上海强对流智能预报业务新技术研究进展

强对流天气系统发展剧烈,常造成严重的暴雨、雷电、大风和冰雹等灾害。对强对流天气的准确预报一直是国际气象领域研究的难点和瓶颈问题,也是大城市防灾减灾关注的重点。强对流预报技术的发展已经从单纯依赖于雷达的图像识别,发展到雷达、卫星、高分辨率数值模式以及人工智能大数据预测融合应用的新阶段。在回顾国际强对流预报技术进展的基础上,介绍了上海气象业务部门近年来攻关研发的雷达自适应组网观测、雷达外推短临预测和数值预报误差机器学习订正等关键新技术及集成建立的上海强对流智能监测预报系统。这些技术成果的业务应用,在城市防灾减灾和精细化治理中已发挥了重要作用,可供相关研究人员参考。     

新疆喀什西部新一代天气雷达产品的冰雹预警指标研究

2010年以来喀什地区冰雹频繁,严重危害当地农业生产. 通过整理分析2009-2012年喀什新一代天气雷达监测资料,结合我国中东部地区基于雷达监测的冰雹预警指标,经过对喀什西部的18次冰雹天气过程中新一代天气雷达监测预警指标的分析,归纳出了喀什西部新一代雷达产品的冰雹预警指标：（1）组合反射率≥50 dBz;（2）回波顶高≥9 km;（3）云体垂直液态水含量≥20 kg·m^-2. 根据该预警指标对喀什西部2011-2012年冰雹过程进行回报预警,准确率达到84.6%. 以有详细降雹时间记录的14次冰雹过程为例,分析喀什西部基于雷达监测产品的冰雹预警时效,14次个例中冰雹预警时效平均为27 min. 选取2012年5月13日、5月23日和2013年6月18日3次强冰雹过程个例,分析冰雹出现前后喀什新一代天气雷达的连续监测资料表明：3次过程中降雹开始时间对应雷达监测值达到最大（高）值时刻;组合反射率与回波顶高首先达到预警指标,垂直液态含水量达到预警指标的时间滞后11~19 min;3项雷达产品均达到冰雹预警指标的时间比实际发布冰雹预警时间早7~17 min,喀什西部冰雹预警时效潜力可以增加到30 min以上. 在喀什西部,应用新一代天气雷达监测产品开展冰雹实时预警业务是可行的,对提高当地冰雹灾害防御能力提供了有力的技术支持.     

中国气象科学技术发展战略研究

依据《中国气象事业发展战略研究重大科学技术问题卷》［1］的概述,主要从天气学理论与预报技术、气候系统与全球变化、人工影响天气、大气化学、大气物理学,以及综合探测技术与外场观测试验等方面,分析气象科学发展的背景、现状和社会需求,指出气象科学发展中需要了解的关键科学和技术问题,并制定中国气象科学技术长期发展目标和确定重点研究领域,其中特别强调了与中国区域天气、气候和气候变化问题关系密切的气象科学问题,并在气象科学理论体系的建立、天气预报和气候预测手段的改进、全球气候系统观测的实施、多学科的交叉融合等方面提出措施和建议。     

中国对流性天气现象观测资料质量控制及其年、季节特征分析

基于2 474个国家级气象台站1954-2015年观测的对流性天气现象（包括雷暴、闪电、冰雹、大风）数据,进行了有效的质量控制,并采用气候统计学方法,研究了中国对流性天气的时空变化特征和气候趋势。结果表明：全国平均的雷暴、闪电、冰雹、大风发生频率分别为11.0%、6.8%、0.33%和3.8%,且季节变化明显。我国雷暴、闪电日数自北向南基本呈逐渐增多的格局。在内蒙古地区、青藏高原、沿海地区等三个平均风速较大的地区,发生大风天气现象的日数也相应较多。对流性天气现象年发生日数呈下降趋势。分别有68.3%、67.5%、0.8%、41.6%台站雷暴、闪电、冰雹、大风日数年变化存在显著减少趋势。     

