共查询到20条相似文献，搜索用时 109 毫秒
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越来越多的证据表明，全球特别是中高纬度的气候在变暖，安徽尤其是淮北地区呈现类同趋势。利用目标决策方法，探讨了安徽未来农业生产发展与气候变化间的适应性及其对策，为政府决策部门提供了科学依据。 相似文献
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以黑龙江省柳河水库为例，选用连续量预报经济效益评价的数学模型，对黑龙江省水库水位。吐气候决策进行调度的经济效益进行了评价。结果表明；气候决策相对于平均值决策效益明显；如果推广到全省２６０座水库，经济效益就更可观了． 相似文献
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采用MCE(Multi-Criteria Evaluation)方法，在台风路径客观综合预报方法研究与业务实验中，根据多家预报的主要结果进行综合评估分析，提出最佳客观综合预报结果以供决策者及预报员参照。取得初步结果：(1)对9711号台风进行了MCE客观综合决策方法的预报试验。结果表明，对于9711号台风生命史中几个关键点的预报，即登陆预报、台风转向北上预报及出海转向预报等以及全程预报，MCE方法取得较佳预报结果。(2)在综合平台上对近10年的疑难路径台风和2000年全年台风进行了MCE方法试验及多种预报结论的对比分析研究。MCE方法预报误差检验结果较好。(3)所提出的模拟预报员预报思维的联想智能模拟方法，以及可操作综合预警平台，为台风路径预报，包括分析、学习、回忆、对比、推理、联想直到形成综合预报结论提供了一个十分有用的工具。(4)讨论的自反馈函数对形成和推演多规则评估决策有一定的实用性。 相似文献
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分析了深度不确定性内涵及其特点,包括情景不确定、决策后果不确定和决策方案不确定,指出了传统洪涝风险决策方法过于依赖于气候变化预测结果,未能充分考虑深度不确定性及提供稳健决策。给出了国际上处理深度不确定性的稳健决策方法理论基础,并介绍了被广泛应用于洪涝风险领域的鲁棒决策、信息差距及适应对策路径3种稳健决策方法。对比分析发现,鲁棒决策法有完备的适应措施定量评估体系但计算量大且不易理解;信息差距法可解决不能以概率表式的不确定性问题,而未考虑适应对策的失效情景;适应对策路径法提供可视化的决策路径,未能充分考虑社会经济的不确定性。提出未来可综合鲁棒决策和适应对策路径优点,为减少不确定性、降低洪涝灾害风险、制定适应气候变化策略提供参考。 相似文献
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平凉地区农作物布局的最佳种植决策 总被引：1，自引：0，他引：1
采用陇东地区及相邻的固原、长武、陇县共18个站1951～2000年的气象资料，计算了各站历年各时段干旱指数，划分了干旱等级，结合全区农作物夏、秋粮、小麦、玉米、高粱、马铃薯、油料种植面积、单产等资料，分析了气候因素与作物产量的关系。选用线性规划和减产率矩阵相结合的方法，建立确定型和随机型种植决策模型，优选出可供实施种植比例的最佳方案。结果表明：不论夏秋作物还是五种作物均在秋春连旱年减产率最大，达30％～40％之间，在无气候干旱年，其减产率最小，为12％～15％。随机型决策接近历年的情况，决策意义不大；确定型决策效果比较显著，其综合减产率普遍少1％-3％，有优化决策价值。虽然确定型优于随机型，但其依赖于长期天气趋势预报的准确程度，应用种植决策还是以随机型与确定型兼用较为稳妥，风险性小。 相似文献
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Seasonal climate prediction for South America with FSU Multi-model Synthetic Superensemble algorithm 总被引：1，自引：0，他引：1
Rosane R. Chaves A. K. Mitra T. N. Krishnamurti 《Meteorology and Atmospheric Physics》2005,89(1-4):37-56
Summary Objective combination schemes of predictions from different models have been applied to seasonal climate forecasts. These schemes are successful in producing a deterministic forecast superior to individual member models and better than the multi-model ensemble mean forecast. Recently, a variant of the conventional superensemble formulation was created to improve skills for seasonal climate forecasts, the Florida State University (FSU) Synthetic Superensemble. The idea of the synthetic algorithm is to generate a new data set from the predicted multimodel datasets for multiple linear regression. The synthetic data is created from the original dataset by finding a consistent spatial pattern between the observed analysis and the forecast data set. This procedure is a multiple linear regression problem in EOF space. The main contribution this paper is to discuss the feasibility of seasonal prediction based on the synthetic superensemble approach and to demonstrate that the use of this method in coupled models dataset can reduce the errors of seasonal climate forecasts over South America. In this study, a suite of FSU coupled atmospheric oceanic models was used. In evaluation the results from the FSU synthetic superensemble demonstrate greater skill for most of the variables tested here. The forecast produced by the proposed method out performs other conventional forecasts. These results suggest that the methodology and database employed are able to improve seasonal climate prediction over South America when compared to the use of single climate models or from the conventional ensemble averaging. The results show that anomalous conditions simulated over South America are reasonably realistic. The negative (positive) precipitation anomalies for the summer monsoon season of 1997/98 (2001/02) were predicted by Synthetic Superensemble formulation quite well. In summary, the forecast produced by the Synthetic Superensemble approach outperforms the other conventional forecasts. 相似文献
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Abstract A static decision‐analytic method is used to investigate the economic value of bivariate ‐ precipitation and temperature ‐ seasonal forecasts of the form currently issued by the U.S. National Weather Service. This method is applied to a corn versus spring wheat choice‐of‐crop decision‐making problem by considering a transect of four counties across the northwestern margin of the North American corn belt. Numerical results indicate that seasonal forecasts of current quality can be of appreciable value (≥$1/ha) for some locations when the optimal action chosen on the basis of climatological information is only marginally preferred to another action. Increases in forecast value follow from hypothetical increases in the quality of both the precipitation and temperature components of the forecasts in the spring wheat region, whereas forecast value increases primarily as a function of the quality of the precipitation forecasts alone in the corn belt region. The results are very sensitive to absolute and relative crop prices. 相似文献
