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1.
In this paper we develop economic measures of vulnerability to climate change with and without adaptation in agricultural production systems. We implement these measures using coupled, site-specific ecosystem and economic simulation models. This modeling approach has two key features needed to study the response of agricultural production systems to climate change: it represents adaptation as an endogenous, non-marginal economic response to climate change; and it provides the capability to represent the spatial variability in bio-physical and economic conditions that interact with adaptive responses. We apply this approach to the dryland grain production systems of the Northern Plains region of the United States. The results support the hypothesis that the most adverse impacts on net returns distributions tend to occur in the areas with the poorest resource endowments and when mitigating effects of CO2 fertilization and adaptation are absent. We find that relative and absolute measures of vulnerability depend on complex interactions between climate change, CO2 level, adaptation, and economic conditions such as relativeoutput prices. The relationship between relative vulnerability and resource endowments varies with assumptions about climate change, adaptation, and economic conditions. Vulnerability measured with respect to an absolute threshold is inversely related to resource endowments in all cases investigated.  相似文献   

2.
利用FSU(Florida State University)风应力逐月资料,运用POP方法,分析了热带太平洋地区风应力异常场结构与ENSO的联系。结果显示:纬向风应力有35、47和57月周期的传播型振荡;经向风应力有28和38月周期的传播型振荡。得到纬向、经向风应力传播型与ENSO振荡的耦合关系。同时指出,对El Nino/La Nina这样的大尺度海气相互作用现象的时空演变,应注重多种振荡混合的作用,而不应只分析单一模态的作用。风应力异常的局地振荡对El Nino/La Nina的影响也不应忽视。  相似文献   

3.
Coral reefs support the livelihood of millions of people especially those engaged in marine fisheries activities. Coral reefs are highly vulnerable to climate change induced stresses that have led to substantial coral mortality over large spatial scales. Such climate change impacts have the potential to lead to declines in marine fish production and compromise the livelihoods of fisheries dependent communities. Yet few studies have examined social vulnerability in the context of changes specific to coral reef ecosystems. In this paper, we examine three dimensions of vulnerability (exposure, sensitivity, and adaptive capacity) of 29 coastal communities across five western Indian Ocean countries to the impacts of coral bleaching on fishery returns. A key contribution is the development of a novel, network-based approach to examining sensitivity to changes in the fishery that incorporates linkages between fishery and non-fishery occupations. We find that key sources of vulnerability differ considerably within and between the five countries. Our approach allows the visualization of how these dimensions of vulnerability differ from site to site, providing important insights into the types of nuanced policy interventions that may help to reduce vulnerability at a specific location. To complement this, we develop framework of policy actions thought to reduce different aspects of vulnerability at varying spatial and temporal scales. Although our results are specific to reef fisheries impacts from coral bleaching, this approach provides a framework for other types of threats and different social-ecological systems more broadly.  相似文献   

4.
金有杰  曾燕  邱新法  李东 《气象科学》2014,34(5):522-529
基于统计年鉴资料和土地利用数据,分别建立人口、GDP空间化模型,模拟南京市浦口区人口和GDP的空间分布。并结合暴雨洪涝历史灾情数据,探索区县级行政区域暴雨洪涝灾害承灾体脆弱性风险评估技术方法,最终获得100 m×100 m格网的浦口区暴雨洪涝灾害承灾体脆弱性空间分布图。研究结果表明:(1)人口、GDP的空间化模拟结果,既与各镇街统计数据保持一致,又反映了各镇街内部的人口、GDP分布的空间变化,可以为承灾体脆弱性评估提供精细化、可靠的数据源。(2)浦口区暴雨洪涝灾害承灾体脆弱性高风险区,分布在东北部经济较为发达的城镇街道而老山山脉和沿江内陆滩涂地区脆弱性风险较低。  相似文献   

