大氣物理與人工影響天氣

云物理與人工影響天氣研究進展

Advances in Research on Cloud Physics and Weather Modification

1 人工影響天氣機理與方法

1 Mechanism and method of weather modification

1.1 Cable-car measurements of vertical aerosol profiles impacted by mountain-valley breezes in Lushan Mountain, East China

In-situ field observations of vertical aerosol profiles for one month in complex terrain (Lushan Mountain,China) were carried out using a cable car, which resolved detailed vertical distributions of mountain aerosols with lowcost operation. Cable-car observations were conducted during the early morning and late afternoon,when mountain and valley winds dominated, respectively. The diurnal aerosol variations at the top and foot of Lushan Mountain were analyzed based on environmental and meteorological stations. The observations indicated that the mountain-valley breezes notably impacted the mountain-area aerosol distribution under weak weather conditions. More uniform aerosol profiles for the afternoon than the morning, with their decreasing rates of PM2.5(particles with diameters less than 2.5 μm) were 1.64 and 2.28 μg m?3hm?1, respectively. The PM2.5/PM10ratio at the mountain top increased from 0.69 to 0.81, and that at the mountain base decreased from 0.75 to 0.70 from morning to afternoon. The PM2.5concentration decreased in and around Lushan Mountain from daytime to nighttime, with the impacted diameter of the 300-m topography line being smaller than about 5 km, while the concentration increased in Jiujiang City. The relative decreasing rate of PM2.5was higher at the mountain top site (about 20%) than at the base site (about 2%) from daytime to nighttime. Moreover, uniform aerosol profiles could have been caused by regional transport through a relatively strong low-level synoptic flow (about 5 m s?1) and the mountain’s dynamic lifting effect. （Duan Jing, Chen Yong, Wang Wenling, Li Jun,Zhang Xiaopeng, Lu Guangxian, Che Yunfei, Zhong Shujun, Ma Shupo, Li Peng, An Junling, Fu Pingqing）

1.2 Radiative effects of clouds and fog on long-lasting heavy fog events in northern China

In the last decade, heavy fog events have been found to last from several days to more than a week and frequently occur in the northern China. The mechanism responsible for the long-lasting heavy fog events has not been fully understood. In this study, the radiative effects of the clouds and fog on two persistent heavy fog events on December 3–6, 2011 (Case-2011) and January 28–31, 2013 (Case-2013) are investigated based on both observations and weather research and forecasting (WRF) model. The results indicate that the radiative effects of clouds formed at middle and high levels and fog may play an important role in sustaining longlasting fog events in the northern China. The clouds formed above the fog primarily consist of ice and snow particles with a thickness of more than 3–4 km and cloud base of 3–6 km. During the daytime, the increase in solar radiation reflection caused by both clouds and fog can reduce the mean surface solar radiation by 71% in Case-2011 and 84% in Case-2013, and the contribution from clouds accounts for 18%, which may significantly weaken the surface heating from solar radiation and prevent the dissipation of fog events. While during the nighttime, the greenhouse effect of clouds and fog can increase the mean surface net radiation by 77 W m?2in Case-2011 and 68 W m?2in Case-2013, which may reduce the surface long-wave radiative cooling and prevent the further development of fog events. However, the greenhouse effect of clouds and fog during both daytime and nighttime may enhance turbulent processes and cause the fog to rise, and remain in the stable inversion layer.（Guo Lijun, Guo Xueliang, Luan Tian, Zhu Shichao, Lyu Kai）

1.3 Characteristics of raindrop size distributions during Meiyu season in Mount Lushan, East China

Meiyu front precipitation makes the region prone to frequent floods, mudslides, landslides, and other disasters, and has been the focus of ongoing and challenging meteorological research. Investigation of the raindrop size distribution (RSD) is essential for exploring the characteristics and underlying physical precipitation processes. This study investigated the precipitation characteristics in Lushan mountainous areas during the Meiyu season using laser disdrometer observed RSD data from 2016 to 2019. For the average spectra of five rain rate classes, the concentrations of large raindrops (> 0.5 mm) increased with rain rate(R), while the concentrations of small raindrops (< 0.5 mm) increased only under rain rates higher than 10 mm h?1. The gamma distribution parameters of N0(intercept parameter) and λ (slope parameter) increased/decreased with rain rate, and the shape parameter μ exhibited negative values in different rain rate classes.The distribution pattern features were N(D) = 721D?1.79e?1.20D. Distributions of the frequency for massweighted mean diameter (DM) and the logarithm of the generalized intercept parameter (lgNw) both showed a unique bimodal type, and an exceptionally high NW(lgNw> 4.5) subset with small DMwas determined.The stratiform and convective rain of RSD were also investigated. DM-R and NW-R showed similar variations in two types of precipitation. The lower μ values resulted in higher primary and constant coefficients in the quadratic polynomial fitting for the μ-λ relationship (λ = 0.0347μ2+ 1.180μ + 2.495 ). The Z-R relationship (Z for radar reflectivity factor) in stratiform precipitation characteristics was Z = 203R1.59. Further investigations showed that high NWvalues usually occurred in persistent precipitation. The RSD can be characterized as high concentrations of the first two diameter classes with narrow spectrum width (< 1 mm), which were captured during in-cloud rain with a low but continuous rain rate (< 5 mm h?1). The mountainous topography plays an important role in reshaping the characteristics of RSD and the physical processes of precipitation. （Chang Yi,Ma Qianrong, Guo Lijun, Duan Jing, Li Jun, Zhang Xiaopeng, Guo Xueliang, Lou Xiaofeng, Chen Baojun)

1.4 Aerosol and cloud properties over a coastal area from aircraft observations in Zhejiang, China

Using in-situ aircraft observations from six flights over Zhejiang on September 1 and September 4, 2016,this study investigates differences in aerosol and cloud properties between daytime and nighttime. The samples were divided into marine type and continental type based on the backward air mass trajectories and aerosol characteristics. The results show that the aerosol number concentration (Na) near the ground during daytime is higher than that at nighttime. During daytime, Nahas a significant decreasing trend near the top of the planetary boundary layer (PBL), which is not obvious during nighttime. There may be still a relative high concentration of aerosols remaining in the transition zone between the PBL and the free troposphere. Under similar liquid water content (LWC) conditions, the cloud droplet number concentration (Nc) at night is lower, and the cloud droplet effective diameter (cloud ED) is larger. The total Naof marine type aerosols is generally lower than that of continental type aerosols, but for aerosols with particle diameters greater than 1 μm, the marine type aerosols are higher. The study shows a strong negative Na-cloud ED relationship for marine type aerosols, but no obvious Na-cloud ED relationship for continental type aerosols. The number of cloud condensation nuclei (CCN)is higher under high-Naconditions; the ratio of CCN to Nareveals that the activation efficiency of marine type aerosols is higher than that of continental type aerosols. There is no obvious difference in activation efficiency between day and night. (Che Yunfei, Zhang Jing, Fang Chungang, Zhou Xu, Xue Wenhao, Hu Xiaomin, Duan Jing, Li Wei, Gao Yang, Lu Guangxian, Zhao Delong, Zhao Chuanfeng)

