Targeting seasonal climate forecasts for integration into household level decisions: the case of smallholder farmers in Lesotho   总被引：2，自引：0，他引：2  

Gina Ziervogel 《The Geographical journal》2004,170(1):6-21

Seasonal climate forecasts have been promoted as a means to increase the resilience of marginal groups in Africa. The manifestations of this are still to be seen. This paper argues that successful dissemination and adoption of the forecast requires an in-depth profile of the characteristics and needs of user groups. The case study of a mountainous village in southern Lesotho is used to highlight the decisions which one group of marginal users – smallholder farmers – might make in response to the forecast. A participatory role-play exercise explores what information households presently receive and how new climate forecast information could be integrated into seasonal decision making. Results show that there are a number of low-input options available to these farmers for responding to the forecast. Adoption, however, is going to require repeated exposure to the forecast in conjunction with forecast development that is suited to users' needs. The case study is linked back to the larger scale by suggesting paths that seasonal climate forecast development could take if it is to contribute to improving livelihood sustainability among marginal groups.  相似文献   

广东“18.8”季风槽极端降水事件对流尺度集合预报分析     

陈训来  朱科锋  王德立  陈元昭  王蕊  杨楠  张华龙 《热带气象学报》2024,(1):11-22

受季风槽影响,2018年8月30—31日华南地区出现一次极端暴雨过程,单日站点累计降水量达1?056.7 mm,刷新了广东有历史纪录以来新的极值。对于此次极端降水事件,常用的业务模式包括欧洲中期天气预报中心全球模式（ECMWF）、日本气象厅谱模式（JMA）和中国气象局广东快速更新同化数值预报系统（CMA-GD）,都低估了降水强度。利用深圳市气象局业务对流尺度集合预报系统分析了此次特大暴雨过程,结果表明：对流尺度集合预报系统对本次特大暴雨过程具有比较好的预报能力,概率匹配平均最大雨量达348.7 mm·(24 h)-1,集合平均的强降水中心和观测基本一致,观测极值附近区域发生大暴雨（≥150 mm）概率最大值达到80%。选取了较“好”和较“差”集合成员预报进行对比分析,发现较“好”成员预报的强降水中心位置和观测基本一致,而较“差”成员预报的降水中心位置则偏向福建地区。较 “好”成员预报出莲花山南侧地面中尺度辐合线较长时间的维持和缓慢移动,导致强降水雨团在莲花山脉附近不断地触发和维持,同时地形的阻挡作用使得对流系统在地形附近区域持续维持,造成了罕见的特大暴雨;而较“差”成员辐合区位于莲花山以北,对流形成后向东、向北移动,最终导致强降水预报位置偏向福建地区。  相似文献   

冬季黔北境内云贵准静止锋影响下最高气温预报订正方法研究          下载免费PDF全文

罗晨艺 《中低纬山地气象》2023,47(5):52-56

本文为探索静止锋位于遵义上空不同位置时,各城镇精细化预报考核站点当日高温的规律,通过普查2009至2020年12月到次年2月间14时、17时地面天气图,并结合探空资料、卫星云图等资料,筛选出云贵准静止锋（以下简称为静止锋）位于遵义境内时的所有个例,分型统计不同类型个例对应的白天最高温、EC2m温度预报数据,EC细网格850hPa温度,计算不同温度预报方法下的准确率,并分析是否可继续订正。结果表明：（1）离锋面越远,温度的预报准确率越高,基于客观预报方法的可订正性越强,实际业务中可以参考本文分析得到的各站点数据。（2）当静止锋呈Ⅰ1型时,遵义市西部站点用EC预报当日20时的850hPa温度进行预报（以下简称850hPa温度预报方法）准确率较高,北部、东部站点可用EC2m最高温度进行订正（以下简称2m温度订正方法）。（3）当静止锋呈Ⅰ2型时,可以同时参考850hPa温度预报方法和2m温度订正方法,订正后准确率高。（4）当静止锋为Ⅱ2型时,对于离锋面较远的东部、南部可着重使用2m温度订正方法。  相似文献   

基于TIGGE资料的北半球地面气温预报的统计降尺度研究          下载免费PDF全文

陈晓龙  智协飞 《大气科学学报》2014,37(3):268-275

基于TIGGE(THORPEX Interactive Grand Global Ensemble,全球交互式大集合)资料中欧洲中期天气预报中心(European Centre for Medium-Range Weather,ECMWF)、日本气象厅(Japan Meteorological Agency,JMA)、美国国家环境预报中心(National Centers for Environmental Prediction,NCEP)和英国气象局(United Kingdom Met Office,UKMO)4个中心的北半球地面2 m气温集合平均预报资料,利用插值技术与回归分析,并引入了消除偏差集合平均(bias-removed ensemble mean,BREM)和多模式超级集合(superensemble,SUP)方法进行统计降尺度预报研究。结果表明,在2007年夏季3个月中,4个单中心的降尺度预报明显地改善了预报效果。引入SUP和BREM两种集成预报方法后,预报误差得到进一步减小。对比综合表现最好的单中心ECMWF的预报,1~7 d的降尺度预报误差改进率均达20%以上。研究还发现,引入SUP方法的降尺度预报效果优于引入BREM方法的降尺度预报,利用双线性插值方法在上述两方案中的预报效果优于其他3种插值方法。  相似文献   

