雷暴预警预报的研究进展

雷暴作为极端天气事件中的一种,不仅常产生强降水、破坏性大风和冰雹等严重的天气灾害,而且还伴有雷电,造成雷击灾害,给工农业生产和人民生活都可带来严重的损失。因此对雷暴的预警预报研究变得尤为重要,也促使其理论、技术及应用都取得了很大的发展。本文对有关雷暴预警预报技术的一些研究结果和进展如雷暴的潜势预报、雷暴的临近预报、雷电活动的观测信息在雷暴天气预警中的指示作用及雷暴云的数值模拟等方面进行了归纳和综述,总结了各方面研究所涉及的重要问题及主要进展,并对未来发展进行展望。     

Hydro-geomorphic hazards and impact of man-made structures during the catastrophic flood of June 2000 in the Upper Guil catchment (Queyras, Southern French Alps)

The Guil River Valley (Queyras, Southern French Alps) is prone to catastrophic floods, as the long historical archives and Holocene sedimentary records demonstrate. In June 2000, the upper part of this valley was affected by a “30-year” recurrence interval (R.I.) flood. Although of lower magnitude and somewhat different nature from that of 1957 (>100-year R.I. flood), the 2000 event induced serious damage to infrastructure and buildings on the valley floor. Use of methods including high-resolution aerial photography, multi-date mapping, hydraulic calculations and field observations made possible the characterisation of the geomorphic impacts on the Guil River and its tributaries. The total rainfall (260 mm in four days) and maximum hourly intensity (17.3 mm h⁻¹), aggravated by pre-existing saturated soils, explain the immediate response of the fluvial system and the subsequent destabilisation of slopes. Abundant water and sediment supply (landsliding, bank erosion), particularly from small catchment basins cut into slaty, schist bedrock, resulted in destructive pulses of debris flow and hyperconcentrated flows. The specific stream power of the Guil and its tributaries was greater than the critical stream power, thus explaining the abundant sediment transport. The Guil discharge was estimated as 180 m³ s⁻¹ at Aiguilles, compared to the annual mean discharge of 6 m³ s⁻¹ and a June mean discharge of 18 m³ s⁻¹. The impacts on the Guil valley floor (flooding, aggradation, generalised bank erosion and changes in the river pattern) were widespread and locally influenced by variations in the floodplain slope and/or channel geometry. The stream partially reoccupied former channels abandoned or modified in their geometry by various structures built during the last four decades, as exemplified by the Aiguilles case study, where the worst damage took place. A comparative study of the geomorphic consequences of both the 1957 and 2000 floods shows that, despite their poor maintenance, the flood control structures built after the 1957 event were relatively efficient, in contrast to unprotected places. The comparison also demonstrates the role of land-use changes (conversion from traditional agro-pastoral life to a ski/hiking-based economy, construction of various structures) in reducing the Guil channel capacity and, more generally, in increasing the vulnerability of the human installations. The efficiency of the measures taken after the 2000 flood (narrowing and digging out of the channel) is also assessed. Final evaluation suggests that, in such high mountainous environments, there is a need to keep most of the 1957 flooded zone clear of buildings and other structures (aside from the existing villages and structures of particular economic interest), in order to enable the river to migrate freely and to adjust to exceptional hydro-geomorphic conditions without causing major damage.     

The 1786 earthquake-triggered landslide dam and subsequent dam-break flood on the Dadu River, southwestern China — Reply

A short reply to discussion by Chanson.     

黄河长江珠江三角洲近30年海平面上升趋势及2030年上升量预测

黄河、长江和珠江三角洲由于地面沉降等原因,过去30年的相对海平面上升率远大于全球或全国海平面上升率（约1.5mm/a）。下一世纪,根据IPCC的最佳估计,至2030年全球海平面将上升18cm。我国三大三角洲,根据目前地面沉降情况、发展趋势及政府的控制措施,估计2030年相对海平面上升量老黄河三角洲（天津地区）为60cm,现代黄河三角洲（山东省东营市地区）为30—35cm,长江三角洲（上海地区）为30—40cm,珠江三角洲20—25cm,以上估计数可供沿海有关决策部门制订今后长远发展规划及拟订政策时的参考。     

Accuracy of forecasting in a Nordic paper mill's supply chain: A case study

The article compares the accuracy of forecasted and actual supply chain cost and price factors in a Nordic paper mill's sales to customers in two large European countries. Empirical longitudinal research data covering the years between 2002 and 2008 were obtained from a large integrated Finnish paper mill, and consisted of sales volumes, paper prices, variable costs, and transport costs. It was expected that the mill would be able to forecast demand, prices and costs accurately, but the empirical findings showed that the forecasts for paper price, demand, and cost varied from one market to another and were not highly accurate. In addition, the forecasting of gross margins seemed to be very inexact. It is concluded that there is a need for more reliable forecasting methods in the paper industry to anticipate economic development as paper demand and costs change.     