南疆近60 a来冰雹灾害时空变化特征分析

冰雹是新疆主要灾害性天气之一, 利用新疆南疆各地州1949-2008年发生的冰雹频次及其造成的受灾农田面积、 经济损失、 死亡牲畜等资料, 分析了南疆冰雹频次时空变化特征及各县市雹灾灾情.结果表明: 南疆冰雹发生频次近60 a间呈明显上升趋势, 1950年代至1980年代中期发生频次较低, 1986年开始发生频次显著上升, 至1991年达最高值, 由1996年起又减少到2003年谷底.冰雹发生主要集中在3-10月, 其中6月频次最多, 年均3.6次, 其次5月为3.1次. 巴州、 阿克苏、 喀什和克州以春末到夏季型降雹为主, 和田以春季型降雹为主.冰雹一天之内多发生在白天到傍晚时段, 持续时间多为1~20min. 南疆冰雹空间分布上西北部多于东南部, 山脉的背风坡多于迎风坡, 山间盆地多于开阔平原.对各地州而言, 阿克苏冰雹发生频次最多, 属于严重雹灾区; 喀什和巴州次于阿克苏, 属于重雹灾区; 克州与和田冰雹发生频次较少, 属于中雹灾区. 冰雹受灾农田面积和经济损失随着工农业生产总值的增长而增加, 而且增长速度比经济增长速度快. 建议加大防雹投入力度, 建立人工防雹系统, 以减少雹灾损失, 遏制工农业发达地区雹灾损失严重和随着国民经济的增长雹灾损失增加的现象.     

普定的冰雹与“冰雹重力波预警系统”在防雹中的应用效果分析

冰雹是普定县的主要气象灾害之一。为了解普定洋雹活动的规律，减轻冰雹对我县国民为的损失，本文分析了普定冰雹天气的月和季度分布，降雹的时间和强度，冰雹的路径及多雹的原因，介绍了１９９３－１９９５年应用“冰雹重力波预警系统”为一高新科技项目在防灾减灾中取得的显著。     

全天候卫星微波观测资料变分同化研究进展

云和降水区微波观测包含大量与天气系统,特别是台风、暴雨等灾害性天气系统发生发展密切相关的大气信息,因此微波资料的全天候同化应用成为当前数值预报领域的热点研究问题。过去20年间,全球几大数值预报中心逐步开展了全天候同化技术的研究和业务应用,证实了全天候卫星微波观测资料能够改进模式中的质量、风场、湿度以及云和降水场的初始信息,从而改进数值预报模式的预报效果。通过梳理和评述全天候卫星微波观测资料同化方法,分析其中的关键技术问题和目前存在的困难和挑战,为未来在我国数值天气预报领域开展全天候同化研究提供依据。随着我国新一代数值天气预报模式的发展应用,加强我国全天候资料同化技术的研究将会在业务中发挥更大的科学效益和应用效益。     

不同天气类型广东大气超级站细粒子污染特征初步研究

2012年5月至7月期间,以广东大气超级监测站为观测平台,利用单颗粒气溶胶质谱仪(SPAMS)和其他多种环境监测仪器对大气污染现象进行高时间分辨的长期连续观测。以能见度和相对湿度为参考,将天气类型划分为2次灰霾、1次暴雨和多次晴朗天气过程。观测结果表明,SPAMS捕获的颗粒物数浓度与PM2.5和PM1的相关性(R2)分别达到0.538和0.448,呈现出一定的相关性。大气颗粒物浓度在不同天气条件下,浓度变化较大,其中,灰霾天气下,PM2.5和PM1浓度最大小时均值分别达到0.132 ng/m3和0.094 ng/m3。观测结果表明,粒径处于600~800 nm的细颗粒物对该区域的灰霾形成过程起了最为关键的作用。该地区的大气颗粒物类型主要可分为7种:元素碳(EC)、有机碳(OC)、元素-有机碳混合(ECOC)、大分子有机碳(HMOC)、海盐(Na-K)、富钾颗粒(K-rich)和富铅颗粒(Pb-rich)。灰霾天气,各类型颗粒物数量浓度均有一定程度的增加,其中以EC和K-rich的增加最为明显。分析表明,第一次灰霾主要是由于大气光化学反应起到主导作用,而生物质燃烧又增大了灰霾程度;第二次灰霾过程,生物质燃烧产生的影响更大。     