1.5 An airborne study of the aerosol effect on the dispersion of cloud droplets in a drizzling marine stratocumulus cloud over eastern China

Detailed airborne measurements were carried out to explore aerosol-cloud interactions and cloud microphysical properties in a drizzling marine stratocumulus cloud deck over the eastern China. Results show that the collisioncoalescence of cloud droplets, the condensation of small droplets, and the collision-induced break-up of drizzle were the dominant microphysical processes in the sampled water cloud parcel. The region in the vicinity of the cloud’s lateral boundary was spatially divided into sub-regions to better understand aerosol and droplet interactions. Relationships between the relative dispersion (ε) and the cloud’s microphysical and dynamical characteristics were also examined. A negative relation was found between ε and the cloud droplet number concentration, with ε showing a close relationship with the liquid water content (LWC) and updraft velocity. When LWC was greater than about 0.75 g kg?1, the range of ε values narrowed, and updrafts dominated. By introducing ε in the cloud droplet effect radius (Re) parameterization, we find that ε can further affect indirect forcing by changing the Redistribution for the cloud examined in this study. The dispersion effect (DE) was estimated using the effective radius ratio and the specific cloud water content. An in-depth analysis indicates that DE may offset the Twomey effect by about 12%. Two different methods of estimating the indirect effect (IE) yielded close values (0.084 and 0.077), suggesting that introducing DE into the estimation had a small influence on the IE calculation in the drizzling marine stratocumulus cloud of this study.Note that the estimated IE has a large uncertainty, given the large biases in the cloud properties measured. (Wang Fei, Li Zhanqing, Zhao Delong, Ma Xincheng, Gao Yang, Sheng Jiujiang, Tian Ping, Maureen Cribb)

1.6 Revisiting the size of nonspherical particles recorded by optical array probes with a new method based on the convex hull

In recent years, the cloud imaging probe (CIP) and precipitation imaging probe (PIP) produced by droplet measurement technologies (DMT) have been introduced by a number of meteorological research and operation centers in China. The supporting software provided by DMT, i.e., PADS (particle analysis and display system),cannot output detailed information on each individual particle, which definitely limits the in-depth utilization of cloud and precipitation particle image data in China. In this paper, particle-by-particle information was extracted by decompressing the CIP and PIP original particle image data, based on which a new definition of the dimension for nonspherical particles is proposed by using the area of the convex hull enclosing a particle to obtain the equivalent diameter of a circle with equal area. Based on the data detected during one flight in Inner Mongolia, the particle size distribution obtained using the new particle size definition and that used by the other four existing definitions are compared. The results show that the particle number concentration calculated using different particle size definitions can vary by up to an order of magnitude. The result obtained based on the new particle size definition is closest to that calculated with the area-equivalent diameter definition.（Zhang Rong, Zhou Xu, Li Hongyu, Li Hanchao, Wei Lei, Gao Yang, Xia Qiang, Wang Xiangyu）

1.7 Satellite estimates and subpixel variability of rainfall in a semi-arid grassland

Uncertainties in satellite rainfall estimation may derive from both the local rainfall characteristics and its subpixel variability. To study this issue, micro rain radars and a rain gauge network were deployed within a 9-km satellite pixel in the semi-arid Xilingol grassland of China in summer 2009. The authors characterized the subpixel variability with the coefficient of variation (CV) and evaluated the satellite rainfall estimation for this semi-arid area. The results showed that rainfall events with a high CV were mostly convective with a small amount of rainfall. Spatially inhomogeneous rainfall was most likely to occur at the edges of small clouds producing rain. The performance of the TRMM (tropical rainfall measuring mission) 3B42V7 product for daily rainfall was better than that of the CMORPH (Climate Prediction Center morphing technique) and PERSIANN(precipitation estimation from remotely sensed information using artificial neural networks) products, although the TRMM product tended to overestimate rainfall in a lake area of the semi-arid grassland. (Chen Yong, Duan Jing, An Junling, Liu Huizhi, Ulrich G?rsdorf, Franz H. Berger)

1.8 A hypergraph-embedded convolutional neural network for ice crystal particle habit classification

In the field of weather modification, it is important to accurately identify the ice crystal particles in ice clouds. When ice crystal habits are correctly identified, cloud structure can be further understood and cloud seeding and other methods of weather modification can be used to change the microstructure of the cloud.Consequently, weather phenomena can be changed at an appropriate time to support human production and quality of life. However, ice crystal morphology is varied. Traditional ice crystal particle classification methods are based on expert experience, which is subjective and unreliable for the identification of the categories by threshold setting. In addition, existing deep learning methods are faced with the problem of improving classification performance on datasets with unbalanced sample distributions. Therefore, we designed a convolutional neural network (CNN) embedded with a hypergraph convolution module, named Hy-INet. The hypergraph convolution module can effectively capture information from hypergraphs constructed from local and global feature spaces and learn the features of small samples in ice crystal datasets that have unbalanced sample numbers. Experimental results demonstrate that the proposed method can achieve superior performance in the classification task of ice crystal particle habits.（Liao Mengyuan, Duan Jing, Zhang Rong, Zhou Xu, Wu Xi, Wang Xin, Hu Jinrong）

1.9 Temporospatial distribution and trends of thunderstorm, hail, gale, and heavy precipitation events over the Tibetan Plateau and associated mechanisms

