大气物理与人工影响天气

云物理与人工影响天气研究进展

Advances in Research on Cloud Physics and Weather Modification

1 人工影响天气机理与方法

1 Mechanism and method of weather modification

1.1 Raindrop size distribution characteristics for tropical cyclones and Meiyu-Baiu fronts impacting Tokyo,Japan

Tropical cyclones and meiyu-baiu fronts,as the two main synoptic systems over East Asia,bring heavy rain during summers,but their long-term and vertical raindrop size distribution (RSD) features over the midlatitude Japan Islands are limited.Radar-based quantitative precipitation estimation (QPE) techniques require RSD observations.In this study,five-year observations from Tokyo with a ground-based impact Joss-Waldvogel disdrometer (JWD) and a vertically pointing micro rain radar (MRR) with a vertical range of 0.2–6.0 km were used to study the vertical structures of RSD and QPE parameters.The results showed that the convective rain associated with tropical cyclones had a maritime nature,while the rain associated with the meiyu-baiu front had a continental nature.The rain associated with tropical cyclones had a relatively higher concentration of raindrops and a larger average raindrop diameter than the rain associated with the meiyubaiu front.TheZ–R(radar reflectivity-rain rate) relationships (Z=ARb) based on the JWD data for tropical cyclones,the meiyu-baiu front and total summer rainfall in Tokyo wereZ=189R1.38,Z=214R1.35andZ=21 2R1.33,respectively.When theZ–Rrelationships obtained in this study were used to replace the operational relationship of Z=300R1.4,the standard deviation of the rain rate was reduced from 5.50 mm h−1(2.34 mm h−1) to 2.34 mm h−1(1.32 mm h−1) for typhoon (meiyu-baiu front) rainfall,although the change for total summer rainfall was small.In addition,with increasing height below 4 km,the value ofAandbdecreased.(Chen Yong,Duan Jing,An Junling,Liu Huizhi)

1.2 Aircraft measurement campaign on summer cloud microphysical properties over the Tibetan Plateau

We reported the first aircraft campaign on summer cloud microphysical properties conducted in July of 2014 over the Tibetan Plateau during the Third Tibetan Plateau Atmospheric Scientific Experiment (TIPEXIII),and demonstrated that the summer clouds over the Tibetan Plateau were primarily characterized as mixed-phase cumulus clouds induced by strong solar radiation heating.Moreover,the characteristic number concentration of cloud droplets (2−50 μm in diameter) in developing cumuli was around 10 cm−3,which was about 1−2 orders of magnitudes lower than those in other continent and ocean regions,and that for large drops (＞50 μm in diameter) was around 10−3cm−3,which was also lower than those in other regions.The droplet spectrum distributions (DSDs) of cloud drops were much wider than those in other regions,indicating that the cumulus clouds over the plateau could form precipitation easier than those in other regions.Ice microphysics was characterized as very active glaciation and riming processes with high supercooled water content,which caused the formation of high concentration of graupel particles in clouds.The findings of this study suggest that these unique cloud microphysical properties formed by the high topography and clean environment of the Tibetan Plateau could induce higher precipitation efficiency when airflow passed over the plateau,so that the plateau could act as a regional“water tower”.(Chang Yi,Guo Xueliang,Tang Jie,Lu Guangxian)

1.3 A numerical investigation on microphysical properties of clouds and precipitation over the Tibetan Plateau in summer 2014

In order to improve our understanding of microphysical properties of clouds and precipitation over the Tibetan Plateau (TP),six cloud and precipitation processes with different intensities during the Third Tibetan Plateau Atmospheric Scientific Experiment (TIPEX-III) from 3 July to 25 July 2014 in the Naqu region of the TP are investigated by using the high-resolution mesoscale Weather Research and Forecasting (WRF) model.The results show unique properties of summertime clouds and precipitation processes over the TP.The initiation process of clouds is closely associated with strong solar radiative heating in the daytime,and summertime clouds and precipitation show an obvious diurnal variation.Generally,convective clouds would transform into stratiform clouds with an obvious bright band and often produce strong rainfall in midnight.The maximum cloud top can reach more than 15 km above sea level and the velocity of updraft ranges from 10 to 40 m s−1.The simulations show high amount of supercooled water content primarily located between 0 and −20 layer in all the six cases.Ice crystals mainly form above the level of −20 and even appear above the level of −40 within strong convective clouds.Rainwater mostly appears below the melting layer,indicating that its formation mainly depends on the melting process of precipitable ice particles.Snow and graupel particles have the characteristics of high content and deep vertical distribution,showing that the ice phase process is very active in the development of clouds and precipitation.The conversion and formation of hydrometeors and precipitation over the plateau exhibit obvious characteristics.Surface precipitation is mainly formed by the melting of graupel particles.Although the warm cloud microphysical process has less direct contribution to the formation of surface precipitation,it is important for the formation of supercooled raindrops,which are essential for the formation of graupel embryos through heterogeneous freezing process.The growth of graupel particles mainly relies on the riming process with supercooled cloud water and aggregation of snow particles.(Tang Jie,Guo Xueliang,Chang Yi)

1.4 Comparative analyses of vertical structure of deep convective clouds with multi-source satellite and ground-based radar observational data at Naqu over the Tibetan Plateau

In order to improve the understanding of deep convective clouds over the Tibetan Plateau,the characteristics of vertical structures of a deep strong convective cloud over Naqu Station and a deep weak convective cloud about 100 km to the west of Naqu station occurred during 13:00−16:00 BT 9 July 2014 in the Third Tibetan Plateau Atmospheric Science Experiment are analyzed based on multi-source satellite data from TRMM,CloudSat and Aqua and radar data from ground-based vertically pointing radars (C-band frequencymodulated continuous-wave radar and KA-band millimeter wave cloud radar).The results are as follows:(1) The horizontal scales of the deep strong convective cloud and deep weak convective cloud both were small (10−20 km),and the tops were high (15−16 km above the sea level,the same hereafter).Across the level of the 0 isotherm,the reflectivity increased rapidly,suggesting that the melting process of solid precipitation particles through the 0 level in the deep strong convective cloud played an important role.A bright band located at 5.5 km (1 km AGL) appeared during the period of convection weakening.(2) The reflectivities from TRMM precipitation radar below 11 km were found to be overestimated compared to those derived from the C-band frequency-modulated continuous-wave radar.(3) Deep convective clouds were mainly ice clouds,and there were rich small ice particles above 10 km,while few large ice particles were found below 10 km.The microphysical processes of the deep strong convective cloud and the deep weak convective cloud mainly included mixed-phase process and glaciated process,and the mixed-phase process can be divided into two types:one was the rimming process below the level of −25 (deep strong convective cloud) or −29 (deep weak convective cloud) and the other one was aggregation and deposition process above the level.The latter process was accompanied with fast increase of ice particles effective radius.These evidences from space-based and ground-based observational data further clarify the characteristics of vertical structure of deep convective clouds over the Tibetan Plateau,and provide a basis for the evaluation of simulation results of deep convective clouds by cloud models.(Wang Hui,Guo Xueliang)

1.5 Measurements of natural ice nucleating particles in Beijing in the spring of 2017

The ice nucleating particles (INPs) in the ambient air in Beijing during the spring of 2017 were observed using an improved 5-L version of the Bigg’s mixing cloud chamber.The characteristics of the diurnal INPs concentrations are analyzed and compared with measurements made in 1963,1995 and 1996.The particle number size distribution was also measured simultaneously.The correlation between the concentration of INPs and the aerosol number concentration in different size ranges is discussed.Moreover,the relationship between the concentration of INPs and different meteorological factors,such as wind speed,air pressure,temperature,humidity and weather conditions,are analyzed.From the results of observation,in general,the concentrations of INPs at −20 ,−25 and −30 temperatures trend with each other on a day to day basis,although there are slight differences in some cases at −20 .As the activation temperatures decrease by 5 ,the concentration of INPs increases by about one order of magnitude.The concentration of INPs increases significantly when air pollution is severe,but the specific relationship between INPs and pollution needed to be verified in the follow-up work,which is related to the sources of pollution and the aerosol components.Compared with historical experimental data,interpreting trends using short sampling periods in individual years over decadal time frames,the average concentrations of INPs in Beijing increased by approximately 15 times from 1963 to 1996,but in the past 20 years,the concentration of INPs has decreased significantly.For aerosols with particle size that exceeds 0.5 μm,the correlation coefficient between aerosol number concentration and INPs increases significantly with increasing aerosol particle size; however,it tends to stabilize at approximately 0.6 for aerosol particles larger than approximately 2 μm.A comparison with meteorological parameters shows that the concentration of INPs is inversely correlated with wind speed,and displays a positive correlation with relative humidity.These results indicate that conditions that favor dispersion lead to reduced concentrations of INPs.(Che Yunfei,Dang Juan,Fang Wen,Shen Xiaojing,Sun Junying,Chen Yue,Qian Yao)