米仓山前多层滑脱和基底隆升叠加变形构造特征与演化

正米仓山构造带位于扬子地块的西北部,为其内部的一构造单元,具有特殊大地构造位置。前人对米仓山构造变形特征做了大量的研究,但其变形模式与动力学模型一直以来都存在争议。本文综合运用详细野外地质观测,地震资料几何学解析和构造变形特征分析等手段方法开展了新一轮地质建模,提出了米仓山前带具有多层滑脱和基底隆升掀斜冲断叠加复合的变形模式。多层滑脱变形表现为米仓山前发育早三叠世嘉陵江组,二叠系,     

新疆冰雹分区预报方法研究

利用1981-2011年的气象观测数据,普查分析了位于新疆北疆沿天山一带的奎屯河-玛纳斯河流域和位于南疆中天山南麓的阿克苏河流域两大防雹区长序列降雹个例的环流形势背景和天气条件,把两地的主要降雹环流型归纳为中亚低涡(槽)型、巴尔喀什湖低涡(槽)型、西西伯利亚低涡(槽)型和锋区短波槽型等4种类型,并根据两地各环流型降雹的三度空间配置及环境条件,研制出了6种降雹概念模型.同时,筛选出8个有指示意义、稳定可靠的对流因子作为冰雹预报因子,建立了两地各环流型多指标叠套法的冰雹分区、定量(强)预报方法.该方法实际应用效果显著,可以推广到新疆其他重点降雹区域应用.     

1970-2013年南疆渭干河-库车河流域绿洲冰雹时空变化特征和棉花受灾分析

渭干河-库车河绿洲是南疆地区主要棉花生产基地之一, 随着气候变化和棉花种植面积的日益扩大, 雹灾对棉花生产的危害日趋严重. 利用该地区4个气象站44 a逐一地面降雹过程资料和33 a灾情信息, 对冰雹时空变化特征、活动规律、强度、受灾面积和影响因素等进行研究. 结果表明: 降雹空间分布为北部靠山地带多于南部平原地带, 受灾面积的空间分布则相反; 降雹以周期短、强季节性特征为主, 各县中等以上降雹天气占80%以上, 降雹趋于高发和强发的态势. 降雹频次与气温和降水呈较好的相关性, 冰雹多发年气温偏低、降水偏多, 冰雹少发年气温偏高、降水偏少. 位于南部靠近沙漠的沙雅县受灾最为严重, 雹灾与降雹强度、地域、季节和作物面积及类型等有关, 该地区棉花受灾机率大.     

Hailstorm Loss Modelling and Risk Assessment in the Sydney Region,Australia

This paper summarises work undertaken at the Natural Hazards ResearchCentre with regard to the compilation, climatological analysis and lossmodelling application of hailstorm data for the greater Sydney region. Itdiscusses the results from two associated research areas: ENSO-relatedclimatological analysis of hailstorm data, and insurance sector orientedrisk assessment of hail losses in the Sydney basin. The two complementaryprojects led to the development of HailAUS, the first hail loss model for amajor urban area in Australia. The hazard occurrence module of the hailloss model is based on a comprehensive, good quality hail data set, whoseinterannual variability has previously been analysed with regard to the ENSOsignal. The paper presents the major results of the local hail data climatology,and outlines the structure of the hail loss model. The important practicalapplications that result from the collection and analysis of good qualityclimatological data are noted.     