Temporospatial distribution and trends of thunderstorm, hail, gale, and heavy precipitation events over the Tibetan Plateau (TP) as well as the associated mechanisms with observational data from 1979 to 2016 are investigated, which have not been fully studied under a changing climate. The results indicate that thunderstorm, hail, and gale events over the whole TP show significant decreasing trends, while heavy precipitation events have an insignificant increasing trend. The southeast and central south subregions have obvious significant decreasing trends in thunderstorm, hail, and gale events, while the northeast subregion has a significant increasing trend in heavy precipitation events. It is found that the atmospheric circulation anomaly caused by the northwestern Atlantic sea surface temperature (SST) anomaly associated with the North Atlantic oscillation (NAO) should be responsible for these changes. A strong wave train triggered by the northwestern Atlantic SST anomaly propagates from the northern Atlantic to East Asia through Europe, and induces a more upper-level warming over the TP and an anomalous anticyclonic circulation near the Lake Baikal, resulting in a more stable atmosphere and blocking effect, which forces the midlatitude westerlies and associated cold air to shift poleward. The weakened cold-air advection over the TP decreases the baroclinic instability and convection initiation, and finally causes the significant decreasing trends in severe weather events. On the other hand, the enhanced easterly winds in the southern flank of the anticyclonic circulation can significantly increase the water vapor flux from the eastern boundary of the TP and heavy precipitation events in the northeast subregion. (Tang Jie, Guo Xueliang, Chang Yi, Lu Guangxian, Qi Peng)

1.10 Microphysical characteristics of precipitating cumulus cloud based on airborne Ka-band cloud radar and droplet measurements

Based on cloud-probe data and airborne Ka-band cloud radar data collected in Baoding on 5 August 2018, the microphysical structural characteristics of cumulus (Cu) cloud at the precipitation stage were investigated. The cloud droplets in the Cu cloud were found to be significantly larger than those in stratiform(STF) cloud. In the Cu cloud, most cloud particles were between 7 and 10 μm in diameter, while in the STF cloud the majority of cloud particles grew no larger than 2 μm. The sensitivity of cloud properties to aerosols varied with height. The cloud droplet effective radius showed a negative relationship with the aerosol number concentration (Na) in the cloud planetary boundary layer (PBL) and upper layer above the PBL. However, the cloud droplet concentration (Nc) varied little with decreased Nain the high liquid water content region above 1500 m. High Navalues between 300 and 1853 cm?3were found in the PBL, and the maximum Nawas sampled near the surface in August in the Hebei region, which was lower than that in autumn and winter. High radar reflectivity corresponded to large FCDP (fast cloud droplet probe) particle concentrations and small aerosol particle concentrations, and vice versa for low radar reflectivity. Strong updrafts in the Cu cloud increased the peak radius and Nc, and broadened the cloud droplet spectrum; lower air temperature was favorable for particle condensational growth and produced larger droplets.（Wei Lei, Huang Mengyu, Zhang Rong, Lyu Yuhuan,Hou Tuanjie, Lei Hengchi, Zhao Delong, Zhou Wei, Fu Yuan）

1.11 Characteristics of raindrop size distributions in Chongqing observed by a dense network of disdrometers

This study investigates the characteristics of raindrop size distribution (RSD) including the temporal and spatial variabilities and the summer rain RSD features using 34 Parsivel disdrometers data from January 2015 to January 2016 in Chongqing, an inland municipality in Southwest China. The observed RSDs are fitted with the gamma distribution (N(D) = N0Dμe?λD) in this study. Rainfall in summer differs greatly from winter with larger rain rate, rain water content and variabilities. From winter to summer, raindrop sizes increase as the frequency of convective rain increases, and the diurnal variabilities of raindrop sizes are greatly enlarged. The spatial variabilities of N0, λ and μ are relatively weak and change little in summer. The summer rainfall RSD characteristics and parameter relationships in Chongqing are different from other regions (Nanjing, Beijing,Zhuhai and Daocheng) in China. A novel diagnosed relation between the shape parameter of the gamma distribution (μ) and the mean volume diameter (Dv) is proposed based on the large amount of observations,which allows for a wider range of the mean volume diameter of raindrops compared to traditional μ-λ relations in microphysics parameterizations. (Liu Xuancheng, Xue Lulin, Chen Baojun, Zhang Yixuan)

1.12 Numerical simulation and the underlying mechanism of a severe hail-producing convective system in East China

A severe convective system that produced egg-sized hail in Jiangsu Province in East China on April 28,2015 was simulated using a cloud-resolving weather research and forecasting model with the spectral bin microphysics scheme. The simulation reproduced the two stages of the convective system: the linear convective system (LCS) and the bow echo system (BES) stages. During the LCS stage, the intensity of updrafts was slightly stronger than that in the BES stage, with abundant supercooled water above the ?20 layer, and graupel and hail mainly generated in this period. The microphysical budget analyses and size distribution characteristics of hail were studied within one cell that produced hail during the LCS. It was suggested that hail mainly formed through water-graupel collision and increased in size by collecting liquid water. Hail particles with smaller diameter were located around the perimeter of the main updrafts, while larger ones were distributed at the left edge of the updrafts. Trajectories and size growth processes of hailstones within the chosen cell were calculated by a three-dimensional hail growth model, and it was found that hails originated from the middle levels on the east side of the updrafts, and were transformed westward and downward to the lower levels. They continued to ascend along the left edge of the updrafts and experienced one or more updown recycles and fell down to the ground on the west side of the updrafts. (Lei Yin, Fan Ping, Xu Huanbin,Chen Baojun)

1.13 Characteristics of deep convective systems and initiation during warm seasons over China and its vicinity

The spatiotemporal statistical characteristics of warm-season deep convective systems, particularly deep convective systems initiation (DCSI), over China and its vicinity are investigated using Himawari-8 geostationary satellite measurements collected during April-September from 2016 to 2020. Based on a satellite brightness temperature multiple-threshold convection identification and tracking method, a total of 47593 deep convective systems with lifetimes of at least 3 h were identified in the region. There are three outstanding local maxima in the region, located in the southwestern, central and eastern Tibetan Plateau and Yunnan-Guizhou Plateau, followed by a region of high convective activities in South China. Most convective systems are developed over the Tibetan Plateau, predominantly eastward-moving, while those developed in Yunnan-Guizhou Plateau and South China mostly move westward and southwestward. The DSCI occurrences become extremely active after the onset of the summer monsoon and tend to reach a maximum in July and August, with a diurnal peak at 11:00?13:00 LST in response to the enhanced solar heating and monsoon flows.Several DCSI hotspots are identified in the regions of inland mountains, tropical islands and coastal mountains during daytime, but in basins, plains and coastal areas during nighttime. DCSI over land and oceans exhibits significantly different sub-seasonal and diurnal variations. Oceanic DCSI has an ambiguous diurnal variation,although its sub-seasonal variation is similar to that over land. It is demonstrated that the high spatiotemporal resolution satellite dataset provides rich information for understanding the convective systems over China and vicinity, particularly the complex terrain and oceans where radar observations are sparse or none, which will help to improve the convective systems and initiation nowcasting. (Li Yang, Liu Yubao, Chen Yun, Chen Baojun, Zhang Xin, Wang Weisheng, Shu Zhuozhi, Huo Zhaoyang)

