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1.
极端事件对人类系统的影响   总被引:1,自引:0,他引:1  
在IPCC特别报告《管理极端事件和灾害风险,推进气候变化适应》中,极端天气气候事件对人类系统的影响是最重要的影响评估内容之一,其评估结果为:极端影响可能缘于极端天气气候事件,但也可能并非极端事件的后果。暴露度和脆弱性是灾害风险的重要决定因素;极端和非极端天气气候事件的严重程度和影响在很大程度上取决于对这些事件的脆弱性和暴露度水平;人居模式、城市化和社会经济状况的变化已经影响观测到的脆弱性和暴露度的变化趋势;无论在发达国家还是发展中国家,沿海人居环境均暴露于极端事件,并受其影响,如小岛屿国家和亚洲大三角洲地区;脆弱人口还包括难民、国内流离失所的人和那些生活在边远地区的人;极端事件将极大地影响与气候联系密切的部门,如水、农业、食物安全、健康和旅游业。  相似文献   

2.
Most studies on the impact of climate change on regional water resources focus on long-term average flows or mean water availability, and they rarely take the effects of altered human water use into account. When analyzing extreme events such as floods and droughts, the assessments are typically confined to smaller areas and case studies. At the same time it is acknowledged that climate change may severely alter the risk of hydrological extremes over large regional scales, and that human water use will put additional pressure on future water resources. In an attempt to bridge these various aspects, this paper presents a first-time continental, integrated analysis of possible impacts of global change (here defined as climate and water use change) on future flood and drought frequencies for the selected study area of Europe. The global integrated water model WaterGAP is evaluated regarding its capability to simulate high and low-flow regimes and is then applied to calculate relative changes in flood and drought frequencies. The results indicate large ‘critical regions’ for which significant changes in flood or drought risks are expected under the proposed global change scenarios. The regions most prone to a rise in flood frequencies are northern to northeastern Europe, while southern and southeastern Europe show significant increases in drought frequencies. In the critical regions, events with an intensity of today's 100-year floods and droughts may recur every 10–50 years by the 2070s. Though interim and preliminary, and despite the inherent uncertainties in the presented approach, the results underpin the importance of developing mitigation and adaptation strategies for global change impacts on a continental scale.  相似文献   

3.
与IPCC第五次评估报告相比,第六次评估报告(AR6)有关农业的评估对象由作物生产系统延伸到粮食供应链系统,气候变化对作物生产不利影响的证据在加强。气候变化改变了作物适宜种植区,使中高纬度及温带地区作物种植界限向高纬度、高海拔地区推移。人为引起的气候变暖阻碍了作物产量的增长,地表O3浓度增加使作物产量降低,CH4排放加剧了这种不利影响。气候变化加剧作物病虫草害,极端气候事件高发加剧了粮食不安全,推升了国际粮食价格。适应措施有助于减缓气候变化不利影响,基于自然的适应方案在增强作物生产系统气候恢复力和保障粮食安全方面具有较高潜力。从保障国家粮食安全和重大战略需求出发,AR6报告对我国农业应对气候变化相关工作的启示如下:需要高度重视气候变化背景下作物种植适宜区转变与种植带北移的重要战略价值,合理规划农业生产布局;加强农业气象灾害和病虫害防治体系和能力建设,保障粮食生产稳定性;关注气候变化对国际作物生产和谷物贸易的影响,统筹国内、国际市场粮食资源,保障粮食安全;推进农业温室气体减排与作物生产高效协同,为实现国家减排目标做出贡献。  相似文献   