1.6 Toward understanding the process-level impacts of aerosols on microphysical properties of a shallow cumulus cloud using aircraft observations

Representation of clouds remains as the largest uncertainty in future climate predictions.Numerous studies have found and investigated the impacts of aerosols on cloud microphysical properties.However,few studies have investigated the process-level impact of aerosols on cloud microphysical properties,particularly over heavy polluted the North China Plain region.Using the aircraft observations,this study investigates the variation of cloud droplet size distribution (DSD) with aerosol concentration and vertical velocity (VV) in a shallow cumulus cloud with sufficient liquid water content (LWC).Strong variation in both cloud droplet number concentration (N) and LWC exists,with values from a few cm−3to＞1200 cm−3,and from 0 to 3.0 g/m3,respectively.In general,the total cloudN(effective radiusre) for cases with weak VV is slightly less (smaller) than that for cases with high VV for this cumulus cloud with high LWC.Potential mechanisms about the impacts of aerosols (or VV) on the cumulus microphysical properties are proposed for both high and low LWC conditions.Simply said,the change of cloudNmainly depends on the amount of aerosols,and the change of cloud dropletredepends on both the supply of water content and the amount of aerosols:if LWC is high and aerosol amount is not too large,both cloudNandreincrease with increasing aerosols; if LWC is low or if LWC is high but aerosol amount is too large,cloudNincrease butredecrease with increasing aerosols.Note that for two cases with very strong downdraft,the cloud droplets seem less and smaller than strong VV cases.The most likely reason is that very strong downdraft along with the adiabatic cooling makes dry air above the cloud enter into clouds and causes evaporation of droplets,resulting in smaller and less cloud droplets.(Yang Yang,Zhao Chuanfeng,Dong Xiaobo)

1.7 Evaluation of hygroscopic cloud seeding in liquid-water clouds:A feasibility study

An airborne cloud seeding experiment was conducted over the eastern coast of Zhejiang,China,on 4 September 2016 during a major international event held in Hangzhou.In an attempt to reduce the likelihood of rainfall onset,a major airborne experiment for weather modification took place by seeding hygroscopic agents to warm clouds to reduce cloud droplet size.The effectiveness of seeding is examined,mainly for stratiform clouds with patchy small convective cells.A radar-domain-index (RDI) algorithm was proposed to analyze the seeding effect.The threshold strategy and the tracking radar echo by correlation (TREC) technique was applied in the domain selection.Factors analyzed include echo reflectivity parameters such as the mean and maximum echo intensity,the anomaly percentage of the grid number of effective echoes,the fractional contribution to the total reflectivities,and the vertically integrated liquid (VIL) water content during and after the seeding process.About 12 min after seeding ended,the composite reflectivity of seeded clouds decreased to a minimum (＜10 dBz) and the VIL of seeded clouds was 0.2 kg m−3.The echo topheight dropped to 3.5 km,and the surface echoes were also weakened.By contrast,there was no significant variation in these echo parameters for the surrounding nonseeded clouds.The seeded cell appeared to have the shortest life cycle,as revealed by applying the cloud-cluster tracking method.The airborne Cloud Droplet Probe (CDP) measured the cloud number concentration,effective diameter,and liquid water content,which gradually increased after the start of cloud seeding.This is probably caused by the hygroscopic growth of agent particles and collision-coalescence of small cloud droplets.However,these parameters sampled at 40 min after seeding decreased significantly,which is probably due to the excessive seeding agents generating a competition for cloud water and thus suppressing cloud development and precipitation.Overall,the physical phenomenon was captured in this study,but a more quantitative in-depth analysis of the underlying principle is needed.(Wang Fei,Li Zhanqing,Jiang Qi,Wang Gaili,Jia Shuo,Duan Jing,Zhou Yuquan)

1.8 Observation study of aerosol spectrum and meteorological conditions under dust weather in Nanjing

In this paper,the characteristics of aerosol spectrum and meteorological conditions of a dust storm were analyzed on May 2011.To compare with different weather background,another 3 days of aerosol properties were discussed.The results showed that the dust storm was originated in the southern Mongolia and central Inner Mongolia,influenced Nanjing through Beijing and Shandong from the direction of southeast.The local pollution was serious before the dust intrusion and the ultrafine particles mainly ≤0.08 μm.The coarse particles≥0.5 μm mainly occurred during and after the dust intrusion.Compared with other pollution and clean days in the same season,the aerosol concentration affected by dust storm and local pollution was five times higher than that in the clean days in Nanjing.By the influence of local pollution,the diurnal variation of aerosol showed double peaks which located at about 10:00 and 20:00,respectively.Dust and precipitation had great influence on aerosol diurnal variation.The dry and wet removal processes affected the time of the aerosol concentration peaks.(Wang Fei,Jiang Qi,Zhu Bin)

1.9 Below-cloud aerosol scavenging by different rain intensities in Beijing

Below-cloud aerosol scavenging process by precipitation is an important mechanism for cleaning the polluted aerosols in atmosphere,and is also a main process for acid rain formation.However,the physical mechanism has not been well clarified yet due to complex precipitation processes.We investigated the belowcloud PM2.5(particulate matter with aerodynamic diameter is 2.5 μm and less) scavenging ratio by different rain intensities in the pollutant condition characterized by high PM2.5concentration based on measurements from March 2014 to July 2016 in Beijing.It was found that relatively more intense rain event was more efficient in removing the polluted aerosols in atmosphere.The mean PM2.5scavenging ratio and its standard deviation (SD) were 5.1±25.7%,38.5±29.0% and 50.6±21.2% for light,moderate and heavy rain events,respectively.We further found that the important impact factors on the below-cloud PM2.5scavenging ratio for light rain events were rain duration and wind speed rather than raindrop size distribution.However,the impacts of rain duration and wind speed on scavenging ratio were not important for moderate and heavy rain intensity events.To our knowledge,it is the first statistical result about the effect of the raindrop size distribution on below-cloud scavenging in China.(Luan Tian,Guo Xueliang,Zhang Tianhang,Guo Lijun)

1.10 Effects of convection over the Tibetan Plateau on rainstorms downstream of the Yangtze River Basin

This study investigated the effect of convection over the Naqu region of the central Tibetan Plateau (TP) on rainstorms in the downstream areas of the Yangtze River Basin (YRB) accompanied by water vapor transport during August 15–19,2014.The hourly maximum C-band frequency-modulated continuous-wave (C-FMCW) radar echo intensity at Naqu obtained from the Third Tibetan Plateau Atmospheric Scientific Experiment (TIPEXIII) was applied to represent local convective motion during this rainstorm process.Results based on hourly raingauge station data,National Centers for Environmental Prediction (NCEP) Final (FNL) Operational Global Analysis data,and Weather Research and Forecasting (WRF) simulations revealed that convection at Naqu was a strong signal over the TP.Convection over the Naqu region could impact rainstorms in the middle and lower reaches of the YRB via a three-dimensional water vapor flux vortex (WVFV) structure with high-level divergence and low-level convergence.The eastward propagation of the WVFV structure would enhance convection and thereby develop rainstorms downstream of the YRB.A FLEXible PARTicle (FLEXPART) dispersion model tracked the trajectory of air masses originating from the TP toward the middlelower reaches of the YRB,which supported the robustness of the diagnostic results.(Zhao Yang,Xu Xiangde,Liu Liping,Zhang Rong,Xu Hongxiong,Wang Yinjun,Li Jiao)