1.14 Hydrometeor and latent heat nudging for radar reflectivity assimilation: Response to the model states and uncertainties

Radar data are essential to convection nowcasting and nudging-based radar data assimilation through diabatic initialization is one of the most effective approaches for forecasting convective systems with numerical weather prediction (NWP) models, used at several advanced global weather centers. It is desired to assess the uncertainty and physical consistency of this assimilation process. This paper investigated impacts of relaxation coefficient, radar data update intervals and continuous assimilation time duration and addressed the key issues and possible solutions of the radar data assimilation based on the WRF hydrometeor and latent heat nudging (HLHN) developed at the National Center for Atmospheric Research (NCAR). It is revealed that excessively large re-laxation coefficient forced the model to observations with a tendency greater than the physical terms of the convection, causing the dynamic imbalances and serious convection “ramp-down”right after the free forecast starts. Assimilating high update frequency radar data can make the tendency terms moderate and sustained thereby maintaining the assimilation effect and reducing fortuitous convection. HLHN requires a minimum continuous assimilation duration to contain the initial forced disturbance of the model. For a summer Meiyu precipitation case studied, the minimum duration is about 1 h. Appropriate selection of the HLHN parameters is able to effectively improve the temperature, humidity, and dynamic fields of the model. In addition, several issues still remain to be solved to further enhance HLHN.（Huo Zhaoyang, Liu Yubao, Wei Ming, Shi Yueqin, Fang Chungang, Shu Zhuozhi, Li Yang）

1.15 Vertical distributions of aerosol microphysical and optical properties based on aircraft measurements made over the Loess Plateau in China

Aerosol microphysical properties, scattering and absorption characteristics, and in particular, the vertical distributions of these parameters over the eastern Loess Plateau, were analyzed based on aircraft measurements made in 2020 during a summertime aircraft campaign in Shanxi, China. Data from six flights were analyzed.Statistical characteristics and vertical distributions of aerosol concentration, particle size, optical properties,including aerosol scattering coefficient (σsp), backscattering ratio (βsc), ?ngstr?m exponent (α), single-scattering albedo (SSA), partially-integrated aerosol optical depth (PAOD), and black carbon concentration (BCc),were obtained and discussed. Mean values of aerosol particle number concentration (Na), particle volume concentration (Va), mass concentration (Ma), surface concentration (Sa), and particle effective diameter (EDa)were 854.92 cm?3, 13.37 μm3cm?3, 20.06 μg m?3, 170.08 μm3cm?3, and 0.47 μm, respectively. Mean values of BCc, σsp(450, 525, 635 nm), βsp(525 nm), α (635/450), and SSA were 1791.66 ng m?3, 82.37 Mm?1at 450 nm,102.57 Mm?1at 525 nm, 126.60 Mm?1at 635 nm, 0.23, 1.47, and 0.92, respectively. Compared with values obtained in 2013, Nadecreased by 60% and Madecreased by 45%, but the scattering coefficients increased in different degrees. In the vertical direction, aerosol concentrations were higher at lower altitudes, decreasing with height. Vertical profiles of σsp, βsp, α (635/450), and BCc measured during the six flights were examined.Two peaks in Nawere identified near the top of the boundary layer and between 2000 and 2200 m. Fine particles with EDa smaller than 0.8 μm are dominant in the boundary layer and coarse aerosols existed aloft.Aerosol scattering properties and BCc in the lowest layer of the atmosphere contributed the most to the total aerosol radiative forcing. SSA values were greater than 0.9 below 2500 m, with lower values at higher levels of the atmosphere. On lightly foggy days, SSA values were greater than 0.9, and aerosols played a cooling role in the atmosphere. On hazy days, lower level SSA values were generally greater than 0.85, with aerosols likely having a warming effect on the atmosphere. The 48-hour backward trajectories of air masses during the observation days showed that the majority of aerosol particles in the lower atmosphere originated from local or regional pollution emissions, contributing the most to the total aerosol loading and leading to high values of aerosol concentration and radiative forcing. (Cai Zhaoxin, Li Zhanqing, Li Peiren, Li Junxia, Sun Hongping,Yang Yiman, Gao Xin, Ren Gang, Ren Rongmin, Wei Jing)

1.16 Assimilation of ground-based microwave radiometer on heavy rainfall forecast in Beijing

Ground-based microwave radiometers (MWRPS) can provide continuous atmospheric temperature and relative humidity profiles for a weather prediction model. We investigated the impact of assimilation of groundbased microwave radiometers based on the rapid-refresh multiscale analysis and prediction system-short term(RMAPS-ST). In this study, five MWRP-retrieved profiles were assimilated for the precipitation enhancement that occurred in Beijing on 21 May 2020. To evaluate the influence of their assimilation, two experiments with and without the MWRPS assimilation were set. Compared to the control experiment, which only assimilated conventional observations and radar data, the MWRPS experiment, which assimilated conventional observations, the ground-based microwave radiometer profiles and the radar data, had a positive impact on the forecasts of the RMAPS-ST. The results show that in comparison with the control test, the MWRPS experiment reproduced the heat island phenomenon in the observation better. The MWRPS assimilation reduced the bias and RMSE of 2-meter temperature and 2-meter specific humidity forecasting in the 0–12 h of the forecast range. Furthermore, assimilating the MWRPS improved both the distribution and the intensity of the hourly rainfall forecast, as compared with that of the control experiment, with observations that predicted the process of the precipitation enhancement in the urban area of Beijing.（Qi Yajie, Fan Shuiyong, Li Bai, Mao Jiajia,Lin Dawei）