4.
Food production in China is a fundamental component of the national economy and driver of agricultural policy. Sustaining and increasing output to meet growing demand faces significant challenges including climate change, increasing population, agricultural land loss and competing demands for water. Recent warming in China is projected to accelerate by climate models with associated changes in precipitation and frequency of extreme events. How changes in cereal production and water availability due to climate change will interact with other socio-economic pressures is poorly understood. By linking crop and water simulation models and two scenarios of climate (derived from the Regional Climate Model PRECIS) and socio-economic change (downscaled from IPCC SRES A2 and B2) we demonstrate that by the 2040s the absolute effects of climate change are relatively modest. The interactive effects of other drivers are negative, leading to decreases in total production of ?18% (A2) and ?9% (B2). Outcomes are highly dependent on climate scenario, socio-economic development pathway and the effects of CO2 fertilization on crop yields which may almost totally offset the decreases in production. We find that water availability plays a significant limiting role on future cereal production, due to the combined effects of higher crop water requirements (due to climate change) and increasing demand for non-agricultural use of water (due to socio-economic development). Without adaptation, per capita cereal production falls in all cases, by up to 40% of the current baseline.By simulating the effects of three adaptation scenarios we show that for these future scenarios China is able to maintain per capita cereal production, given reasonable assumptions about policies on land and water management and progress in agricultural technology. Our results are optimistic because PRECIS simulates much wetter conditions than a multi-model average, the CO2 crop yield response function is highly uncertain and the effects of extreme events on crop growth and water availability are likely to be underestimated.  相似文献   

5.
Unusually severe or prolonged drought ranks among the most devastating and calamitous of all extreme climate events, contributing to wildfires, crop failure, livestock death, food shortages and famine. The response of human activities and the natural environment to such historical weather perturbations provides a guide to where the most critical sensitivities to future climate changes may lie (McCarthy et al., 2001, ‘Climatic change 2001: Impact adaptation, and vulnerability’, from 3rd Assesment Report of IPCC). The reconstruction of regional climatic histories and investigations of the impacts of – and social response to – extreme droughts in history are thus of crucial significance if we are to understand and anticipate the potential repercussions of future events (Wigley, 1985, Nature 316, 106–107; Grove and Conterio, 1995, Clim. Change 30, 223). Chihuahua, in the arid Northwest of Mexico, is one of the most seriously and frequently drought affected regions of the country (Garcia, 2000, available at www.sequia.edu.mx/proyectos/vulnera.html). Prolonged drought in the 1930s, 1950s and 1990s contributed to water scarcity, harvest failure, illness, livestock disease, abandonment and water conflict and served to highlight the particular vulnerability of agrarian society in this region to climatic variability (Sandoval, 2003, Ingeneria Hidraulica en Mexico 18(2), 133–155). Recent investigations using tree ring analysis have identified several phases of such prolonged drought over the last seven centuries. In this paper we use archival documents to investigate the impacts of such periods in late colonial Chihuahua and to explore how society in the region responded to and coped with them.  相似文献   

6.
During this century global warming will lead to changes in global weather and climate, affecting many aspects of our environment. Agriculture is the sector of the United States economy most likely to be directly impacted by climatic changes. We have examined potential changes in dryland agriculture (Part 3) and in water resources necessary for crop production (Part 4) in response to a set of climate change scenarios. In this paper we assess to what extent, under these same scenarios, water supplies will be sufficient to meet the irrigation requirement of major grain crops in the US. In addition, we assess the overall impacts of changes in water supply on national grain production. We apply the 12 climate change scenarios described in Part 1 to the water resources and crop growth simulation models described in Part 2 for the conterminous United States. Drawing on data from Parts 3 and 4 we calculate what the aggregate national production would be in those regions in which grain crops are currently produced by applying irrigation where needed and water supplies allow. The total amount of irrigation water applied to crops declines under all climate change scenarios employed in this study. Under certain of the scenarios and in particular regions, precipitation decreases so much that water supplies are too limited; in other regions precipitation becomes so plentiful that little value is derived from irrigation. Nationwide grain crop production is greater when irrigation is applied as needed. Under irrigation, less corn and soybeans are produced under most of the climate change scenarios than is produced under baseline climate conditions. Winter wheat production under irrigation responds significantly to elevated atmospheric carbon dioxide concentrations [CO2] and appears likely to increase under climate change.  相似文献   

7.
It is expected that a warmer climate would be beneficial for agriculture in high latitudes. However, this general tendency is not necessarily true for all northern countries, as a short growing period is not the only factor limiting agriculture. For Russia, our model shows that the remarkable increase in potential yield in central and northern-forested regions would not compensate for a sharp drop in yields due to increasing frequency of droughts in the currently most productive southern European regions. If this scenario is indeed realized, the majority of Russian regions will continue to rely on import of agricultural products from a few regions with the best soils, and a system of interregional grain trade will remain critical for food security. However, the basic rules of interregional food market have varied widely over the past century. We have attempted an analysis of the potential impact of these basic rules on regional food security by describing four basic historical market scenarios and applying these scenarios to our results for climate change impact on agriculture in the 2020s and 2070s. We show that the current system, if it continues, would bring the worst results. We also show that the traditionally effective planned adaptation measures would help little in future climate conditions if the current market system were still in place.  相似文献   