A new physically based stochastic event catalog for hail in Europe

Hailstorms represent one of the major sources of damage and insurance loss to residential, commercial, and agricultural assets in several parts of Central Europe. However, there is little knowledge of hail risk across Europe beyond local historical damage reports due to the relative rarity of severe hail events and the lack of uniform detection methods. Here we present a new stochastic catalog of hailstorms for Europe. It is based on satellite observations of overshooting cloud tops (OT) that indicate very strong convective updrafts and hail reports from the European Severe Weather Database (ESWD). Historic hail events are defined based on OT detections from satellite infrared brightness temperatures between 2004 and 2011 for the warm seasons (April–September). The satellite-based historical event properties are complemented by hailstone observations from ESWD to stochastically simulate more than 1 million individual events with an event footprint resolution of 10 km. The final hail event catalog presented in this paper is the first one with a spatial event distribution that is based on a single homogeneous observation source over Europe. Areas of high hail probability or hail risk are found over Central and Southern Europe, including mountainous regions such as the Alps or the Pyrenees. Another region of relatively high hail risk is present over central Eastern Europe.     

1961-2014年新疆冰雹灾害时空分布特征

通过整理、 普查得到1961-2014年新疆以县为单位的雹灾频次、 受灾面积、 经济损失的样本序列, 在此基础上定义了表征雹灾程度的无量纲数损失指数. 结果表明: 新疆雹灾频次集中出现在阿克苏地区、 博州、 石河子地区, 5-8月为多发期, 6月最多. 雹灾的年际变化呈现出2～5 a的短周期和7～8 a的长周期, 20世纪60、 70年代为新疆雹灾的少发期, 1980-1994年、 2001-2014年为雹灾的两个集中高发期. 按照地区累计灾损指数将新疆雹灾划分为5个等级, 阿克苏地区属严重雹灾区, 喀什地区、 塔城地区、 伊犁州属重雹灾区, 石河子地区、 博州、 昌吉州、 巴州、 克拉玛依市属中雹灾区, 阿勒泰地区、 克州、 和田地区、 哈密地区属轻雹灾区, 吐鲁番地区和乌鲁木齐市属微雹灾区.     

新疆冰雹灾害经济损失评估及风险区划研究

基于1984-2014年新疆雹灾受灾面积、总成灾面积、农作物播种面积、新疆生产总值及以县为单位的雹灾频次等统计数据,构建雹灾经济损失指标和风险度指标,进行新疆冰雹灾害评估研究。其中雹灾经济损失指标可用于评价新疆雹灾经济损失的趋势变化,风险度指标可借助GIS空间信息处理技术形成新疆雹灾风险区划。研究表明：雹灾经济损失总体呈波动上升趋势,且受环境不稳定度的影响较大,二者保持着较好的正相关性。新疆冰雹灾害总体以中、低度风险为主,高风险次之。高风险区主要集中在喇叭形河谷地带的伊犁地区及其两侧的阿克苏、博州等地,建议通过调整农业产业结构、提升人工防雹能力等方式降低上述区域的雹灾损失。     

Radar research of hailstorm formation and development over the central part of Northern Caucasus (Russia). Organization and main results of the regional hail suppression projects

The results of the analysis of long-term radar research of the hailstorms over the central part of the Northern Caucasus are presented. Radar observations which formed the basis of experimental material were carried out continuously from the moment of the first radar echo registration until complete dissipation of the hailstorm. The computerized system of collecting, processing and the analysis of the radar information was used. Time discretization of the radar parameters of the full spatial observation averaged 3 min. Statistical sampling of radar data included 392 hail cells, for each of which the time distributions of the radar parameters both measured and calculated using the computerized system were compiled. Distribution of the hailstorms first radar echo formation zones over the observation region was compiled. Areas with the maximum frequency of the hailstorms first radar echo formation were defined. The hailstorm trajectories were analyzed. Four main types of hail cell trajectories were selected, which included 86 % of the supercells and 64 % of the long-lived multicells. The dynamic parameters of the hail core formation and development were analyzed. The hail storm characteristics of the Northern Caucasus are compared to the hail storms of Mendoza, Argentina, and Alberta, Canada. The bases of the organization of regional hail suppression services which use the rocket technology of cloud seeding are presented. The results of the cloud seeding operations during recent years are shown.     