1.11 The large-scale circulation patterns responsible for extreme precipitation over the North China Plain in midsummer

Extreme precipitation events over the North China Plain (NCP) in midsummer during 1979–2016 are classified into two types using objective cluster analysis:a northern pattern with heavy precipitation and a central-southern pattern with relatively moderate precipitation.The large-scale circulation patterns responsible for the midsummer extreme precipitation are then determined.In the northern NCP type,extreme precipitation accompanies a zonal gradient between an anomalous low-pressure system at high latitudes and the westward- and northward-extended western North Pacific subtropical high (WNPSH).Anomalous southwesterlies flow is driven by a trough that extended from the high latitudes to the northern NCP,where it encounters southeasterly wind flow induced by an anomalously northward-extended WNPSH and a southern low-pressure anomaly at low latitudes.Anomalous amounts of moisture are mainly transported from the tropical western Pacific by southeasterlies.In the central-southern NCP type,remarkable anomalous low-pressure systems control all of the northern China with centers over the Sichuan Basin and Northeast China.The westward-extended WNPSH occupies further south than that of the northern NCP type.The southwesterly low-level jet (LLJ) is more prevalent in the central-southern NCP type than in the northern NCP type.This southwesterly LLJ plays an important role in extreme precipitation over the central-southern NCP by transporting moisture primarily from the Bay of Bengal and the South China Sea and generating convergence.In addition,the upper-level anomalous strong divergence that is anchored over the right entrance of the westerly jet makes a greater contribution to extreme precipitation in the northern type than in the central-southern type.(Zhao Yang,Xu Xiangde,Li Jiao,Zhang Rong,Kang Yanzhen,Huang Wubin,Xia Yu,Liu Di,Sun Xiaoyun)

1.12 Analysis of chemical composition,sources and process characteristics of submicron aerosol in the summer of Beijing,China

In this study,aerosol chemical speciation monitor (ACSM) and various collocated instruments are used to observe and analyze the chemical compositions,source and extinction characteristics of submicron aerosol (PM1,aerodynamic diameter less than 1 μm) in Beijing from July to September,2012.The results show that the average mass concentration of PM1during the whole observation period is 53.8 μg m−3,accounting for 70%−85% of PM2.5on average.From July to September,the average mass concentration of non-refractory submicron aerosol (NR-PM1) declines monthly with the increasing fraction of OA in NR-PM1.The organics aerosol (OA) contributes the major mass fraction of PM1during the cleaning days,and the fraction of inorganics shows a significant increasing trend with the accumulation of pollutants.The effects of meteorology on PM pollution and aerosol processing are also explored.In particular,SOR increase significantly at elevated relative humidity (RH) periods which suggested that the conversion of SO2to SO42−in pollution episodes is more effective through the aqueous-phase oxidation of SO2instead of the gas-phase oxidation.In addition,the effect of wind speed on the primary species (PPM) is significantly weaker than that on the secondary species (SPM).In addition,the mass concentration of SPM (or organics) is more sensitive to wind speed changes,compared with PPM (or inorganics).The proportion of oxygenated OA (OOA) in OA is significantly higher than that of hydrocarbon-like OA (HOA),and as the proportion of OA in PM1 increases,the mass fraction of OOA in OA decreases gradually.Moreover,the particulate matter (PM) in Beijing shows essentially neutral during the observation period.The total extinction coefficient of PM tracks well with the PM1(r2=0.72),and the extinction efficiency of the secondary particulate matter (SPM) (r2=0.92) is significantly higher than that of the primary particulate matter (PPM) (r2=0.58).Meanwhile,the correlation between OA and extinction coefficient (r2=0.56) is weaker than that between inorganics and extinction coefficient (r2=0.86).(Jiang Qi,Wang Fei,Sun Yele)

1.13 1961—2015年中国地区冰雹持续时间的时空分布特征及影响因子研究

利用1961—2015年中国地区577个地面观测站的冰雹资料，应用统计学方法，分析了冰雹持续时间的空间分布、年际变化以及日变化特征，包括站点降雹累积持续时间、平均单次降雹持续时间、区域平均单次降雹持续时间、小时降雹累积持续时间和总降雹累积持续时间。结果表明：（1）1961—2015年中国地区站点降雹累积持续时间与海拔高度呈现较高的正相关关系，相关系数高达0.99。站点降雹累积持续时间的最大值出现在青藏高原地区，累积持续时间高达250 min，其次为内蒙古中部以及东北部的山区地带，累积持续时间约为150 min。（2）1961—2015年平均单次降雹持续时间呈现上升趋势，55年冰雹累积持续时间大约增长1 min，且通过了95%信度水平的显著性检验。（3）西北地区、北部平原地区和东南地区在1961—1980年期间，区域平均单次降雹持续时间都有显著的下降趋势，而在1970—2015年期间西北地区和青藏高原地区呈现显著的上升趋势。1961—1980年期间区域平均单次降雹持续时间在西北地区的长期趋势变化主要受到日最低气温以及温度日较差长期年际变化的影响，在北部平原地区仅与温度日较差相关，而在东南地区与3个对流参数都有较好的相关性；1970—2015年和1961—2015年期间西北地区和青藏高原地区的区域平均单次降雹持续时间的上升趋势分别与这两个区域的区域平均日最高气温、日最低气温呈正相关。（4）单次降雹持续时间的日变化明显，午后至夜间出现的冰雹持续时间长于凌晨和上午的冰雹过程，持续时间峰值出现在当地时间17：00和18：00。本文还利用探空资料分析了对流有效势能和Totals-totals指数与冰雹持续时间的关系，结果表明中国地区20：00（北京时）的对流有效势能和Totals-totals指数可能是冰雹持续时间日变化的影响因子之一。（赵文慧，姚展予，贾烁，王伟健，张沛，高亮书）

1.14 六盘山区夏秋季大气水汽和液态水特征初步分析

六盘山区是中国典型的农牧交错带和生态脆弱带，也是黄土高原重要的水源涵养地、生态保护区及国家级扶贫开发区。利用2017年6—11月隆德气象站地基多通道微波辐射计资料，结合同期平凉探空站及隆德地面降水等观测资料，分析了六盘山区夏秋季大气水汽、液态水变化特征。结果表明：六盘山区夏秋季在降水天气背景下，大气水汽含量和液态水含量均较高，分别为无降水天气背景下的14倍和70倍；降水天气背景下水汽在5000m以下有明显的增加，且在此高度范围内的水汽密度随高度的递减率比无降水天气背景下明显偏小；各高度层的液态水相比无降水天气背景下均有明显增大，除6月外，主峰值均出现在0 ℃层高度层以下。六盘山区夏秋季各月中，6—9月大气水汽含量高值区均出现在正午到傍晚时段，低值区均出现在日出前后；液态水含量在日出前、午后及傍晚分别出现峰值，最明显的峰值出现在午后。对一次对流性降水天气过程分析后发现，降水发生前40 min大气水汽含量和液态水含量出现两次明显的跃增，水汽向上输送不断加强，2500～7500 m高度的相对湿度明显增大。（田磊，桑建人，姚展予，常倬林，单新兰，曹宁，孙艳桥）

1.15 基于航测的珠三角气溶胶垂直分布及活化特性

2017年9月14—27日，在珠三角地区开展了6个架次飞机观测试验。利用飞行获取的气溶胶、云凝结核、云滴及常规气象探头资料，结合天气形势、气象条件及气团后向轨迹分析，研究了珠江三角洲深圳地区气溶胶数浓度及其谱的垂直分布特征，配合不同过饱和度条件下云凝结核浓度观测，分析了气溶胶活化特性。结果表明：在不同天气条件下，深圳低层气溶胶数浓度变化范围为500～9000 cm-3；边界层内气溶胶分布相对均匀，谱型随高度变化与气象条件相关。将6架次气溶胶根据数浓度及谱型分为3种类型：类型Ⅰ为海洋型气溶胶，数浓度小，粒子尺度大，谱型呈双峰分布；类型Ⅲ为大陆型气溶胶，数浓度高，粒子尺度小，谱宽较宽且呈三峰分布；类型Ⅱ为海洋大陆影响型气溶胶，即受海洋和大陆共同影响，数浓度低于类型Ⅲ高于类型Ⅰ，谱型为双峰分布。拟合了包含海洋型及大陆型气溶胶的3架次近地面云凝结核活化谱，计算了气溶胶在不同过饱和度条件下的活化效率。（段婧，楼小凤，陈勇，高扬，李霞，周荣斌，毛辉，卢广献，汪会，林俊君）