8.
Agriculture and forestry will be particularly sensitive to changes in mean climate and climate variability in the northern and southern regions of Europe. Agriculture may be positively affected by climate change in the northern areas through the introduction of new crop species and varieties, higher crop production and expansion of suitable areas for crop cultivation. The disadvantages may be determined by an increase in need for plant protection, risk of nutrient leaching and accelerated breakdown of soil organic matter. In the southern areas the benefits of the projected climate change will be limited, while the disadvantages will be predominant. The increased water use efficiency caused by increasing CO2 will compensate for some of the negative effects of increasing water limitation and extreme weather events, but lower harvestable yields, higher yield variability and reduction in suitable areas of traditional crops are expected for these areas. Forestry in the Mediterranean region may be mainly affected by increases in drought and forest fires. In northern Europe, the increased precipitation is expected to be large enough to compensate for the increased evapotranspiration. On the other hand, however, increased precipitation, cloudiness and rain days and the reduced duration of snow cover and soil frost may negatively affect forest work and timber logging determining lower profitability of forest production and a decrease in recreational possibilities. Adaptation management strategies should be introduced, as effective tools, to reduce the negative impacts of climate change on agricultural and forestry sectors.  相似文献   

9.
气候变化对中国农业生产的影响研究进展   总被引:54,自引:6,他引:48       下载免费PDF全文
气候变化已成为当今科学界、各国政府和社会公众普遍关注的环境问题之一,气候变化可能对生态系统和社会经济产生灾难性影响,农业是受气候变化影响最直接的脆弱行业。因此,气候变化对农业生产的影响研究一直是气候变化研究领域中的热点问题之一。该文系统介绍了有关全球气候变化对中国农业生产影响研究的现状与进展,包括气候变化对农业影响的研究方法、大气中温室气体浓度增加对农作物的影响试验、气候变化对农业气候资源的影响、气候变化对农作物生长发育和产量的影响、气候变化对农业种植制度和品种布局的影响、气候变化对农作物气候生产潜力和气候资源利用率的影响等,指出当前在研究气候变化对农业影响评估中存在的问题,提出了今后应加强对气候变化情景和预测模式不确定性的研究、气候变化对农业影响的方法研究。此外,气候变化背景下极端天气气候事件对农业生产的影响以及气候变化对农业病虫害的影响研究等仍较薄弱,有待进一步加强和深入。  相似文献   

10.
Agricultural risk management policies under climate uncertainty   总被引:1,自引:0,他引:1  
Climate change is forecasted to increase the variability of weather conditions and the frequency of extreme events. Due to potential adverse impacts on crop yields it will have implications for demand of agricultural risk management instruments and farmers’ adaptation strategies. Evidence on climate change impacts on crop yield variability and estimates of production risk from farm surveys in Australia, Canada and Spain, are used to analyse the policy choice between three different types of insurance (individual, area-yield and weather index) and ex post payments. The results are found to be subject to strong uncertainties and depend on the risk profile of different farmers and locations; the paper provides several insights on how to analyse these complexities. In general, area yield performs best more often across our countries and scenarios, in particular for the baseline and marginal climate change (without increases in extreme events). However, area yield can be very expensive if farmers have limited information on how climate change affects yields (misalignment in expectations), and particularly so under extreme climate change scenarios. In these more challenging cases, ex post payments perform well to increase low incomes when the risk is systemic like in Australia; Weather index performs well to reduce the welfare costs of risks when the correlation between yields and index is increased by the extreme events. The paper also analyses the robustness of different instruments in the face of limited knowledge of the probabilities of different climate change scenarios; highlighting that this added layer of uncertainty could be overcome to provide sound policy advice under uncertainties introduced by climate change. The role of providing information to farmers on impacts of climate change emerges as a crucial result of this paper as indicated by the significantly higher budgetary expenditures occurring across all instruments when farmers’ expectations are misaligned relative to actual impacts of climate change.  相似文献   