5.
Public perceptions of rainfall change in India   总被引:1,自引:1,他引:0  
People’s perceptions of changes in local weather patterns are an important precursor to proactive adaptation to climate change. In this paper, we consider public perceptions of changes in average rainfall in India, analyzing the relationship between perceptions and the instrumental record. Using data from a national sample survey, we find that local instrumental records of precipitation are a strong predictor of perceived declines in rainfall. Perceptions of decreasing rainfall were also associated with perceptions of changes in extreme weather events, such as decreasing frequency of floods and severe storms, increasing frequency of droughts, and decreasing predictability of the monsoon. Higher social vulnerability—including low perceived adaptive capacity and greater food and livelihood dependence on local weather—was also associated with perceptions of decreasing rainfall. While both urban and rural respondents were likely to perceive local changes in precipitation, we show that rural respondents in general were more sensitive to actual changes in precipitation. Individual perceptions of changes in local climate may play an important role in shaping vulnerability to global climate change, adaptive behavior, and support for adaptation and mitigation policies. Awareness of local climate change is therefore particularly important in regions where much of the population is highly exposed and sensitive to the impacts of climate change.  相似文献   

6.
Despite improvements in understanding biophysical response to climate change, a better understanding of how such changes will affect societies is still needed. We evaluated effects of climate change on the coupled human-environmental system of the McKenzie River watershed in the Oregon Cascades in order to assess its vulnerability. Published empirical and modeling results indicate that climate change will alter both the timing and quantity of streamflow, but understanding how these changes will impact different water users is essential to facilitate adaptation to changing conditions. In order to better understand the vulnerability of four water use sectors to changing streamflow, we conducted a series of semi-structured interviews with representatives of each sector, in which we presented projected changes in streamflow and asked respondents to assess how changing water availability would impact their activities. In the McKenzie River watershed, there are distinct spatial and temporal patterns associated with sensitivity of water resources to climate change. This research illustrates that the implications of changing streamflow vary substantially among different water users, with vulnerabilities being determined in part by the spatial scale and timing of water use and the flexibility of those uses in time and space. Furthermore, institutions within some sectors were found to be better positioned to effectively respond to changes in water resources associated with climate change, while others have substantial barriers to the flexibility needed to manage for new conditions. A clearer understanding of these opportunities and constraints across water use sectors can provide a basis for improving response capacity and potentially reducing vulnerability to changing water resources in the region.  相似文献   

7.
This article suggests a framework for incorporating and communicating local perceptions of hurricane risk into policymaking through a case study conducted at El Zapotito commune in the State of Veracruz, Mexico. The authors constructed a geographical information system (GIS)-based model to quantify and spatially assess specific household-level vulnerabilities from information generated through interviews. This research developed a household vulnerability index applied to a participatory GIS to map vulnerability to hurricane hazard. The results indicate that infrastructural weaknesses are the most important factor contributing to vulnerability, explaining on their own 72.2% of the variation in the vulnerability patterns. These findings are corroborated by a vulnerability and capacity assessment (VCA), which shows that the community lacks strategies to cope with unsafe housing. It is suggested that linking community participation with modern techniques to analyse risk can empower communities and mobilise their capacities to address very specific vulnerabilities.  相似文献   

8.
Ethiopia??s agriculture is predominantly rainfed and hence any irregularity in weather conditions has adverse welfare implications. Using panel data, this paper analyzes the effect of rainfall shocks on Ethiopian rural households?? food security and vulnerability over time while controlling for a range of other factors. To this end, we generate a time-variant household food security index which is developed by principal components analysis. Based on this index, households are classified into relative food security groups and their socioeconomic differences are assessed. The exploratory results show that compared to the less secured households, the more secured ones have male and literate household heads, tend to have a greater number of economically active household members, own more livestock, experience better rainfall outcome, and participate in local savings groups. Using the food security index as the dependent variable, we use a fixed effects instrumental variable regression model to identify determinants of households?? food security over time and find that rainfall variability is an important factor. Moreover, household size, participation in local savings groups, and livestock ownership positively affect food security. Results from multinomial logistic regression model complement the fixed effects instrumental variable regression results by showing that the level and variability of rainfall are important determinants of persistent food insecurity and vulnerability. The results highlight the need for efficient risk reduction and mitigation programs to improve risk exposure and coping ability of rural households. Careful promotion of investment in infrastructure to support irrigation and water resources development is one aspect worth considering.  相似文献   