1.16 安庆地区一次飞机积冰的气象条件分析

利用卫星、雷达、探空、飞机等观测资料和NCEP 再分析资料，以及数值模拟结果，对2016年3月8—9日我国安庆地区的云系特征和飞机积冰气象条件进行了分析，并对比了几种积冰指数算法的计算结果。结果表明，此次飞机积冰发生在寒潮天气背景下，强冷空气造成锋面逆温。实测飞机积冰现象出现在对流降雨结束后的层积云层顶部，积冰高度对应高空锋区逆温层底部，云顶高度约3.4 km，云顶温度-10 ℃，无降水和雷达回波，云中主要为过冷水，丰沛时段飞机观测过冷水平均值为0.36 g/m3，基本无冰相粒子。当云顶高度再度抬升，冰相粒子增多时，过冷水含量减少，不利于积冰现象发生。多种积冰指数对比分析表明，CIP初始积冰潜势算法较好体现了此次层积云飞机积冰特征。CPEFS模式模拟出了与实测比较一致的云宏微观结构。（孙晶，蔡淼，王飞，史月琴）

1.17 华南一次强对流天气过程中环境条件对MCS形态特征的影响

2014年5月22日华南地区出现了一次大范围强对流天气过程，该过程中出现了2个中尺度对流系统（MCS）MCS-A和MCS-B，2个MCS表现出迥异的形态特征，产生了不同的强对流天气。本研究利用多源观测资料以及高分辨率数值模式分析了环境条件对于MCS形态特征的影响。结果表明：（1）广西夜间到凌晨边界层顶附近强盛的低空急流，使得MCS-A在北部山区出现后向建立（BB）的形态特征，有利于大量级的短时强降水的出现。（2）MCS-A进入广西平原地区以后，强盛的边界层以上的低空急流使得能量垂直廓线的极大值在边界层高度以上，且风垂直切变特征不利于冷池前方的垂直运动发展，冷池前方无法连续触发对流，MCS-A逐渐演化成线状对流/层云伴随（TL/AS）的形态特征，而后消亡。（3）在广东，能量极大值出现在大气底层，环境风廓线有利于冷池前方垂直运动发展，进而触发新的对流，新生成的MCS-B呈现典型的层云拖曳型（TS）形态，最终形成飑线，造成雷暴大风天气。（胡宁，汪会）

1.18 利用微雨雷达研究一次冷锋云系降水的垂直结构分布及演变特征

利用河北邢台测站 Ka波段微雨雷达（MRR）观测到的一次冷锋云系降水过程分析降水的垂直分布及演变特征。将 MRR观测结果与天气雷达、地面雨滴谱仪、雨量计观测结果进行对比以检验 MRR数据的可靠性。同时将 MRR与雨滴谱仪和激光云高仪结合，研究了不同相对湿度阶段特征量、雨滴谱的平均垂直分布特征和降水特征量随时间、高度的演变特征。结果表明：MRR与雨量计及雨滴谱仪累计雨量结果较为接近，趋势一致。MRR 200 m雨强值与地面雨滴谱仪雨强值偏差最小，平均偏差为 0.05 mm/h，相关系数为 0.93。相比雨滴谱仪，MRR观测到的小滴数浓度出现高估，大滴数浓度出现低估，中滴数浓度较为一致。降水在云内和云外受不同微物理过程影响，垂直变化特征不同。降水初期平均反射率和雨强在云底以下明显减小，小滴和中滴平均数浓度明显减小，蒸发作用影响较强。而在其余时间段在云内随高度降低平均反射率和雨强略有增加，小滴平均数浓度变化较小，中滴大滴平均数浓度增加，表明云内有云滴与雨滴间的碰并发生。而在云外低层，随高度降低平均有效直径明显增加，平均雨滴总数浓度明显减小，小滴平均数浓度显著减小，大滴平均数浓度显著增加，表明在云外低层雨滴间的碰并作用较强。（崔云扬，周毓荃，蔡淼）

1.19 雨滴谱垂直演变特征的微雨雷达观测研究

雨滴谱的垂直变化特征对于认识降水过程、改进模式和雷达定量估计降水等具有重要意义。利用2016年6月1日至9月30日雨量筒、微雨雷达（MRR）和PARSIVEL 雨滴谱仪连续4 个月的观测数据，在对比3 种仪器观测结果的基础上，研究了层状云降水不同降水强度下微物理特征量和雨滴谱垂直演变特征。结果表明：MRR 与PARSIVEL 雨滴谱仪观测降水强度相关性较好，且两种仪器观测的雨滴谱在中等粒子段（0.5～2.5 mm）表现出较好的一致性，而对于小粒子段（雨滴直径小于0.5 mm）PARSIVE雨滴谱仪观测的数浓度明显低于MRR。对于弱降水（降水强度R＜0.2 mm/h），液水含量和降水强度随高度降低减小，雨滴在下落过程中蒸发明显。对于较强降水（R＞2 mm/h），随高度降低，雷达反射率因子増大，小滴数浓度减小的同时大滴数浓度増加明显，雨滴下落过程碰并作用明显。所有高度直径不超过0.5 mm 的小滴对数浓度贡献均为最大。高层雨滴直径不小于1 mm的小粒子对降水强度的贡献可达50%，小粒子对降水强度贡献随高度降低而减小。（宋灿，周毓荃，吴志会）

1.20 一次冰雹天气过程的云系发展演变及云物理特征研究

利用中尺度数值模式WRF的数值模拟，结合 NCEP/FNL再分析资料、地面、探空、多普勒雷达基数据和卫星产品等观测资料，综合分析了2014年3月30日发生在贵州省西南部的一次冰雹天气过程。研究了有利于冰雹发生的环流特征和环境条件，分析了冰雹云系的发展演变特征、云微物理结构特征，初步分析了冰雹形成的云物理机制。结果表明：此次冰雹天气是典型的低压辐合线型降雹类型，地面降雹位置位于700 hPa切变线和近地面辐合线附近及南侧；发生此次冰雹过程的对流云系经历了对流云系的初生阶段、合并加强阶段、成熟降雹阶段和东移阶段。贵州地区上空对流云系的微物理结构具有混合相云特征，高层为冰晶、雪，中层为云水、霰，低层为雨水、冰雹。霰和云水是形成雨水和冰雹的主要来源，霰撞冻过冷云水和霰的自动转化是冰雹形成的主要微物理机制。（张小娟，陶玥，刘国强，彭宇翔）

1.21 云辐射效应在华北持续性大雾维持和发展中的作用

观测研究发现华北地区的持续性大雾天气通常伴随高层云的存在，具有云-雾共存结构特征，为揭示云在持续性大雾维持和发展中的作用，本文利用中尺度数值模式WRF，结合华北雾霾观测试验期间的卫星、探空、地面观测、系留汽艇、微波辐射计等观测资料，研究了2011年12月3—6日和2013年1月28—31日两次华北持续性大雾天气形成和发展演变过程。在模拟与观测对比检验研究的基础上，重点开展了云辐射效应在大雾维持和发展中的作用。研究结果表明：两次大雾过程持续时间长达48 h以上，近地面具有偏南暖湿平流，在持续性大雾发展过程中，均出现了由单层雾发展为云—雾共存结构，一般是雾形成24 h以后有中高云移到雾层之上，云底高度在3 km以上，云厚超过3.5 km，云中以冰晶和雪晶为主。白天云—雾共存结构出现后，云—雾的反照率效应使地表接收的短波辐射减少了71%～84%，地面增温效应显著减小，从而阻碍了大雾的消散过程，使大雾天气得以维持，同时由于云—雾产生的温室效应，湍流过程加强，使地面雾向上扩展，雾在稳定层内维持；夜晚云—雾共存时，由于云—雾温室效应使地表净长波辐射增加了70 W/m2以上，导致地面长波辐射冷却过程减弱，并不利于雾的加强，但云对雾的增温效应有利于混合层内的湍流扩散过程，促使雾在更高的空间内得以维持。可见，在云—雾共存结构中，云辐射效应有利于低层大雾的长时间维持，对持续性大雾的形成和发展产生了重要作用。（郭丽君，郭学良，栾天，吕恺）