11.
东北地区农业应对气候变化的策略与措施分析   总被引:7,自引:0,他引:7       下载免费PDF全文
气候变化的影响与适应已经成为农业生产面临的现实而紧迫的问题。1956-2005年东北地区增温1.5℃,幅度明显高于全国平均水平,给作物生产带来复杂的影响。东北是重要的国家商品粮生产基地,对国家粮食安全起着重要作用。探讨区域层面上适应气候变化的能力建设更具有针对性和现实性。文章分析了近50 a来东北地区气候变化的主要表现及其对农业生产的影响;针对气候变化过程中人类活动对土地利用和温室气体的影响,提出了东北地区适应和减缓气候变化的策略和措施,强调在农业生态、水资源利用、环境保护等多方面综合开展工作,积极采取行动,最终达到维护气候环境、充分利用气候资源的目的,为东北粮食生产安全、农业可持续发展做出贡献。  相似文献   

12.
This study used a quadratic programming sector model to assess the integrated impacts of climate change on the agricultural economy of Egypt. Results from a dynamic global food trade model were used to update the Egyptian sector model and included socio-economic trends and world market prices of agricultural goods. In addition, the impacts of climate change from three bio-physical sectors – water resources, crop yields, and land resources – were used as inputs to the economic model. The climate change scenarios generally had minor impacts on aggregated economic welfare (sum of Consumer and Producer Surplus or CPS), with the largest reduction of approximately 6 percent. In some climate change scenarios, CPS slightly improved or remained unchanged. These scenarios generally benefited consumers more than producers, as world market conditions reduced the revenue generating capacity of Egyptian agricultural exporters but decreased the costs of imports. Despite increased water availability and only moderate yield declines, several climate change scenarios showed producers being negatively affected by climate change. The analysis supported the hypothesis that smaller food importing countries are at a greater risk to climate change, and impacts could have as much to do with changes in world markets as with changes in local and regional biophysical systems and shifts in the national agricultural economy.  相似文献   

13.
气候变化对农业生产与粮食安全影响的新认知   总被引:6,自引:0,他引:6  
IPCC第二工作组在第五次评估报告中客观而审慎地评估了气候变化已经发生和潜在的影响、各个领域与区域的敏感性和脆弱性。针对农业生产与粮食安全,报告表明,气候变化对全球大部分地区作物、畜牧、渔业产生了影响,且负面影响更普遍;不仅影响到生产过程,也影响到非生产系统因素,但这些影响存在区域差异。极端事件(如极端高温)对作物产量、品质及市场价格的负面影响明显。大气中CO2浓度增高有利于作物产量提高,但是与温度、臭氧以及水分利用、病虫草害等协同效应仍然不明确。增强适应可以克服增温对农业的负面影响,并减少粮食损失。关于气候变化对粮食安全非生产系统因素的影响及如何开展适应,还需要搜集更多的证据。  相似文献   

14.
The frequency of extreme weather events, which cause severe crop losses, is increasing. This study investigates the relationship between crop losses and extreme weather events in central Taiwan from 2003 to 2015 and determines the main factors influencing crop losses. Data regarding the crop loss area and meteorological information were obtained from government agencies. The crops were categorised into the following five groups: ‘grains’, ‘vegetables’, ‘fruits’, ‘flowers’ and ‘other crops’. The extreme weather events and their synoptic weather patterns were categorised into six and five groups, respectively. The data were analysed using the z score, correlation coefficient and stepwise regression model. The results show that typhoons had the highest frequency of all extreme weather events (58.3%). The largest crop loss area (4.09%) was caused by two typhoons and foehn wind in succession. Extreme wind speed coupled with heavy rainfall is an important factor affecting the losses in the grain and vegetable groups. Extreme wind speed is a common variable that affects the loss of ‘grains’, ‘vegetables’, ‘fruits’ and ‘flowers’. Consecutive extreme weather events caused greater crop losses than individual events. Crops with long production times suffered greater losses than those with short production times. This suggests that crops with physical structures that can be easily damaged and long production times would benefit from protected cultivation to maintain food security.  相似文献   