西南山地森林变化对洪水频率影响的模拟

森林砍伐和恢复改变了流域洪水形成条件,将影响河流洪水的总量与洪峰形态,但是选择合适的技术来进行准确的分析评价仍然是个难题.采用流域分布式水文数学模型(SWAT)对四川梭磨河径流过程进行模拟,得到不同森林覆被率的洪水过程和洪峰的频率分布.针对各种森林情境下的洪水过程模拟,发现对于中小尺度流域,良好的森林覆被可以减小洪水大小30％～ 40％,而且其中森林覆被率在35％ ～ 40％之内具有最显著的滞蓄洪效益,它与完全的森林覆被对在洪水的影响差异仅在5％以内,这对于我国西南生态保护与恢复工程的实施决策具有重要参考价值.     

Aspiration and reality: flood policy, economic damages and the appraisal process

Research shows that flood damage potential has increased significantly in the last 15 years. At the same time, flood policy has shifted away from simplistic flood defence towards 'living with floods' and 'making space for water'. This paper explores the mis-match between the aspiration in policy ideals, the reality of rising potential economic damages and the inability of the flood risk appraisal process to match the aspiration with the reality. Unless investment appraisal procedures are changed, the increase in damages will undermine policy changes that seek a different pattern of flood risk management, away from economically dominated decision-criteria towards more sustainable objectives.     

基于复杂性测度的中国洪灾受灾面积变化研究

采用复杂性测度方法来进行中国洪涝灾害受灾面积变化的研究。结果表明:(1) 20世纪80、90年代中国洪灾受灾面积及其复杂度均持续上升,说明洪灾剧烈,而且复杂多变、不确定性增加;进入21世纪,两者趋缓或下降,即中国洪涝灾害有所缓解;(2) 从分省区的结果来看,洪灾受灾面积的未来趋势具有区域特征,主要可划分为两个加剧的区域和两个减缓的区域;全国各省市区依据受灾面积趋势可划分为4个等级,在此基础上给出中国的未来洪灾受灾面积趋势图。     

南水北调与山东水资源可持续利用

山东省水资源不足,且分布不均,对经济和生态环境已产生严重影响。南水北调工程是缓解山东水资源紧缺,维持山东水资源可持续利用的根本性措施。建议调整一期一步工程路线,并合理解决污染、南四湖东平湖调蓄、胶东应急工程及资金问题。     

The flood of the Nenjiang river and the Songhua river in 1998 and the comprehensive management of the river basins

ＴｈｅＳｏｎｇｈｕａＲｉｖｅｒ,ｏｎｅｏｆｔｈｅｍａｊｏｒｒｉｖｅｒｓｉｎＮｏｒｔｈｅａｓｔＣｈｉｎａ,ｈａｓｔｗｏｓｏｕｒｃｅｓ：ｔｈｅｎｏｒｔｈｓｏｕｒｃｅｉｓｔｈｅＮｅｎｊｉａｎｇＲｉｖｅｒａｎｄｔｈｅｓｏｕｔｈｓｏｕｒｃｅｉｓｔｈｅＳｅｃｏｎｄＳｏｎｇｈｕａＲｉｖｅｒ．ＴｈｅｔｒｕｎｋｓｔｒｅａｍｏｆｔｈｅＮｅｎｊｉａｎｇＲｉｖｅｒ,ｒｉｓｉｎｇａｔｔｈｅｓｏｕｔｈｅｒｎｆｏｏｔｏｆｔｈｅＹｉｌｅｈｕｌｉＭｏｕｎｔａｉｎ,ｉｓ１３７０ｋｍｌｏｎｇａｎｄｉｔｓｗａｔｅｒｓｈｅｄａｒｅａｉｓ…