1.22 庐山云雾及降水的日、季节变化及宏微观物理特征观测研究

庐山云雾观测站2015年重新开始观测试验。利用2015年11月至2018年2月庐山云雾试验站观测的云物理资料和九江站的雷达资料，统计研究了庐山云雾及降水的日、季节变化和宏微观物理特征。研究结果表明，庐山强降水多发生在夏季，降水强度超过100 mm/h，而云雾天多发生在秋冬春季，最高云和雾天数高达25天/月，最低能见度可达到20 m，东北风有利于水汽的冷却凝结。云雾辐射影响下的日最低温度发生在09：00左右，即云雾消散前。利用雷达资料对降水分类，庐山秋冬季层状云、积层混合云和对流云降水分别占29%、44%和27%，春夏季对流云和积层混合云降水分别占83%和17%。和城市降水和雾相比，庐山降水的中小雨滴偏多，云雾滴谱的数浓度较低，双峰结构显著，且谱较宽。随着云内降水量级的增加，雨滴的数浓度和尺度不断增加，更易于启动碰并机制，使小于11 μm和大于30 μm云雾滴减少，导致11 μm的峰值更为显著。降雪期间的小云雾滴较为丰富，固态降水更容易通过淞附过程消耗大的过冷云滴。（郭丽君，郭学良，楼小凤，卢广献，吕恺，孙赫敏，李军，张小鹏）

1.23 华北一次浓雾过程爆发性增强的微物理特征

基于华北雾—霾综合观测试验资料，分析了2011年12月4日河北涿州一次浓雾过程爆发性增强的微物理特征及形成机理。结果表明：本次浓雾过程除具有均压场、地面辐射降温、逆温层、静稳天气等特征外，还具有雾微物理过程出现爆发性增强的特征，10 min内，小雾滴浓度显著增加，含水量增大了3个量级，雾滴谱由15 μm拓宽到35 μm，能见度由500 m骤降至70 m。夜间地面长波辐射冷却效应导致近地层雾的形成，而近地层雾的形成反过来快速地增强了地面长波辐射冷却效应，促使大量小雾滴的形成和碰并过程的产生，这是一种正反馈效应；大量雾滴形成释放的潜热，促使雾体抬升和向下长波辐射增强，又使地面长波辐射冷却效应减弱，这是一种负反馈效应。相对于南京辐射雾过程，本次华北浓雾的小雾滴粒子数浓度高，液水含量明显偏小，这与华北高浓度气溶胶和弱水汽输送有关。（方春刚，郭学良）

1.24 京津冀一次罕见的双雨带暴雨过程成因分析

2013年7月1日京津冀区域在副热带高压北抬、 偏南低空急流加强、 高空槽东移的环流背景下，出现了一次罕见的降水强度大、 持续时间长的双雨带暴雨过程。利用常规观测、NCEP （National Centers for Environmental Prediction）再分析资料和多种加密观测以及雷达变分同化分析资料等对此次暴雨过程的成因和中尺度特征进行了分析。结果表明：南北两支暴雨带的形成机制和中尺度过程有显著差异，但是双雨带在形成与维持过程中也有相互促进作用。南支暴雨带发生于西南暖湿气流加强的环境下，对流不稳定层结显著、整层湿度大；强降水是在暖式中尺度辐合线的触发和组织下由中尺度对流复合体产生的，雷达回波具有明显的“列车效应”和后向传播特征，属于深厚的暖区湿对流暴雨，雨强和累积雨量极大、中尺度特征明显；地面辐合线及中尺度涡旋的位置决定了雨带和特大暴雨中心的位置，强降水产生的冷池出流和偏南暖湿气流形成的温度梯度最大区域指示了强回波的传播方向。北支暴雨带是在冷式切变线和低空低涡的影响下，由切变线云系形成的多单体回波带造成的；不稳定能量条件比南支暴雨带差，但是高低空系统耦合作用产生的上升运动强，中层的干冷侵入形成了明显的θse锋区，属于锋面对流系统，同时地形对降水有显著的增幅作用，多种因素综合作用造成雨强相对较弱，但是降水持续时间长，暴雨区面积大；过程中低空低涡的移动路径与强降水的落区和雨带的位置有较好的对应。南支暴雨带暖区降水后边界层形成的偏东风不仅为北支暴雨带提供水汽输送，而且在太行山前的地形抬升作用促使了强对流单体的发生发展，增强了北支暴雨带的降水强度，而太行山前强对流降水造成的冷池促进了地面中尺度涡旋的形成，造成南支暴雨带后期强对流回波的合并和降水的再度加强。（王华，李宏宇，仲跻芹，吴进，李梓铭，吴剑坤）

1.25 2016年冬季京津冀豫大气污染的时空分布及影响因子研究

利用2016年12月至2017年2月北京、天津、石家庄和郑州的PM2.5质量浓度、反应性气体质量浓度及其相对应的气象要素资料分析了大气污染的理化特征、传输和生消规律。结果表明：北京、石家庄、天津及郑州的PM2.5质量浓度分布频率均有两个较为明显的峰值，4个地区PM2.5质量浓度分布频率最高时均值分别为10.1、19.2、40.0和47.1 μmg/m3，大气的氧化程度为北京最低，其次为石家庄、天津，郑州最高。4个研究地区的交通源对环境大气污染均有重要贡献。PM2.5和CO的相关性在低相对湿度时高于高相对湿度时；而PM2.5和NO2的相关性在相对湿度较大时高于相对湿度较小时。4个研究地区的PM2.5质量浓度均随风速的增大呈快速降低后趋于平缓的趋势，其中北京、石家庄和郑州的风速阈值均为3 m/s，天津地区为4 m/s。受上游污染地区的影响，偏南风的输送作用滞后20～30 h达到最大，而偏北风的影响作用在滞后8～12 h 达到最大。（江琪，王飞，张恒德，吕梦瑶，何佳宝）

1.26 不同降水强度对PM2.5的清除作用及影响因素分析

云和降水过程是大气污染物的重要清除途径，但由于降水过程和大气污染颗粒物本身的复杂性，目前降水过程对大气污染物的清除机制及影响因素有待深入研究。本文利用2014年3月至2016年7月在北京地区连续观测的PM2.5和降水数据，研究了不同降水强度对PM2.5的清除率，以及雨滴谱、风速和降水持续时间对PM2.5清除率的影响。研究表明，降水强度越大，对PM2.5的清除效率越高。小雨、中雨和大雨对PM2.5清除率的平均值分别为5.1%、38.5%和50.6%。小雨不但对PM2.5的清除率最低，而且对PM2.5的清除效果也存在很大差异，约50%的小雨个例中PM2.5质量浓度出现减小情况，而另外50%的小雨个例中，PM2.5质量浓度有增加现象。在持续时间长或地面风速增大的情况下，小雨也表现出较高的清除率。在中雨和大雨情况下，PM2.5质量浓度均出现明显减小情况。但降水持续时间和风速对中雨和大雨的清除率影响较小，这是由于中雨和大雨一般在较短时间内就可以清除大部分PM2.5，因此对降水的持续时间和风速大小影响不敏感。（栾天，郭学良，张天航，郭丽君）

1.27 一次浙江对流云人工催化数值模拟试验

为了研究吸湿性催化剂、碘化银催化剂及两者的联合催化效果，本文利用双参数三维对流云催化模式，对南方一次对流云降水过程分别进行盐粉暖云催化、碘化银冷云催化和冷暖混合催化试验，对比研究不同催化方案对对流云降水的可能影响。结果表明盐粉催化导致先增雨后减雨，主要通过盐溶滴与云滴碰并增长，及雨滴碰并和霰粒子碰冻过程消耗。在上升气流区和降水前期进行催化的增雨效果更好；30 µm粒径的盐粉催化剂量为12.5/L时，可增加降水量17.8%。在降雨过程的不同发展阶段进行AgI催化，表现出先减雨后增雨的催化效果。盐粉和碘化银的联合催化，两者催化效果的不同步，使得不同吸湿性催化剂和碘化银催化剂量配置会导致不同的催化效果。当30 μm的盐粉催化剂量为12.5/L、联合碘化银100/L的冷区催化时，可以取得19%的增雨效果。（楼小凤，傅瑜，孙晶）