1.17 How do multiscale interactions affect extreme precipitation in eastern central Asia?

The variability of extreme precipitation in the eastern central Asia (ECA) during summer (June–August) and its corresponding mechanisms were investigated from a multiscale synergy perspective. Extreme precipitation in ECA displayed a quasi-monopole increasing pattern with abrupt change since 2000/2001,which was likely dominated by increased high-latitude North Atlantic SST anomalies as shown by diagnosed and numerical experiment results. Increased SST via adjusting the quasi-stationary wave train that related to the negative North Atlantic oscillation (NAO) and the east Atlantic/western Russia (EA/WR) pattern guided the cyclonic anomaly in central Asia, deepened the Lake Balkhash trough, and enhanced the moisture convergence in ECA. These anomalies also exhibited interdecadal enhancement after 2000. On the synoptic scale, two synoptic transient wave trains correlated with extreme precipitation in ECA by amplifying the amplitude of the quasi-stationary waves and guiding transient eddies in ECA. The induced transient eddies and deepened Lake Balkhash trough strengthened positive meridional vorticity advection and local positive vorticity,which promoted ascending motions, and guided the southerly warm moisture in ECA especially after 2000.Meanwhile, additional mesoscale vortices were stimulated and strengthened near the Tianshan Mountain in front of the wave trough, which, together with the enhanced meridional circulation, further increased extreme precipitation in ECA.（Ma Qianrong, Zhang Jie, Ma Yujun, Asaminew Teshome Game, Chen Zhiheng, Chang Yi, Liu Meichen）

1.18 人工影響天氣碘化銀催化劑研究進展

碘化銀（AgI）類催化劑是人工影響天氣外場試驗和業務作業中使用最廣泛的催化劑，其核化效率和核化機制在很大程度上影響催化效果。在總結美國、中國和歐洲多個國家利用云室和風洞研究AgI類催化劑的核化機制、核化閾溫及成核率的室內試驗成果的基礎上，梳理利用室內試驗成果發展的AgI數值催化模式，旨在為下一步優選新型高效AgI類催化劑和改進數值催化模式提供借鑒。AgI類催化劑核化機制包括凝華核化、接觸凍結核化、凝結凍結核化和浸沒凍結核化，其核化過程受大氣溫濕條件、催化劑粒子大小、成分等多種因素影響，并與催化劑粒子的燃燒溶液法、燃燒焰劑法和爆炸法等發生方式有關。目前國內外使用的AgI類催化劑含有不同成分，有多種催化劑粒子產生方式，催化劑粒子的核化機制和成核率有很大差異。將來應重點基于高性能云室和風洞，分析不同催化劑配方的核化機制和成核率，優選新型高效催化劑，改進AgI數值催化模式。（樓小鳳，傅瑜，蘇正軍）

1.19 青藏高原夏季對流云微物理特征和降水形成機制

青藏高原對我國天氣、氣候和水循環過程有重要影響。利用第三次青藏高原大氣科學試驗（TIPEX-Ⅲ）2014年7月在那曲地區的飛機觀測數據，研究青藏高原夏季對流云和降水的微物理特征及降水形成機制。飛機探測的云系主要為初生或發展階段的冰水混合云，云滴數濃度低于平原、海洋地區1～2個量級，云內存在大量大云滴和雨滴，過冷水含量高。大粒子（D≥50 μm）數濃度量級為100～101/L，云內上升氣流速度集中在1～4 m/s。青藏高原云滴譜主要呈雙峰型，云內冰相粒子多為密實、不透明的霰粒子，云內凇附過程顯著。云內暖雨過程產生的大云滴和雨滴有利于冰相過程，尤其是凇附過程的產生，使得青藏高原云更易產生降水。此外，殘留云系與對流云有著較為類似的微物理特征。（常祎，郭學良，唐潔，盧廣獻，亓鵬）

1.20 基于探空云識別方法的云垂直結構分布特征

云的垂直結構特征作為云重要的宏觀特征之一，直接決定了云的類型，進而通過發射和吸收輻射的方式影響著地氣系統的能量收支平衡，因此對云垂直結構特征的研究一直都是云物理研究的一個重要方向。作為觀測云垂直結構特征的一種方式，探空氣球通過獲取沿路徑方向高分辨率的廓線信息，采用一定反演方法從而能夠較為準確地識別云的垂直結構。本文即利用我國業務布網探空站的觀測資料，采用相對濕度閾值法識別云垂直結構，并同激光云高儀、“風云四號”靜止衛星和毫米波云雷達對識別的云結構特征量進行了一致性檢驗。在此基礎上，統計分析了2015—2017年單層、兩層和三層云的垂直結構分布特征、日變化和季節變化特征以及全國區域分布特征。結果表明：（1）整體分布上，單層云在垂直方向上出現的高度范圍介于多層云的高度范圍內，并且隨著云層數的增加，云在垂直方向上更為伸展，即高層云越高，低層云越低。（2）在日變化中，中午單層和多層云中最低層云的云底高度均高于早晨，而夜間單層和多層云中最高層云的云頂高度則高于早晨和中午，同時中間層云厚的變化要小于最上層和最下層云厚的變化。（3）在季節變化中，夏季云量較其他季節更多，云體發展也更為深厚，表明溫暖的大氣條件更有利于云的形成和發展。（4）我國云垂直結構分布特征具有明顯的緯向變化趨勢，從以青藏高原為中心的西南地區的云底較高云體較薄的云，逐步過渡到以東南沿海地區為中心的云底較低云體較為深厚的云，表明不同地形和氣候帶的差異與不同云類型的分布直接相關。（李琦，蔡淼，周毓荃，唐雅慧，歐建軍）

1.21 六盤山地區一次低槽低渦云系結構及其降水機制的數值模擬研究

六盤山是西北重要的水源涵養林基地，干旱少雨制約了該地區農業和經濟發展。作為該地區人工增雨技術研究的基礎，本文利用WRF模式對2018年8月21日發生在寧夏南部六盤山區的一次降水天氣過程進行了數值模擬。根據模擬結果結合實測資料，分析了造成此次強降水過程的有利環流形勢場，重點討論了山區降水云系的微物理結構以及降水形成機制。結果表明：降水是在高空槽配合低渦的動力場作用下形成的，受六盤山地形的阻擋作用，低層低渦系統移速落后于高空槽；垂直方向上云系呈現“催化—供給”的分層結構，但在云系不同部位，各層水凝物配置不同，導致冷暖云過程對降水的貢獻差異；六盤山東部迎風坡降水強于西坡。霰粒子融化和云水碰并是地面降水的主要來源；碰凍過冷雨水是霰增長的主要過程。迎風坡云水層深厚，含水量高，一方面促進過冷層中霰粒子的碰凍增長過程，一方面為雨滴碰并增長提供充沛的云水條件，即同時增強了冷暖云降水過程。地形對云的發展和降水的形成有明顯影響，當降低地形高度后，云水量減少，暖云過程減弱，同時也影響了霰粒子的增長過程。（高亮書，姚展予，賈爍，張沛，安琳，常倬林，桑建人，趙文慧，王偉?。?/p>

