral turbulent boundary-layer flow. The tuning-free Lagrangian scale-dependent dynamic subgrid-scale (SGS) model is used for the parametrisation of the SGS stresses. The turbine-induced forces (e.g., thrust, lift and drag) are parametrised using two models: (a) the ‘standard’ actuator-disk model (ADM-NR), which calculates only the thrust force and distributes it uniformly over the rotor area; and (b) the actuator-disk model with rotation (ADM-R), which uses the blade-element theory to calculate the lift and drag forces (that produce both thrust and rotation), and distribute them over the rotor disk based on the local blade and flow characteristics. Simulation results are compared to high-resolution measurements collected with hot-wire anemometry in the wake of a miniature wind turbine at the St. Anthony Falls Laboratory atmospheric boundary-layer wind tunnel. In general, the characteristics of the wakes simulated with the proposed LES framework are in good agreement with the measurements in the far-wake region. The ADM-R yields improved predictions compared with the ADM-NR in the near-wake region, where including turbine-induced flow rotation and accounting for the non-uniformity of the turbine-induced forces appear to be important. Our results also show that the Lagrangian scale-dependent dynamic SGS model is able to account, without any tuning, for the effects of local shear and flow anisotropy on the distribution of the SGS model coefficient.  相似文献   

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