1.28 吸湿性播撒对暖性对流云减雨影响的数值模拟

利用以色列特拉维夫大学二维面对称分档云模式，对2016年9月4日16：00（北京时）前后我国华东地区的一次暖性浅对流云降水过程进行模拟，模式模拟的强回波中心高度和最大回波强度范围与观测基本一致。并在此基础上进行了小于1 μm 的吸湿性核的播撒减雨试验，分别考虑了不同播撒时间、不同播撒高度以及不同播撒剂量的敏感性测试。结果表明：在云的发展阶段早期播撒能起到更好的减雨效果，播撒时间越早对大粒子生长过程的抑制作用越强，随着播撒时间向后推移，受抑制作用最显著的粒径段向小粒径端偏移；在云中心过饱和度大的区域下方进行播撒，减雨效果更加明显，当播撒剂量为350 cm−3时，地面累积降水量减少率可达23.3%；另外，随着播撒剂量的增加，减雨效果更加显著，甚至能达到消雨的效果。因此，在暖性浅对流云中合理地播撒小于1 μm 的吸湿性核能达到较好的减雨或消雨效果。（刘佩，银燕，陈倩，楼小凤）

1.29 云雾物理膨胀云室研制及参数测试

膨胀云室可以形成水汽水面和冰面过饱和环境，是研究气溶胶粒子、人工影响天气冷暖催化剂核化过程和机理的重要设备，但长期以来我国缺乏配套先进云雾粒子谱和图像测量系统的膨胀云室。本文介绍了我国自主研制的膨胀云室系统，由云室主体、环境和云雾测量系统、通信系统和控制系统4个子系统组成。该系统首次采用了国产云粒子谱仪和成像仪测量系统。测试试验表明，该云室具有良好的温度和压力控制能力，平均降温速率达到0.25 ℃/min，温度分布均匀、−40 ℃时温差小于0.29 ℃；膨胀造雾过程4 min，雾可维持4 min，雾滴较小；可以实现从常温到−52 ℃低温环境的控制、压力膨胀成云雾模拟和微物理参数监测能力，解决了我国长期缺乏气溶胶粒子和暖云催化剂室内实验装备的状况，对于验证暖云催化剂核化性能和提高暖云人工增雨科技水平具有重要价值。（苏正军，郭学良，诸葛杰，王平）

2 关键技术研发与业务应用转化

2 Key technology development and application

2.1 An improvement of the retrieval of temperature and relative humidity profiles from a combination of active and passive remote sensing

This paper focuses on an improvement of the retrieval of atmospheric temperature and relative humidity profiles through combining active and passive remote sensing.The ground-based microwave radiometer and millimeter-wavelength cloud radar were used to acquire the observations.Cloud base height and cloud thickness determinations from cloud radar were added into the atmospheric profile retrieval process,and a back-propagation neural network method was used as the retrieval tool.Because a substantial amount of data is required to train a neural network,and as microwave radiometer data are insufficient for this purpose,eight years of radiosonde data from Beijing were used as the database.The monochromatic radiative transfer model was used to calculate the brightness temperatures in the same channels as the microwave radiometer.Parts of the cloud base heights and cloud thicknesses in the training dataset were also estimated using the radiosonde data.The accuracy of the results was analyzed through a comparison with L-band sounding radar data and quantified using the mean bias,root-mean-square error and correlation coefficient.The statistical results showed that an inversion with cloud information was the optimal method.Compared with the inversion profiles without cloud information,the RMSE values after adding cloud information were reduced to varying degrees for the vast majority of height layers.These reductions were particularly clear in layers with clouds.The maximum reduction in the RMSE for the temperature profile was 2.2 K,while that for the humidity profile was 16%.(Che Yunfei,Ma Shuqing,Xing Fenghua,Li Siteng,Dai Yaru)

2.2 The extra-area effect in 71 cloud seeding operations during winters of 2008−2014 over Jiangxi Province,East China

Effects of weather modification operations on precipitation in target areas have been widely reported,but little is specifically known about the downwind (extra-area) effects in China.We estimated the extraarea effect of an operational winter (November–next February) aircraft cloud-seeding project in the northern Jiangxi Province in East China by using a revised historical target/control regression analysis method based on the precipitation data in winter.The results showed that the overall seasonal average rainfall at the downwind stations increased by 21.67% (p=0.0013).This enhancement effect was detected as far as 120 km away from the target area.Physical testing was used to compare the cloud characteristics before and after seeding on 29 November 2014.A posteriori analysis with respect to the characteristics of cloud units derived from operational weather radar data in Jiangxi was performed by tracking cloud units.Radar features in the target unit were enhanced relative to the control unit for more than two hours after the operational cloud seeding,which is indicative of the extra-area seeding effect.The findings could be used to help relieve water shortages in China.(Wang Weijian,Yao Zhanyu,Guo Jianping,Tan Chao,Jia Shuo,Zhao Wenhui,Zhang Pei,Gao Liangshu)

2.3 卫星云参数与飞机云物理探测对比研究和飞行方案设计

开展卫星反演云特性参数与飞机观测的对比研究，对于更好地发挥卫星遥感观测在天气、云物理和人工影响天气方面的探测优势具有重要意义。选取 2012年9月 21日一次层状云降水过程，对比分析 FY-2 与 MODIS反演云参数及飞机观测结果，探索了飞机检验卫星云参数的飞行方案。结果表明： FY-2 反演云参数演变趋势与飞机观测结果有较好的一致性; FY-2 反演有效粒子半径（Re）和光学厚度（τ）与MODIS反演的Re和τ间相关性较好，但此个例 FY-2 反演值普遍小于 MODIS 反演值; 探测区域 FY-2 反演Re频率分布与飞机观测Re分布有一定差异，FY-2 反演Re偏小，MODIS反演Re频率分布与飞机观测结果更为接近; 飞机观测计算得到的τ和液水路径值（LWP）与卫星反演τ和 LWP 差异较大，FY-2 反演值明显偏小。对于Re的检验，飞机最好在Re分布不大均匀的云顶作较长距离平飞观测; 对于 LWP 和τ等垂直积分参量的检验，飞机最好选择在光学厚度较均匀的小区域内螺旋爬升至云顶之上，再自云顶向下至最低高度进行垂直观测。(宋灿，周毓荃，赵洪升)

2.4 华北云特征参数与降水相关性的研究

利用河北省、河南省和山西省2013—2014年的每日10：00—15：00逐时 FY-2E 卫星反演得到的云结构特征参数和地面小时降水，统计分析了云顶高度、云顶温度、云光学厚度和云粒子有效半径等 4 类云结构特征参数与地面降水的关系。主要结论：随着云光学厚度的增加，降水概率呈增加趋势。云光学厚度比其他云参数对降水更具有指示意义，当云光学厚度大于 20 时，降水概率显著增大。双参数、多参数组合下，对地面是否出现降水的判断和识别要优于单个云参数的判别结果。4 类云参数中，云光学厚度与降水强度呈正相关关系，对降水强度的影响最为显著; 云顶温度和云顶高度对降水强度的影响次之; 云粒子有效半径与降水强度的关系不明显。地面降水时，当云光学厚度小于 20 或云光学厚度介于21～30、云顶温度大于 −15 ℃ 时，出现小雨的概率最大; 当云光学厚度介于21～30、云顶温度小于−15 ℃ 或云光学厚度大于 30、云顶温度大于−30 ℃ 时，出现中雨的概率最大; 当云光学厚度大于30、云顶温度小于−30 ℃ 时，出现大雨或暴雨的可能性最大。云光学厚度、云顶温度、云顶高度和云粒子有效半径等云结构特征参数组合使用，对判断降水概率和降水强度具有较好的指示作用。(王磊，周毓荃，蔡淼，申双和)