Urban hailstorms: a view from Alberta

Urban hailstorms are rarely studied in detail. This work documents five urban storms in Alberta where damage has, on three occasions, set the record for Canada's most costly natural disaster. Information from newspapers, insurance companies, and disaster assistance programs was utilized to supplement meteorological records and information obtained from public surveys.The record-breaking hail swath which accompanied the 1987 Edmonton tornado was mapped using over 800 responses to an unprecedented newspaper survey. Tennis ball sized hail struck 125 km² of the city. Record-sized hailstones for Alberta were collected. Citizens' measurements of giant hailstones were compared to laboratory measurements. The rural storms were tracked using lightning detector information and damage was mapped using crop insurance and disaster assistance claims. The tornado-bearing storm was found to have a unique track.A late-season hailstorm which struck Calgary in 1991 was mapped using homeowner insurance claims organized by postal areas. Nine out of thirty areas had claims rates exceeding 50%, mainly for shingle replacement. Experiences of claims adjustors and an informal public survey were also utilized. Rural storms were mapped using weather radar and crop losses. The radar beam was strongly attenuated when it passed through hail-bearing storms and, thus, its ability to detect large hail was compromised.Weather conditions, urban and rural damaged areas, and insurance payments were compared for all five local hailstorms. These storms were discussed within the context of the long history of Alberta hail research and current trends in technology implementation. Forecasting of these hailstorms using conventional severe weather indicators was difficult in Calgary because of that city's proximity to the mountains. Hailstorms that struck Munich, Denver, and Toowoomba (Australia) were also discussed, and the hailstones collected from the great Munich storm were compared to those collected from the Edmonton storms.     

Radar research of hailstorm formation and development over the central part of Northern Caucasus (Russia). Organization and main results of the regional hail suppression projects

The results of the analysis of long-term radar research of the hailstorms over the central part of the Northern Caucasus are presented. Radar observations which formed the basis of experimental material were carried out continuously from the moment of the first radar echo registration until complete dissipation of the hailstorm. The computerized system of collecting, processing and the analysis of the radar information was used. Time discretization of the radar parameters of the full spatial observation averaged 3 min. Statistical sampling of radar data included 392 hail cells, for each of which the time distributions of the radar parameters both measured and calculated using the computerized system were compiled. Distribution of the hailstorms first radar echo formation zones over the observation region was compiled. Areas with the maximum frequency of the hailstorms first radar echo formation were defined. The hailstorm trajectories were analyzed. Four main types of hail cell trajectories were selected, which included 86 % of the supercells and 64 % of the long-lived multicells. The dynamic parameters of the hail core formation and development were analyzed. The hail storm characteristics of the Northern Caucasus are compared to the hail storms of Mendoza, Argentina, and Alberta, Canada. The bases of the organization of regional hail suppression services which use the rocket technology of cloud seeding are presented. The results of the cloud seeding operations during recent years are shown.

     

BP神经网络在古气候序列重建中的应用

当前小区域的古气候变化研究受模拟资料分辨率和可靠性的严重制约.为了将大区域的气候模拟资料应用到小区域的古气候研究中去,亟待建立有效的降尺度方法.为此以徽鄂地区为例,建立了一个3层BP神经网络拟合模型,利用相关气象要素作为拟合因子,拟合并重建了该地区近千年来1月、7月和年平均的温度和降水序列,通过与观测及模拟资料的对比分析发现,该模型拟合及重建的近千年气候序列有较高的精度和可靠性,能反映小区域气候的年际和年代际变化信号,提高了模拟资料对小区域气候变化的刻画能力.