9.
中国东部夏季降水与东亚垂直环流结构及其预测试验   总被引:2,自引:1,他引:1  
韩雪  魏凤英 《大气科学》2010,34(3):533-547
本文在分析中国东部夏季降水的时空分布特征基础上, 从东亚高、中、低层大尺度环流异常着手, 选取对中国东部夏季降水异常有显著影响的大气环流预报因子, 分别应用逐步回归和最优子集回归法两种统计降尺度方法, 以动力气候模式CAM3.1预报输出的大气环流预报因子为基础, 以中国东部夏季降水的典型空间分布型为预报对象, 建立动力与统计相结合的中国东部夏季降水预测模型, 并对1981~2000年的中国东部夏季降水进行回报试验。结果表明: 中国东部夏季降水具有4类典型的空间分布型式, 且具有显著的准2年和年代际尺度振荡周期; 东亚高、中、低层大气环流异常的特定配置, 对东部夏季降水的空间分布型有显著影响; 使用两种降尺度方案建立的动力与统计相结合的预测模型对中国东部夏季降水异常具有一定的预报技巧, 可以在一定程度上提高动力模式对中国东部夏季降水的预报效果。  相似文献   

10.
The public health implications of a warming urban environment mean that appropriate action by planners, designers and health workers will be necessary to minimise risk under future climate scenarios. Data at an appropriate spatial scale are required by user groups in order to identify key areas of vulnerability. Thermal mapping of a UK urban conurbation was carried out during the summers of 2007 and 2008 with the aim of providing high spatial resolution temperature data. The air temperature results showed an average daytime (night time) urban?Crural thermal contrast of 3°C (5°C) on summer days (nights) with ideal urban heat island (UHI) conditions. The intensity of the daytime surface temperature heat island was found to exceed 10°C. The measured data were used to derive an empirical model of spatial temperature patterns based upon characteristics of land use, distance from urban centre and building geometry. This model can be used to provide sub-kilometre resolution temperature data which are required by decision makers and can provide a mechanism for downscaling climate model output.  相似文献   

11.
冬季积雪的异常分布型及其与冬、夏大气环流的耦合关系   总被引:4,自引:0,他引:4  
采用 ECMWF1 979~ 1 993年 2 .5°× 2 .5°的网格点积雪深度资料 ,研究了较为细致的积雪异常的空间分布特征 ,揭示了欧亚大陆冬季积雪的异常空间分布型 ;并采用 SVD方法研究了冬季积雪的异常分布型与冬、夏大气环流的耦合关系。结果表明 :欧亚大陆冬季积雪深度存在典型的异常空间分布型 ;积雪的异常分布型与冬、夏大气环流之间均存在一定的耦合关系。冬季积雪的异常分布型与大气 EU遥相关型存在明显的同时性相互作用 ,大气 EU遥相关型有利于冬季积雪异常分布型的出现和维持 ,而积雪异常分布型对大气 EU遥相关型的发生起一定的作用 ,进而对冬季风活动产生影响。冬季积雪的这种异常分布型与夏季大气环流 ,尤其是东亚地区的夏季大气环流 ,也存在一定的联系。积雪异常分布型可以通过影响副热带高压的南北进退 ,对东亚季风及中国夏季雨带产生影响。  相似文献   