2.5 一次冷锋降水云系结构和人工增雨条件模拟分析

利用中尺度模式 ARPS 对 2013年10月13—14日华北南部到河南一次冷锋降水过程的数值模拟结果和卫星、雷达、飞机等观测资料，分析了冷锋云系不同部位宏微观结构和多种增雨潜力要素分布特征，初步探讨了冷锋云系增雨潜力区判别方法及分布特征。结果表明：此次降水过程冷锋云系结构具有不均匀性，云中含水量及其变化梯度自云系前部到后部逐步减小。冷锋云系不同位置垂直结构特征不同，云系前部自云底到云顶为整层上升气流区，云中存在典型的“催化—供给”结构，动力辐合和水汽条件较好，对应区域地面出现较大降水。云系后部上升气流区集中在中高层，4.0 km 以下为下沉气流，云中冰相粒子丰富，但中低层液态水含量少，“催化—供给”结构不明显，动力辐合和低空水汽条件差，对应区域地面降水微弱或不产生降水。利用模式模拟结果逐步判别云系增雨潜力条件，结果显示：增雨潜力区主要位于冷锋云系前部、地面冷锋与 700 hPa 切变线之间约 150 km 宽的狭长带状区域，云体是具有“催化—供给”结构的冷暖混合云，可催化层高度为 3.5～7.0 km。(刘艳华，周毓荃，黄毅梅，吴志会，秦彦硕)

2.6 飞机作业监测移动应用的设计与实现

人工影响天气飞机作业需要实时跟踪与展示飞行过程动态，并实现空中、地面指挥中心、地面不同机场三者之间信息交互与共享。通过设计并实现人工影响天气飞机作业实时监测移动应用系统（TEAM），可实时监测飞机作业并同步可视化共享于不同业务用户，解决飞机作业监测中作业信息采集渠道多样、标准不统一、共享范围小、飞机内外场交流渠道不畅等业务问题。TEAM针对指挥业务和信息集约化需求，提出具有普适性的国家级人工影响天气飞机作业实时监测的移动应用平台框架，包括海事、北斗双链路保障传输、安全加固体系和分层策略，用于解决数据和移动终端两方面面临的技术问题，可以作为人工影响天气飞机作业实时监测移动应用的标准化解决方案。TEAM开发使用HTML5 混合开发模式与Ionic / Angular JS技术，提高开发效率和终端运行性能。TEAM实时可视化显示人工影响天气飞机准备情况、飞行轨迹、播撒动态以及落地后总结简报、通知，从而解决了飞机整个作业过程中的各相关部门沟通效率和信息共享问题。目前TEAM覆盖全国80%以上的人工影响天气飞机的实时监测和作业信息共享，并应用于东北、华北、西北、西南、中部等多个区域人工影响天气飞机日常作业监测和重大应急服务一线指挥。移动应用程序响应迅速，运行稳定，作业监测和可视化效果良好，为人工影响天气飞机的实时监测提供了新的解决方案。(李德泉,李抗抗,李宏宇,戴艳萍,李集明)

3 科学观测试验

3 Scientific observation experiment

3.1 飞机外场观测

青藏高原探测试验。根据青藏高原云—降水飞机观测和微物理特征分析项目要求，在青海省果洛藏族自治区达日县开展针对云系垂直分布特征的空地一体联合探测。以达日试验点（99°39′N，33°45′E）为中心，半径35 km范围内，在4500～9000 m的垂直范围内，针对气溶胶、云、降水研究的飞行探测方案，并在2019年8月21日和22日，共开展了2个架次的探测飞行，共计6 h 42 min，得到了一次在达日地区对流云过程中的云降水的微物理特征。

西北区域人工影响天气科学试验项目。开展了针对祁连山试验区和六盘山试验区的空地联合观测试验。在祁连山试验区，以永昌和张掖为中心开展垂直探测，在六盘山试验区，以六盘山气象站、隆德气象站和泾源气象站为中心开展垂直探测。共计飞行8 h 6 min，在祁连山地区得到一次对流云降水消散期的云降水微物理垂直分布特征，在六盘山地区得到一次地形云降水过程的上层云和降水微物理特征的垂直分布。

华南地区飞机云物理探测试验。广东省珠海市以西沿海地区，针对华南强降水典型云系（特别是华南强降水台风外围云系）的宏微观特征开展协同观测。探测以阳江或汕尾为中心，半径30 km范围内，针对“气溶胶—云—降水研究”的方案。7月16日至19日，共开展了2个架次的探测飞行，共计飞行5 h 45 min，这两次飞行主要针对阳江和汕尾的气溶胶与云凝结核的垂直分布特征开展了探测。

南方大范围云系中的云微物理特征探测飞行。结合南方增雨雪抗旱服务、行业专项研究项目(南方大范围云系人工增雨作业潜力与作业技术研究)需求 ，开展针对江西赣州当地云降水过程的空地一体的观测研究，从而指导当地科学有效地开展人工影响天气业务工作。2019年底开展了7个架次的飞行探测/增雨工作，初步认识了当地冬季系降水系统云中微物理特征。

3.2 庐山等地局地云雾降水观测

高山云雾和降水观测（庐山）。以庐山云雾试验站为观测基地平台，2019年开展了全年的云雾降水的微物理观测试验、雾滴谱仪对比观测试验和庐山气溶胶—云雾—降水综合观测试验。在全年的常规云雾和降水观测中，共收集云雾个例28次，降水个例86次，其中冰雹6次，降雪1次，获取了山底至山顶的气溶胶缆车观测数据、云雾和降水期间的不同粒径段和种类气溶胶观测数据、云凝结核数据、雾水和雨水样本等。

3.3 北京雾和降水观测

作为城市气溶胶、雾霾和降水微物理特征的重要观测平台，长期开展观测试验以及平台的运维工作，试验人员每天进行日志记录。自2009年以来该平台积累了大量雾霾、降水和气溶胶观测数据，通过数据分析和研究，揭示了城市雾霾天气的物理机制，为人工影响雾霾天气提供了新的发展方向。

4 人工影响天气重大工程

4 Major weather modification projects

4.1 国家人工影响天气能力建设工程

积极推进国家人工影响天气项目初步设计编制和项目执行工作。完成国家人工影响天气项目初步设计编写，并上报中国气象局；完成冰雹防控基地、庐山云雾基地和重大活动保障基地3个外场试验基地设备的采购及合同签署工作。目前，正积极配合国家发展改革委评审中心核概。

4.2 东北区域人工影响天气工程

2019年4—8月，完成对省级东北人工影响天气项目子项目验收及集合验收。完成国王350增雨飞机系统验收及新舟60增雨飞机机载探测数据处理系统和机载液氮致冷剂催化播撒装置及改装工作。完成人工影响天气效果检验软件系统验收工作。5月完成人工影响天气效果检验软件系统测试。7月完成人工影响天气效果检验软件系统验收工作。编制高性能增雨飞机业务验收材料。完成了国家高性能增雨飞机建设情况、业务试运行情况、建设技术总结、系统测试、建设用户情况5个报告的编制工作，8月向中国气象局相关职能司上报了高性能飞机业务验收材料。

完成东北项目业务验收。2019年12月25日，由中国气象局应急减灾与公共服务司在北京组织召开了“新增千亿斤粮食工程东北区域人工影响天气能力建设项目”业务验收会，邀请了中国气象局、北京大学、中国科学院大气物理研究所、北京市人工影响天气办公室等单位9名专家组成专家组，余勇副局长出席业务验收会。东北人工影响天气项目办公室汇报了项目建设、业务试运行、作业服务和效益等情况，专家组认真审查了项目业务验收报告材料。经过质询讨论，专家组一致同意项目通过业务验收。

4.3 西北区域人工影响天气能力建设工程进展

完成4架国家飞机的采购，均进入飞机加改装阶段；完成全部人工影响天气探测装备的采购，大部分装备已投入使用；完成研究试验项目的招标和项目下达，7月份在已完成的6个外场试验示范基地（或试验点）全面开展试验研究；协同中国气象局气象干部培训学院完成了西北区域人工影响天气作业指挥人员培训班、西北区域双偏振多普勒天气雷达、云雷达及其资料应用培训班等。组织国内外科学家与西北各省人工影响天气科研人员共同探讨和开展了人工影响天气研究试验，激发了人工影响天气科技工作者的科研热情，推进了气象部门人工影响天气人才队伍的成长。