15.
16.
Jinwon Kim 《Climatic change》2005,68(1-2):153-168
The effects of increased atmospheric CO2 on the frequency of extreme hydrologic events in the Western United States (WUS) for the 10-yr period of 2040–2049 are examined using dynamically downscaled regional climate change signals. For assessing the changes in the occurrence of hydrologic extremes, downscaled climate change signals in daily precipitation and runoff that are likely to indicate the occurrence of extreme events are examined. Downscaled climate change signals in the selected indicators suggest that the global warming induced by increased CO2 is likely to increase extreme hydrologic events in the WUS. The indicators for heavy precipitation events show largest increases in the mountainous regions of the northern California Coastal Range and the Sierra Nevada. Increased cold season precipitation and increased rainfall-portion of precipitation at the expense of snowfall in the projected warmer climate result in large increases in high runoff events in the Sierra Nevada river basins that are already prone to cold season flooding in todays climate. The projected changes in the hydrologic characteristics in the WUS are mainly associated with higher freezing levels in the warmer climate and increases in the cold season water vapor influx from the Pacific Ocean.  相似文献   

17.
This modeling study addresses the potential impacts of climate change and changing climate variability due to increased atmospheric CO2 concentration on soybean (Glycine max (L.) Merrill) yields in theMidwestern Great Lakes Region. Nine representative farm locations and six future climate scenarios were analyzed using the crop growth model SOYGRO. Under the future climate scenarios earlierplanting dates produced soybean yield increases of up to 120% above current levels in the central and northern areas of the study region. In the southern areas, comparatively small increases (0.1 to 20%) and small decreases (–0.1 to–25%) in yield are found. The decreases in yield occurred under the Hadley Center greenhouse gas run (HadCM2-GHG), representing a greater warming, and the doubled climate variability scenario – a more extreme and variableclimate. Optimum planting dates become later in the southern regions. CO2fertilization effects (555 ppmv) are found to be significant for soybean, increasing yields around 20% under future climate scenarios.For the study region as a whole the climate changes modeled in this research would have an overall beneficial effect, with mean soybean yield increases of 40% over current levels.  相似文献   

18.
气候变化对中国农业生产影响研究展望   总被引:32,自引:0,他引:32  
综述了气候变化背景下中国农业气候资源、农业气象灾害(干旱、洪涝、高温热浪、低温灾害)和农业病虫害的变化趋势与规律,从农业生产潜力变化、作物种植制度变化和作物品质变化等方面阐明了气候变化对中国农业生产的影响事实,分析了气候变化对中国农业生产的可能影响和中国农业生产适应气候变化的对策措施。在此基础上,针对气候变化背景下中国气候资源的时空分布特点及农业生产出现的新情况、新问题,指出了当前中国关于气候变化对农业影响研究存在的不足,提出了未来气候变化对中国农业生产影响研究需要重视的方面,为确保气候变化背景下中国的农业生产安全及粮食安全提供决策支持。  相似文献   

19.
华北地区气候变化及其对水资源的影响   总被引:10,自引:0,他引:10  
根据华北地区近50年的气候、水资源、旱涝灾害面积等资料,对该地区的气候特点及变化趋势、水资源的变化规律与气候变化的相互关系、极端气候事件对水资源的影响及气候变化对农业旱涝的影响进行了分析,并在气候模式预测结果的基础上,简要分析了华北地区未来气候变化对水资源的可能影响,提出了相应的对策建议,从而为实现水资源可持续利用提供科学依据。  相似文献   

20.
已经观测到的气候变化影响是显著的、多方面的。各个领域和地区都存在有利和不利影响,但以不利影响为主,未来的气候变暖将会对中国的生态系统、农业以及水资源等部门和沿海地区产生重大的不利影响。采取适应措施可以减轻气候变化的不利影响,应将适应气候变化的行动逐步纳入国民经济和社会发展的中长期规划中。由于我国科学研究的相对不足和科学认识能力的局限,目前的气候变化影响评估方法和结果还存在很大的不确定性。应当加强区域适应气候变化的案例研究、扩大研究领域、加强极端天气、气候事件影响的研究,以降低影响评估的不确定性,并提出切实可行的适应对策。  相似文献   

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