1.22 祁連山春季一次層狀云降水的雨滴譜分布及地形影響特征

祁連山是青藏高原東北部重要的生態屏障和冰川與水源涵養生態功能區，是黃河流域重要水源產流地，但針對該地區的云和降水過程研究很少。本文利用祁連山地區11個 Parsivel2雨滴譜儀的觀測數據，研究了祁連山地區春季一次層狀云降水過程的雨滴譜分布及地形影響特征。此次降水過程主要受短波槽影響，降水時空差異較大。雨滴譜觀測數據表明，此次降水過程的雨滴等效直徑（Dm）較小，雨滴譜數濃度（NT）與Dm隨海拔高度升高分別呈增加和減小的趨勢，低海拔站點lgNw（Nw為雨滴譜截斷參數）和Dm分布有著明顯的層狀云降水特征，而整個祁連山地區在同樣Dm下有著更高的Nw。低海拔站點由于碰并和小雨滴的蒸發，因此有著更少的小雨滴（＜1 mm）和更多的大雨滴，而高海拔站點由于距離云底較近或位于云內，云滴尺度小且濃度大，Dm隨R（R為降水強度）增大變化趨勢不明顯。M-P分布和Gamma分布在低海拔站點的擬合效果要優于高海拔站點，相較于Gamma分布，M-P分布對高海拔站點的小雨滴和大雨滴濃度有一定的高估和低估，因此更適用于高海拔站點雨滴譜的描述。對比于低海拔站點，高海拔站點的μ-λ（μ、λ分別為Gamma分布的形狀參數和斜率參數）關系與相關研究的結果較為接近，但在λ較?。ǎ?0 mm?1）時擬合結果較為接近。受海拔高度與云底的相對位置和地形的影響，祁連山地區的Z-R（Z為雷達反射率因子）關系與其他地區或研究有著較大的區別。（程鵬，常祎，劉琴，王研峰，李寶梓，陳祺，羅漢）

1.23 華北地區一次氣溶膠與淺積云微物理特性的飛機觀測研究

2014年8月15日，山西省人工降雨防雹辦公室在山西忻州開展了氣溶膠和淺積云的飛機觀測，本文利用機載云物理資料，詳細分析了華北地區氣溶膠、云凝結核（CCN）和淺積云微物理特性及其相互影響。主要結論有：（1）此次過程的邊界層高度約為3600 m，不同層結情況下，0.1～3 μm尺度范圍內的氣溶膠粒子濃度Na、有效直徑Da和CCN數濃度的垂直廓線明顯不同，近地面Na可達2500 cm?3。（2）CCN的主要來源為積聚模態、愛根模態或者核模態的氣溶膠顆粒，0.2%過飽和度下，氣溶膠活化率（AR）在各高度層的結果變化不大；0.4%過飽和度下，AR隨著高度增加而降低。（3）后向軌跡模式分析表明，2 km以下的氣溶膠主要來自于當地城市排放，由細顆粒污染物組成；2 km以上的氣溶膠主要來源于中國西北和蒙古地區的沙漠，由亞微米沙塵組成，溶解度相對較低，可作為潛在的冰核。（4）本文細致分析了兩塊相鄰淺積云（Cu-1 和 Cu-2）的云物理特性。Cu-1云底高度約4500 m，云厚約600 m，云體松散，夾卷較多；云中液態含水量（LWC）基本保持在0.5 g/m3，云粒子濃度Nc平均值為278.3 cm?3，云滴有效直徑Dc整體在15 μm以內；毛毛雨滴粒子濃度最大值為0.002 cm?3，云中幾乎無降水粒子；粒子譜寬隨著高度增加而增大，主要集中在30 μm以內。Cu-2云底高度約3900 m，云厚約1200 m，云體密實；云中過冷水豐沛，LWC有多個超過1 g/m3的區域，云頂附近出現冰晶，云中粒子從凝結增長狀態直接進入到混合相態；積云內部粒子水平分布不均，同一高度Nc相差較大，最大可達1240 cm?3。Dc隨著高度增加而增大；粒子譜寬隨著高度增加而拓展，最大可達1100 μm，譜型由單峰向多峰轉變；降水粒子和冰晶圖像大多為霰粒子、針狀和板狀。（蔡兆鑫，蔡淼，李培仁，李軍霞，孫鴻娉，楊怡曼，任剛，高欣）

1.24 祁連山一次地形云降水微物理特征飛機觀測

祁連山是我國西北地區重要的生態屏障，地形云是祁連山主要降水云系，加強對祁連山云微物理過程的認識，對科學有效開展人工增雨作業、改善生態環境具有重要意義。利用2020年8月29日祁連山一次地形云降水過程的飛機觀測數據，研究祁連山地區夏季云降水過程的微物理特征。此次降水過程云系呈明顯的分層結構，云底高度為4000 m，整層含水量較豐富，云水大值區出現在4500～5300 m高度，與云滴高濃度區對應，云水含量主要由粒子直徑為15～20 μm的云滴粒子貢獻。小云粒子和大云粒子平均濃度分別為7.54 cm-3和0.86 cm-3，有效直徑平均值分別為11.02 μm和198.11 μm,呈現出濃度小、直徑大的特征。云系翻越祁連山過程中南北坡云微物理特征有明顯變化，北坡（背風坡）粒子濃度、直徑和液態水含量明顯大于南坡（迎風坡）。祁連山地區不同高度小云粒子譜呈單峰型分布，Gamma分布可較好擬合直徑小于50 μm的云滴譜，直徑大于50 μm的云粒子譜更符合冪指數分布。凝華和聚并是冰相層冰雪晶的增長機制，混合層冰晶增長以貝吉龍過程為主，并伴有凇附和聚并生長。（程鵬，羅漢，常祎，甘澤文，張豐偉，劉維成，陳祺，冒立鑫）