4.4 其他区域人工影响天气能力建设工程进展

组织咨询专家组和初设编制组赴中部区域相关省进行实地勘察，对项目初设的可行性、科学性和合理性进行了全面论证，完成初设技术审查。

5 人工影响天气业务与服务

5 Weather modification operations and services

5.1 国庆70周年、军运会、世博会、世园会服务保障

主动对接需求，精心做好国庆70周年保障各项技术准备工作，参与重大服务保障技术方案编制，完成北京人工影响天气办公室分两批6名技术骨干的技术培训；完成相关省局多个业务平台的升级和部署，实现数据采集与共享的通道畅通；精细化作业条件预报服务产品，加密人工影响天气作业条件监测服务；完成3架国家飞机设备巡检，确保适航状态。全力以赴，统筹调配人员、组建精干的保障团队；提前做好风险评估和应对预案；紧盯任务需求，圆满完成6次实战演练，共参加会商发言7次，制作发布各类服务专报18期，利用空地指挥系统对3架国家飞机进行全程跟踪监控，3架飞机累计飞行21架次，飞行时长61 h 36 min。

按照统一部署，选派专家和技术骨干赴武汉、上海，针对第七届世界军人运动会、世博会进行专项保障。就作业条件预报、作业方案设计及空域保障等提供现场技术指导，同时后方制作发布《人工影响天气作业条件预报和作业预案建议》专报，利用空地指挥系统对国家高性能增雨飞机进行全程跟踪监控。

5.2 重大抗旱减灾作业和应急服务保障

2019年春季四川省凉山州、山西、陕西发生森林火灾及北京、山西、河北、内蒙古、天津等北方地区持续干旱；秋冬季长江中下游和华南地区发生严重气象干旱，局地出现气象特旱，江西、安徽等省出现了几十年一遇的大旱。人工影响天气中心有针对性地对各地人工影响天气作业给出指导建议，有效地指导了各地人工增雨作业。增雨作业对森林灭火起到了重要作用、降低了华北等地的高森林草原火险等级、缓和了气象干旱、净化空气，并改善了土壤墒情，利于春播春耕工作的开展。在自然降水和人工增雨的共同作用下，各地旱情得到明显缓解。

5.3 实施人工增雨改善空气质量试验

按照生态环境部需求和中国气象局的部署，9月24日，中国气象局人工影响天气中心快速响应，编写《华北及周边地区人工增雨改善空气质量保障方案》。9月26日，刘雅鸣局长和余勇副局长亲临人工影响天气中心指挥改善空气质量增雨作业。截至29日，人工影响天气中心组织华北及周边9省（区、市）开展专题会商8次，制作发布各类服务专报55期。9省区开展了飞机增雨作业5架次，地面增雨作业94次。在实施科学作业中，中心在作业条件预判、作业方案制定、作业跟踪指挥、作业实施和效果分析等方面做了大量卓有成效的工作。通过试验，建立了国家级指挥、上下联动、多部门协同的工作流程，现代化装备和技术成果得到了充分检验，技术人才队伍得到了锤炼。

5.4 人工影响天气业务模式发展

完善CPEFS_V1.0、MM5-CAMS、GRAPES-CAMS3类云模式初设场，实现稳定支撑全国人工影响天气作业条件潜力预报业务。发展了CPEFS-SEED 催化模式，初步实现业务运行，进一步改进了 LAPSCPEFS 同化模式系统，2019年在多次重大业务服务中发挥重要作用。研发了积冰/过冷水潜势预报中期产品，并试应用。研发了预报云场检验方案，开展云预报产品批量检验。

5.5 作业条件监测指挥及云水资源评估利用

研发FY3/FY4卫星人工影响天气云特性参量，升级作业条件监测产品，在地基气象观测条件较差，森林草原火灾的易发区，风云卫星人工影响天气云产品极大地弥补了常规观测的空白和不足。优化发展了飞机和卫星、雷达遥感识别过冷水的方法，初步构建作业条件星-空-地综合监测识别技术体系。发展了目标区飞机以及火箭高炮充分连片催化的作业设计方案，推广应用各地，有效提升全国作业设计水平。完善云水资源概念和评估方法，优化建立固定目标区云水资源耦合开发利用技术，并开展示范应用。

5.6 效果检验和评估

完善针对不同作业方式催化剂扩散传输计算方案，开发作业影响区自动计算系统，在国家CPAS平台上优化系统功能。发展了基于扩散传输计算的区域多参量动态对比效果检验方法，多次在跨区域联合作业和重大过程人工影响天气服务保障中发挥作用。发展了基于“TITAN”雷达回波追踪算法的人工影响天气二次开发，实现对流云的作业效果评估，并在CPAS业务平台实现自动计算。完善人工影响天气作业信息全要素采集，提出作业合理性评估方案，开展人工影响天气服务决策材料效果估算研究和应用，初步构建国家级效果检验业务。

5.7 国家人工影响天气飞机运行业务

全力做好3架国家增雨飞机的运行及安全管理，国家作业飞机停靠地咸阳、格尔木、和田、巴彦淖尔为国家及地方作业飞机停场、维护、通信、增雨作业提供保障服务。组织飞机托管公司（三星通航和北大荒通航）按时保质地完成新舟60（30M，36M）和空中国王350ER增雨飞机（200H）的定检维修维护工作。

在库尔勒机场、克拉玛依机场和吐鲁番机场开展2019年冬季飞机人工增水探测和播撒作业。在六盘山区开展了一次云微物理飞行探测。2020年将在试验区内正式开展带电离子外场催化试验工作。

5.8 人工影响天气装备及安全业务

在省级前期试点基础上，利用条码和射频识别技术、声电光自动感应技术和移动互联技术等，建设人工影响天气装备和弹药从生产、验收、转运、仓储到发射的全程监控系统，建设飞机与地面作业信息的自动采集系统，选择4个省(市)分别建立不同技术模式的省级应用示范，实现人工影响天气作业装备与弹药的全程、规范、自动化的实时监控与管理，提出可用于全国各省市推广的技术模式与系统，提高人工影响天气作业安全管理的科技水平和业务现代化程度。

建设完成两套系统：作业装备弹药全程监控系统和作业信息实时采集监控系统；制定了3套技术标准与规范：人工影响天气作业装备和弹药产品统一标识规范，飞机作业信息采集传输规范，地面作业信息采集传输规范；研发一套国家级人工影响天气作业装备弹药信息管理与作业信息实时采集监控系统软件。机载端作业监视管理系统已经在全国推广建设，至2019年底，与全国30个省级人工影响天气装备物联网管理系统实现联网和数据上传。

完成2019年全国业务用催化剂成核率检测任务，为各厂商催化剂催化效率提供了客观依据，有利于全国云雾催化工作的开展。

5.9 生态修复型人工影响天气作业技术指南

编制了生态修复型人工影响天气作业技术指南，从生态修复型人工影响天气业务特点、总体技术思路及关键技术、业务流程、试点示范区的应用等方面全面指导生态修复型人工增雨雪作业。结合国家重点研发项目“云水资源评估研究和利用示范”，针对南水北调中线丹江口水源地蓄水、生态环境改善及南方抗旱，在湖北示范区开展了固定目标区的人工增雨试验。

5.10 改善空气质量科学试验技术指南

牵头编制改善空气质量人工影响天气科学试验指南，从人工增雨改善空气质量的理论基础、试验目标和主要内容、增雨减污试验方案设计及关键技术、试验流程、人工增雨减污试验典型个例、试验总结等方面全面指导改善空气质量人工影响天气科学试验的开展。完成2018年上海中国国际进口博览会人工增雨改善空气质量保障试验技术总结报告，并提交减灾司。联合北京市气象局、国家气象中心、生态环境部环境监测总站，牵头编制“2019年近期华北人工增雨改善空气质量试验方案”，并由减灾司发文下发相关省份。4月指导河南等省开展人工增雨改善空气质量试验。9月中下旬，开展了华北人工增雨改善空气质量试验。