12.
Behavioural models that allow simple representation of the complexity of human–environment links are important in vulnerability assessment because they allow the analysis of human adaptive processes in a changing environment. This paper applies an agent-based framework that considers the behavioural model of farmers in three villages in a municipality in the Philippines. Agent-based modelling is a useful policy tool for simulating the effects of different adaptation options on reducing vulnerability because it allows representation of not only the dynamic changes in climate and market but also the dynamic adaptive process of different groups of communities to the impacts of these changes. Model simulations of adaptation options under various global change scenarios showed that production support would significantly reduce future vulnerability only if complemented with appropriate market support. It is thus important for policy to provide a complementary bundle of adaptation measures. Lack of money and information are the most important reasons for not applying available technical adaptation measures, which currently hinder reduction of vulnerability in selected villages in the municipality. Social networks, which play an important role in adapting to environmental changes, are limited to relatives and neighbours, who are important sources of informal credit.  相似文献   

13.
There is a growing research interest on the transdisciplinary measurement of vulnerability to climatic hazards from the perspective of integrated river basin management. However, the incorporation of stakeholders’ participation, local knowledge and locally spatial characteristics into the process of such vulnerability assessment is one of the challenges faced by decision-makers, especially in developing countries. This article proposes a novel methodology for assessing and communicating vulnerability to policymaking at the river basin level through a case study of Tachia River basin in Taiwan. The authors used a multicriteria decision analysis to develop an integrated vulnerability index applied to a participatory geographic information system (GIS) to map vulnerability to climatic hazards. Using a GIS-based spatial statistics technique and multivariate analysis, we test the degree to which vulnerabilities are spatially autocorrelated throughout the river basin, explain why clustering of vulnerable areas occurs in specific locations, and why some regions are particularly vulnerable. Results demonstrate that vulnerable areas are spatially correlated across the river basin. Moreover, exposure, biophysical sensitivity, land uses and adaptive capacity are key factors contributing to the formation of localized ‘hot spots’ of similarly and particularly vulnerable areas. Finally, we discuss how the findings provide direction for more effective approaches to river basin planning and management.  相似文献   

14.
This empirical and interdisciplinary study investigates the contribution of deeply enrooted social-political factors to the accumulation of exposure and vulnerability and amplification of cascading impacts of disasters, with implications on the creation and reinforcement of path dependency maintaining social-ecological systems on a maladaptive trajectory. Applying the Trajectory of Exposure and Vulnerability approach to Saint-Martin (Caribbean), we more specifically highlight how the causal chain linking historical geopolitical and political-institutional drivers to legal, economic, demographic, sociocultural, planning-related and environmental drivers, created the accumulation of exposure and vulnerability over time and contributed to the propagation and amplification of the impacts of tropical cyclones Irma and José in 2017. We find that historical social-political dynamics involving unsustainable development and settlement patterns, the weakness of local institutions, population mistrust in public authorities, high social inequalities and environmental degradation maintained Saint-Martin on a maladaptive trajectory through powerful reinforcing mechanisms operating both between and during cyclonic events. This study demonstrates that long-term interdisciplinary approaches are required for a better understanding of path dependency and the identification of levers to break it in risk-prone contexts. In Saint-Martin, breaking path dependency requires the alignment of local institutional capacities with national risk reduction policies, the promotion of social justice and involvement of local communities in decision making. This study therefore confirms the relevance of backward-looking approaches to support forward-looking climate adaptation.  相似文献   

15.
The need to mainstream adaptation to climate change into development planning and ongoing sectoral decision-making is increasingly recognised, and several bilateral and multilateral development agencies are starting to take an interest. Over the past years at least six development agencies have screened their project portfolios, generally with two goals in mind: (1) to ascertain the extent to which existing development projects already consider climate risks or address vulnerability to climate variability and change, and (2) to identify opportunities for incorporating climate change explicitly into future projects. As each portfolio screening was conducted independently, the broader lessons emerging from the screenings have not been systematically analysed. In this paper we assess the screening activities to date, focusing on both the results and the methods applied. Based on this assessment we identify opportunities for development agencies to expand their current focus on the links between climate and development. Most agencies already consider climate change as a real but uncertain threat to future development, but they have given less thought to how different development patterns might affect vulnerability to climate change. The screenings undertaken have shown the need to take a comprehensive approach to adaptation and its integration into development planning and sectoral decision-making, and a number of policy initiatives have been taken to promote such integration. We provide some initial guidance as to how portfolio screening can be carried out in a way that would allow agencies to assess systematically the relevance of climate change to their ongoing and planned development projects.  相似文献   