2 關鍵技術研發與業務應用轉化

2 Key technology development and application

2.1 FACT: an air-ground communication framework for seeding quality control of aircraft

A new type of air-ground communication application framework named FACT (framework for airground communication technology with weather-modification aircraft) is presented to track and command weather-modification aircraft to perform ideal cloud seeding. FACT provides a set of solutions from three perspectives, namely, onboard, onground and air-to-ground, with the core purpose of solving the problems of the rapid exchange of information, contract analysis and identifying potential seeding areas when flight plans and meteorological conditions change. On board, the observed data are processed centrally and transmitted downward through air-to-ground communication. The real-time application and sharing of aircraft detection data are strengthened on the ground, and potential areas of operation are automatically identified based on ground data. The communication between the air and the ground achieves a technical breakthrough by realizing double satellite links, adaptive data transmission and VPN channel encryption. Additionally, an application based on FACT is designed and implemented for the real-time command of weather-modified aircraft. This approach has become the key air-to-ground communication system support for more than 40 Chinese aircraft and the big data service support center of airborne data to ensure improved operation of weather-modification aircraft in China.（Li Dequan, Li Jiming, Zhou Xu, Hu Jinrong, Wang Xin, Duan Jing）

2.2 Seasonal variations of aerosol number concentration and spectrum distribution in Nanjing

In this paper, the diurnal variations and seasonal variations of the aerosol spectrum distribution, as well as their correlations with meteorological factors in Nanjing in different seasons, are analysed. The results show that the number concentration of ultrafine particle in size of 0.01?0.1 μm accounts for over 60% of the total particle concentration in each season. The Aitken mode (AIM) particles dominate the changes of aerosol in Nanjing, which are mainly from traffic sources. Both local emissions and external transportation make important contributions to the air pollution in Nanjing. The southerly and easterly airflows are conducive to the accumulation of pollutants. The number concentrations of the AIM and Accumulation mode (ACM) particles decrease with the increasing wind speed, while the variation trend of the Nucleation mode (NUM) particles is opposite. The removal efficiency of precipitation for the ACM particles is much lower than that on the other three modes.（Jiang Qi, Wang Fei, Ying Chun, Zhu Bin）

2.3 Increasing cloud water resource in a warming world

Under global warming, terrestrial water resources regulated by precipitation may become more unevenly distributed across space, and some regions are likely to be highly water-stressed. From the perspective of the hydrological cycle, we propose a method to quantify the water resources with potential precipitation capacity in the atmosphere, or hydrometeors that remain suspended in the atmosphere without contributing to precipitation, namely cloud water resource (CWR). During 2000–2017, CWR mainly concentrates in the middle-high latitudes which is the cold zone of the K?ppen classification. In a warming world, CWR shows a significant increase, especially in the cold zone. Climate change with Arctic amplification and enhanced meridional circulation both contribute to the change of CWR through influencing hydrometeor inflow. By studying the characteristics of CWR and its influencing mechanisms, we demonstrate a potential for human intervention to take advantage of CWR in the atmosphere to alleviate terrestrial water resource shortages in the future.（Cheng Jingya, You Qinglong, Zhou Yuquan, Cai Miao, Nick Pepin, Chen Deliang, Amir AghaKouchak, Kang Shichang, Li Mingcai）

2.4 層狀云催化宏微觀物理響應的數值模擬研究

層狀云系是進行人工增雨開發利用空中云水資源的重要對象，增雨作業需要有科學可行的技術指標來指導實際作業的科學實施，而合理準確評估人工增雨作業的效果也是需要解決的重要課題，通過數值模式合理地仿真模擬實際催化作業的過程，進而研究增雨作業后云和降水的一系列宏微觀特征的變化及其機理，是建立和改進催化作業技術的必要途徑，也是評估實際人工增雨作業效果的有效手段。本文使用三維中尺度冷云催化模式對2014年4月15日河北省一次層狀云降水的飛機催化作業過程進行了仿真模擬，力圖對實際作業過程進行合理再現，通過對模擬結果的分析，研究飛機播撒的AgI（Silver iodide）催化劑在空中的擴散傳輸特征，分析催化對云和降水宏微觀特性的影響，并對此次飛機催化作業的增雨效果進行評估。研究結果表明：播撒的AgI催化劑煙羽擴展的水平尺度可達數十公里以上，垂直方向上，大部分AgI粒子則主要集中在作業層上下約1 km的厚度范圍內，AgI粒子的向上輸送明顯強于向下的輸送；催化后云中的冰晶和雪粒子明顯增加，導致催化模擬前期的霰增長受到抑制，之后隨著霰碰并雪過程及零度層附近冰相粒子淞附過程的增強，云中霰的總量逐漸增加；催化作業后，催化云的雷達回波強度有明顯增強，且隨時間變化表現出不同的結構特征；催化導致地面降水出現先減少后增加的時間變化特征，催化后3 h，作業影響區向作業區下游擴展100 km以上，總體呈現減雨—增雨的區域分布特征；數值模擬評估表明，整個評估區內的凈增雨量達到3.6×107kg，平均增雨率為1.1%，暖層霰粒濃度和尺度的增加是降水增加的主要原因。由于作業目標云系的催化條件一般，而播撒的AgI劑量偏大，造成增雨作業效果偏低。（劉衛國， 陶玥， 周毓荃）

2.5 一次對流云人工消減雨作業云條件預報和作業預案合理性分析

為做好固定目標時段和區域的人工消減雨作業，利用云降水顯式預報系統（CPEFS_V1.0）對云系性質和結構、移速移向及演變、降水機制等云條件進行預報。預報結果顯示：2017年8月8日影響呼和浩特的云系性質為分散性對流云，具有冷暖混合云結構，云中上升氣流強，對流單體水平尺度約幾十公里，生命史1.5～3 h，云頂高度約10 km、云底高度約3 km，0 ℃高度約為4.3 km；微觀方面冰相水凝物雪、霰含量高，暖區云水含量少，云中過冷水含量最大達0.7 g/kg，過冷水豐沛區域冰晶數濃度低，以冷云降水為主。初生在呼和浩特特定防護區西北方向的對流云團快速發展東移南壓影響核心保障區，移速30～40 km/h。衛星、雷達等實況監測顯示8日的云系為分散性對流云，預報對流云的生成時間比實況偏晚1～2 h，移向與實況一致，移速偏慢10～20 km/h。在5400 m高度處（-8 ℃），機載云物理探測的液水含量最大為0.6 g/m3，預報與實況接近。根據預報的云系條件制定作業預案指出，在核心保障區的偏西北方向50～30 km處進行重點布防，適宜在5.1～7.0 km高度處實施AgI過量催化，8日上午飛機在第一道防線的弱回波區開展探測作業，地面作業集中在第三道防線對流云初生階段實施過量播撒，以達到消減雨作業的目標。根據預案，提前24 h在核心保障區偏西北方向的第三道防線增設了5個地面移動作業點，這些作業點8日及時實施了消減雨作業?？傮w看來，此次云條件預報正確、預案制定合理，及時為外場實施消減雨作業提供了支撐。（史月琴， 劉衛國， 王飛， 高揚）