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Observation System Experiments for Typhoon Nida (2004) Using the CNOP Method and DOTSTAR Data 
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下载免费PDF全文 CHEN Bo-Yu 《大气和海洋科学快报》2011,4(2):118-123
This study investigated the influence of dropwindsonde observations on typhoon forecasts. The study also evaluated the feasibility of the conditional nonlinear optimal perturbation (CNOP) method as a basis for sensitivity analysis of such forecasts. This sensitivity analysis could furnish guidance in the selection of targeted observations. The study was performed by conducting observation system experiments (OSEs). This research used the fifth-generation Mesoscale Model (MM5), the Weather Research and Forecasting (WRF) model, and dropsonde observations of Typhoon Nida at 1200 UTC 17 May 2004. The dropsondes were collected under the operational Dropsonde Observations for Typhoon Surveillance near the Taiwan Region (DOTSTAR) program. In this research, five kinds of experiments were designed and conducted:(1) no observations were assimilated; (2) all observations were assimilated;(3) observations in the sensitive area revealed by the CNOP method were assimilated;(4) the same as in (3), but for the region revealed by the first singular vector (FSV) method;and (5) observations within a randomly selected area were assimilated. The OSEs showed that (1) the DOTSTAR data had a positive impact on the forecast of Nida’s track;(2) dropsondes in the sensitive areas identified by the MM5 CNOP and FSV remained effective for improving the track forecast for Nida on the WRF platform;and (3) the greatest improvement in the track forecast resulted from the CNOP-based (third) simulation, which indicated that the CNOP method would be useful in decision making about dropsonde deployments. 相似文献
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利用相似权重集成预报法对辽宁区域12个数值模式预报的降水量进行集成,并投入业务化应用。结果表明：通过对2009年5月1日至10月20日的24 h降水量预报进行TS评分,发现降水集成方法要优于12个集合成员的单个预报,同时也要优于简单的集合平均。试验表明,滞后时间和扩大圈数对集成预报效果影响很大,而单个的集合成员对集成预报效果影响较小。根据试验结果修改集成方法应用方案,按照不同降水量级和预报时效选择扩大的圈数,预报效果好于原方案,对大量级、长时效预报改进更明显,其中25 mm量级预报时效72 h的TS评分增加了20%或以上,具有实际应用价值。 相似文献
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From accessing to assessing forecasts: an end-to-end study of participatory climate forecast dissemination in Burkina Faso (West Africa) 总被引：1，自引：0，他引：1
Carla Roncoli Christine Jost Paul Kirshen Moussa Sanon Keith T. Ingram Mark Woodin Léopold Somé Frédéric Ouattara Bienvenue J. Sanfo Ciriaque Sia Pascal Yaka Gerrit Hoogenboom 《Climatic change》2009,92(3-4):433-460
This study compares responses to seasonal climate forecasts conducted by farmers of three agro-ecological zones of Burkina Faso, including some who had attended local level workshops and others who had not attended the workshops. While local inequalities and social tensions contributed to excluding some groups, about two-thirds of non-participants interviewed received the forecast from the participants or through various means deployed by the project. Interviews revealed that almost all those who received the forecasts by some mechanism (workshop or other) shared them with others. The data show that participants were more likely to understand the probabilistic aspect of the forecasts and their limitations, to use the information in making management decisions and by a wider range of responses. These differences are shown to be statistically significant. Farmers evaluated the forecasts as accurate and useful in terms of both material and non-material considerations. These findings support the hypothesis that participatory workshops can play a positive role in the provision of effective climate services to African rural producers. However, this role must be assessed in the context of local dynamics of power, which shape information flows and response options. Participation must also be understood beyond single events (such as workshops) and be grounded in sustained interaction and commitments among stakeholders. The conclusion of this study point to lessons learned and critical insights on the role of participation in climate-based decision support systems for rural African communities. 相似文献
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Katharine Vincent Andrew J. Dougill Lindsay C. Stringer Tracy Cull 《Climate Policy》2013,13(2):189-202