江苏—南黄海地区M≥6强震有序网络结构及其预测研究   总被引：2，自引：1，他引：1  

门可佩 《南京气象学院学报》2014,6(3):268-274

基于TIGGE（THORPEX Interactive Grand Global Ensemble,全球交互式大集合）资料中欧洲中期天气预报中心（European Centre for Medium-Range Weather,ECMWF）、日本气象厅（Japan Meteorological Agency,JMA）、美国国家环境预报中心（National Centers for Environmental Prediction,NCEP）和英国气象局（United Kingdom Met Office,UKMO）4个中心的北半球地面2m气温集合平均预报资料,利用插值技术与回归分析,并引入了消除偏差集合平均（bias-removed ensemble mean,BREM）和多模式超级集合（superensemble,SUP）方法进行统计降尺度预报研究.结果表明,在2007年夏季3个月中,4个单中心的降尺度预报明显地改善了预报效果.引入SUP和BREM两种集成预报方法后,预报误差得到进一步减小.对比综合表现最好的单中心ECMWF的预报,1～7d的降尺度预报误差改进率均达20％以上.研究还发现,引入SUP方法的降尺度预报效果优于引入BREM方法的降尺度预报,利用双线性插值方法在上述两方案中的预报效果优于其他3种插值方法.  相似文献   

甘肃省黑河干流中游地区泉水动态特征及预报          下载免费PDF全文

赵建忠  丁宏伟  徐大录 《甘肃地质》2010,(3):49-54

在简述区域水文地质条件的基础上,依据1986～2007年泉水流量系列观测资料,详细论述了区内下降泉、上升泉的年内和多年动态变化特征,对比分析了1967年、1984年、2006年测区各泉域泉水量和泉水总量的时空分布规律和变化特征。利用已有的潜水二维流水量数学模型,推递并建立了利用泉点周围节点水头(水位)预报泉水流量的数学模型,并对测区泉水总量未来15年的变化趋势进行了预报。结果表明,在现状节水灌溉条件下,由于出山径流量的增加和地下水开采量的减少,未来黑河干流中游地区的泉水资源基本处于稳定状态。  相似文献   

贵州兴旺煤矿开采地表塌陷预测方法探讨     

隋建红  李超 《山东地质》2012,(6):25-27

以贵州六枝特区兴旺煤矿地表塌陷为例,采用概率积分法作为地表移动及变形预测的模式,选取下沉系数、主要影响角、主要影响半径和水平移动系数为地表移动参数,计算得出井田开采后地表最大下沉值为1425．3mm,影响面积约1．85km^2。并比较说明除移动参数外各类煤柱的留设也是其中需要考虑的因素。  相似文献   

Geophysical flows under location uncertainty,Part I Random transport and general models     

V. Resseguier  E. Mémin  B. Chapron 《地球物理与天体物理流体动力学》2017,111(3):149-176

A stochastic flow representation is considered with the Eulerian velocity decomposed between a smooth large scale component and a rough small-scale turbulent component. The latter is specified as a random field uncorrelated in time. Subsequently, the material derivative is modified and leads to a stochastic version of the material derivative to include a drift correction, an inhomogeneous and anisotropic diffusion, and a multiplicative noise. As derived, this stochastic transport exhibits a remarkable energy conservation property for any realizations. As demonstrated, this pivotal operator further provides elegant means to derive stochastic formulations of classical representations of geophysical flow dynamics.  相似文献   

Geophysical flows under location uncertainty,Part II Quasi-geostrophy and efficient ensemble spreading     

V. Resseguier  E. Mémin  B. Chapron 《地球物理与天体物理流体动力学》2017,111(3):177-208

Models under location uncertainty are derived assuming that a component of the velocity is uncorrelated in time. The material derivative is accordingly modified to include an advection correction, inhomogeneous and anisotropic diffusion terms and a multiplicative noise contribution. In this paper, simplified geophysical dynamics are derived from a Boussinesq model under location uncertainty. Invoking usual scaling approximations and a moderate influence of the subgrid terms, stochastic formulations are obtained for the stratified Quasi-Geostrophy and the Surface Quasi-Geostrophy models. Based on numerical simulations, benefits of the proposed stochastic formalism are demonstrated. A single realization of models under location uncertainty can restore small-scale structures. An ensemble of realizations further helps to assess model error prediction and outperforms perturbed deterministic models by one order of magnitude. Such a high uncertainty quantification skill is of primary interests for assimilation ensemble methods. MATLAB^® code examples are available online.  相似文献   

A review of advances in flash flood forecasting   总被引：1，自引：0，他引：1  

H. A. P. Hapuarachchi  Q. J. Wang  T. C. Pagano 《水文研究》2011,25(18):2771-2784

Flash flooding is one of the most hazardous natural events, and it is frequently responsible for loss of life and severe damage to infrastructure and the environment. Research into the use of new modelling techniques and data types in flash flood forecasting has increased over the past decade, and this paper presents a review of recent advances that have emerged from this research. In particular, we focus on the use of quantitative precipitation estimates and forecasts, the use of remotely sensed data in hydrological modelling, developments in forecasting models and techniques, and uncertainty estimates. Over the past decade flash flood forecast lead‐time has expanded up to six hours due to improved rainfall forecasts. However the largest source of uncertainty of flash flood forecasts remains unknown future precipitation. An increased number of physically based hydrological models have been developed and used for flash flood forecasting and they have been found to give more plausible results when compared with the results of conceptual, statistical, and neural network models. Among the three methods for deciding flash flood occurrence discussed in this review, the rainfall comparison method (flash flood guidance) is most commonly used for flash flood forecasting as it is easily understood by the general public. Unfortunately, no existing model is capable of making reliable flash flood forecasts in urban watersheds even though the incidence of urban flash flooding is increasing due to increasing urbanisation. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献