16.
Yohe and Tol (2002. Global Environmental Change 12, 25–40) built an indexing method for vulnerability based on the hypothesis that the adaptive capacity for any system facing a vector of external stresses could be explained by the weakest of its underlying determinants—the so-called “weakest link” hypothesis. Their structure noted eight determinants, but the approach could handle any number. They quoted analogies in support of the hypothesis, but loose inference is hardly sufficient to confirm such a claim. We respond to this omission by offering an empirical investigation of its validity. We estimate a structural form designed to accommodate the full range of possible interactions across sets of underlying determinants. The perfect complement case of the pure “weakest-link” formulation lies on one extreme, and the perfect substitute case where each determinant can compensate for all others at constant rates is the other limiting case. For vulnerability to natural disasters, infant mortality and drinking water treatment, we find qualified support for a modified weakest link hypothesis: the weakest indicator plays an important role because other factors can compensate (with increasing difficulty). For life expectancy, sanitation and nutrition, we find a relationship that is close to linear—the perfect substitute case where the various determinants of adaptive capacity can compensate for each other with relative and persistent ease. Moreover, since the factors from which systems derive their adaptive capacities are different for different risks, we have identified another source of diversity in the assessment of vulnerability.  相似文献   

17.
ABSTRACT

It has been frequently observed that there are surface cold patches (SCPs) in the Yellow Sea in summer. Although previous studies based on monthly mean temperature distribution found that these SCPs are a result of tidal mixing and tide-induced upwelling, tidal mixing and upwelling alone cannot explain all the occurrences. In our study we found that the three typical patches, namely, the Shandong SCP, the Subei SCP, and the Mokpo SCP, have different temporal patterns over a spring–neap tidal cycle; hence, they have different generating mechanisms. Based on a multiple-year simulation, the latter two show conspicuous spring–neap variations. The highest temperature occurs during the neap tide phase (about two days after a quarter moon). Because of weak upwelling and mixing, strong stratification is established and the SCPs are suppressed or even disappear. The opposite holds for the spring tide phase (about two days after a new or full moon). This is quite different from the Shandong SCP, which does not display a distinct difference between spring and neap tides. Buoy observations and composite analyses with data from the Moderate Resolution Imaging Spectroradiometer (MODIS) further support this conclusion.  相似文献   

18.
Crop growth models, used in climate change impact assessments to project production on a local scale, can obtain the daily weather information to drive them from models of the Earth's climate. General Circulation Models (GCMs), often used for this purpose, provide weather information for the entire globe but often cannot depict details of regional climates especially where complex topography plays an important role in weather patterns. The U.S. Pacific Northwest is an important wheat growing region where climate patterns are difficult to resolve with a coarse scale GCM. Here, we use the PNNL Regional Climate Model (RCM) which uses a sub-grid parameterization to resolve the complex topography and simulate meteorology to drive the Erosion Productivity Impact Calculator (EPIC) crop model. The climate scenarios were extracted from the PNNL-RCM baseline and 2 × CO2 simulationsfor each of sixteen 90 km2 grid cells of the RCM, with differentiation byelevation and without correction for climate biases. The dominant agricultural soil type and farm management practices were established for each grid cell. Using these climate and management data in EPIC, we simulated winter wheat production in eastern Washington for current climate conditions (baseline) and a 2 × CO2 `greenhouse' scenario of climate change.Dryland wheat yields for the baseline climate averaged 4.52 Mg ha–1 across the study region. Yields were zero at high elevations where temperatures were too low to allow the crops to mature. The highest yields (7.32 Mgha–1) occurred at intermediate elevations with sufficientprecipitation and mild temperatures. Mean yield of dryland winter wheat increased to 5.45 Mg ha–1 for the 2 × CO2 climate, which wasmarkedly warmer and wetter. Simulated yields of irrigated wheat were generally higher than dryland yields and followed the same pattern but were, of course, less sensitive to increases in precipitation. Increases in dryland and irrigated wheat yields were due, principally, to decreases in the frequency of temperature and water stress. This study shows that the elevation of a farm is a more important determinant of yield than farm location in eastern Washington and that climate changes would affect wheat yields at all farms in the study.  相似文献   