The importance of climate services, i.e. providing targeted, tailored, and timely weather and climate information, has gained momentum, but requires improved understanding of user needs. This article identifies the opportunities and barriers to the use of climate services for planning in Malawi, to identify the types of information that can better inform future adaptation decisions in sub-Saharan Africa. From policy analysis, stakeholder interviews, and a national workshop utilizing serious games, it is determined that only 5–10 day and seasonal forecasts are currently being used in government decision making. Impediments to greater integration of climate services include spatial and temporal scale, accessibility, timing, credibility and the mismatch in timeframes between planning cycles (1–5 years) and climate projections (over 20 years). Information that could more usefully inform planning decisions includes rainfall distribution within a season, forecasts with 2–3 week lead times, likely timing and location of extreme events in the short term (1–5 years), and projections (e.g. rainfall and temperature change) in the medium term (6–20 years). Development of a national set of scenarios would also make climate information more accessible to decision makers, and capacity building around such scenarios would enable its improved use in short- to medium-term planning. Improved climate science and its integration with impact models offer exciting opportunities for integrated climate-resilient planning across sub-Saharan Africa. Accrual of positive impacts requires enhanced national capacity to interpret climate information and implement communication strategies across sectors.Policy relevanceFor climate services to achieve their goal of improving adaptation decision making, it is necessary to understand the decision making process and how and when various types of weather and climate information can be incorporated. Through a case study of public sector planning in Malawi, this article highlights relevant planning and policy-making processes. The current use of weather and climate information and needs, over various timescales – sub-annual to short term (1–5 years) to medium term (6–20 years) – is outlined. If climate scientists working with boundary organizations are able to address these issues in a more targeted, sector-facing manner they will improve the uptake of climate services and the likelihood of climate-resilient decisions across sub-Saharan Africa. 相似文献
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Seasonal probability forecasts produced with numerical dynamics on supercomputers offer great potential value in managing risk and opportunity created by seasonal variability. The skill and reliability of contemporary forecast systems can be increased by calibration methods that use the historical performance of the forecast system to improve the ongoing real-time forecasts. Two calibration methods are applied to seasonal surface temperature forecasts of the US National Weather Service, the European Centre for Medium Range Weather Forecasts, and to a World Climate Service multi-model ensemble created by combining those two forecasts with Bayesian methods. As expected, the multi-model is somewhat more skillful and more reliable than the original models taken alone. The potential value of the multimodel in decision making is illustrated with the profits achieved in simulated trading of a weather derivative. In addition to examining the seasonal models, the article demonstrates that calibrated probability forecasts of weekly average temperatures for leads of 2–4 weeks are also skillful and reliable. The conversion of ensemble forecasts into probability distributions of impact variables is illustrated with degree days derived from the temperature forecasts. Some issues related to loss of stationarity owing to long-term warming are considered. The main conclusion of the article is that properly calibrated probabilistic forecasts possess sufficient skill and reliability to contribute to effective decisions in government and business activities that are sensitive to intraseasonal and seasonal climate variability. 相似文献
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决策树方法在一次历史异常雷电活动中的预报能力检验 总被引：1，自引：0，他引：1
利用ncep1°×1°再分析资料和四川闪电定位仪监测网的监测资料,基于四川雷电潜势预报决策树的三类预报因子,针对2008年9月22～25日四川盆地西北部连续性雷电活动过程,重点分析了连续性雷电活动的环流背景和主要天气影响系统、热力结构特征、动力结构特征,检验了基于决策树方法筛选出的雷电潜势预报因子对连续性雷电活动的预报能力.结果表明：1）“9·23”连续性雷暴天气过程存在对流性雷暴以及副高和地面冷空气共同作用下形成的雷暴时段.雷暴区内始终存在着高能不稳定的热力条件,具有“对流层中低层正涡度、对流层高层负涡度”的典型雷暴动力结构.2）雷电潜势预报决策树的三大类预报因子能较好地预报本次雷电活动. 相似文献