19.
Africa is widely held to be highly vulnerable to future climate change and Ethiopia is often cited as one of the most extreme examples. With this in mind we seek to identify entry points to integrate short- to medium-term climate risk reduction within development activities in Africa, drawing from experiences in Ethiopia. To achieve this we employ a range of data and methods. We examine the changing nature of climate risks using analysis of recent climate variability, future climate scenarios and their secondary impacts. We assess the effects of climate variability on agricultural production and national GDP. Entry points and knowledge gaps in relation to mainstreaming climate risks in Ethiopia are identified using the Government's plan for poverty reduction. We end with a case study incorporating climate risks through drought insurance within the current social protection programme in Ethiopia, which provides support to 8.3 million people.Rainfall behaviour in Ethiopia shows no marked emergent changes and future climate projections show continued warming but very mixed patterns of rainfall change. Economic analysis highlights sensitivities within the economy to large-scale drought, however, while the effects are clear in major drought years in other years the relationship is weak. For social protection fairly small positive and negative effects on the number of recipients and frequency of cash payments during drought occur under the extreme range of climate model rainfall projections (2020s).Our analysis highlights several important challenges and opportunities for addressing climate risks. Challenges primarily relate to the large uncertainties in climate projections for parts of Africa, a weak evidence base of complex, often non-deterministic, climate-society interactions and institutional issues. Opportunities relate to the potential for low-regrets measures to reduce vulnerability to current climate variability which can be integrated with relatively modest effort within a shift in Africa from a disaster-focused view of climate to a long-term perspective that emphasises livelihood security and vulnerability reduction.  相似文献   

20.
Understanding vulnerability to the impacts of global environmental change and identifying adaptation measures to cope with these impacts require localized investigations that can help find actual and exact answers to the questions about who and what are vulnerable, to what are they vulnerable, how vulnerable are they, what are the causes of their vulnerability, and what responses can lessen their vulnerability. People living in forests are highly dependent on forest goods and services, and are vulnerable to forest changes both socially and economically. In the Congo basin, climate change effects on forest ecosystems are predicted to amplify the existing pressure on food security urging expansion of current agricultural lands at the expense of forest, biodiversity loss and socioeconomic stresses. The paper aimed at exploring vulnerability and adaptation needs to climate change of local communities in the humid forest zone of Cameroon. Field work was conducted in two forest communities in Lekié and in Yokadouma in the Center and Eastern Regions of Cameroon respectively. The assessment was done using a series of approaches including a preparatory phase, fieldwork proper, and validation of the results. Results show that: (a) the adverse effects of climate conditions to which these communities are exposed are already being felt and exerting considerable stress on most of their livelihoods resources; (b) drought, changing seasons, erratic rain patterns, heavy rainfall and strong winds are among the main climate-related disturbances perceived by populations in the project sites; (c) important social, ecological and economic processes over the past decades seemed to have shaped current vulnerability in the sites; (d) Some coping and adaptive strategies used so far are outdated; and specific adaptation needs are identified and suggestions for facilitating their long-term implementations provided.  相似文献   

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