2.6 基于飛機真實軌跡的一次層狀云催化的增雨效果及其作用機制的模擬研究

層狀云降水效率通常較低，但卻具有較高的云水資源開發潛力，是人工增雨作業的重要對象。隨著中國南方地區生態改善、水庫增蓄、抗旱等社會需求的增加，針對這些地區降水云系的人工增雨研究顯得愈發重要。使用三維中尺度冷云催化模式，對2018年10月21日湖北省一次層狀云飛機人工增雨作業過程進行了數值模擬研究，并將模擬結果與衛星、降水和機載云物理觀測數據進行了對比。模式合理地模擬出了云和降水的主要宏、微觀特征，觀測和模擬結果均顯示作業云區具有較好的冷云催化條件，在此基礎上，按照實際作業中的飛機播撒軌跡，完整地模擬了此次催化作業過程。對數值模擬結果的分析表明：凝結凍結核化和凝華核化是碘化銀催化劑的主要核化方式；90%以上碘化銀粒子的局地活化比為0.01%～2%，平均活化比為0.07%～0.27%；云系降水是由冷云降水和暖云降水兩種機制共同作用的結果，催化作業使兩種降水機制均有增強，增雨效果明顯；催化后4 h，整個評估區內的累計凈增雨量為2.12×108kg，局地增雨率為?51.1%～306.7%，區域平均增雨率為8.1%；催化作業也使部分地區出現減雨，主要是由于催化過程中的潛熱釋放引起過冷層動力場擾動，一部分云區的上升氣流減弱，從而導致降水粒子的成長減弱，地面出現減雨；在過冷云區，碘化銀核化使冰晶濃度升高，導致冰晶—雪、雪—霰的轉化過程增強，雪、霰粒子總量增加，更多的雪、霰粒子從冷區落入暖區，在暖區上層產生更多的大雨滴，從而使暖區的云雨粒子碰并過程增強，最終地面降水增加，這是此次催化作業導致增雨的主要微物理鏈條。（劉衛國， 陶玥， 周毓荃， 黨娟， 譚超， 高揚）

2.7 飛機積冰的云層特征個例分析

利用衛星、雷達、探空、飛機等觀測資料和NCEP再分析資料，以及數值模擬結果，對 2016年3月8—9日我國安慶地區的云系特征和飛機積冰氣象條件進行了分析。結果表明，此次飛機積冰發生在寒潮天氣背景下，強冷空氣造成鋒面逆溫。實測飛機積冰現象出現在對流降雨結束后的層積云層頂部，積冰高度對應高空鋒區逆溫層底部，云頂高度約3.4 km，云頂溫度-10 ℃，無降水和雷達回波，云中主要為過冷水，豐沛時段飛機觀測過冷水平均值為 0.36 g/m3，基本無冰相粒子。當云頂高度再度抬升，冰相粒子增多時，過冷水含量減少，不利于積冰現象發生。CPEFS模式模擬出了與實測比較一致的云宏微觀結構。（孫晶， 蔡淼， 王飛， 史月琴）

2.8 新疆春季兩次直升機積冰氣象條件分析

利用衛星、雷達、探空、地面等觀測資料和NCEP再分析資料，以及數值模擬結果，對2018年3月新疆昌吉地區兩次飛機積冰探測試驗過程的云系特征和積冰氣象條件進行了分析。 結果表明，兩次直升機積冰過程影響系統分別為500 hPa低渦和500 hPa淺槽，地面有冷鋒配合。積冰時段處于低渦系統發展前期階段和低槽系統發展中期階段。積冰云層均為中低云云層，云頂高度為4 km，云頂溫度為-15～-25 ℃，云底高度為1.5 km，云層厚度為1～3 km，光學厚度大于12，雷達回波特征不明顯，無回波或者回波強度在10 dBz以下。3月27日淺槽鋒面過程云頂有逆溫。CPEFS模式模擬云微觀結構表明，積冰云層是以過冷水為主，冰相粒子含量很少。 根據直升機特性修改后的CIP初始積冰潛勢算法較好地體現了這兩次層積云飛機積冰特征，對于穩定性云層的積冰潛勢具有指示意義。結合飛行速度等參量計算的積冰強度與實況基本吻合。（孫晶， 譚超， 周毓荃， 劉政， 黃珺， 王澤林）

2.9 DMT機載云粒子圖像形狀識別及其應用

利用機載云粒子探測設備入云進行觀測是目前獲取云粒子微物理特征最直接有效的手段。國內已有多家單位引進美國DMT公司的云粒子圖像探頭CIP。由于其配套軟件不能輸出逐個粒子的詳細信息，在很大程度上限制了對云粒子圖像探測數據的深入挖掘和分析?；诮馕隽Ｗ訄D像原始數據，對粒子圖像數據進行質量控制，并根據粒子形狀幾何特征將粒子形狀分為8類（微小、線狀、聚合狀、霰狀、球狀、板狀、枝狀和不規則狀）。利用2018年12月至2019年3月河南省3次冬季航測獲取的灰度CIP探測數據，分析云粒子形狀及各形狀粒子面積的統計特征，并對比基于不同形狀粒子的質量—尺度關系與將所有粒子視作球形液滴計算所得的粒子水凝物含量，發現后者超過前者約1個量級。（張榮， 李宏宇， 周旭， 李昊， 胡向峰， 夏強）

2.10 一次東北冷渦結構及云系特征分析

利用ERA5逐小時再分析資料、FY-4A衛星反演云特征參量產品、逐小時地面降水資料，分析了2020年5月16—19日一次東北冷渦降水過程的環流形勢、熱力不穩定條件、水汽輸送及云系宏微觀特征。結果顯示，本次過程500 hPa低渦中心位于36°～48°N，對流層中高層至低層均有氣旋性環流，伴隨有地面氣旋，屬于深厚的中偏南渦，共維持了6 d。18日遼寧東部出現區域性暴雨，24 h降水量超過100 mm的站點有15個，最大雨強達到了43.4 mm/h，暴雨區出現在冷渦成熟階段，位于冷渦后部偏北氣流影響下，來自熱帶低壓東側西南低空急流輸送的水汽與冷渦東南部的水汽輸送合并，成為了暴雨產生的必要條件。降水強度大于6 mm/h的區域，K指數基本都大于35 ℃，且整層都有較強的垂直上升運動。冷渦云系云頂高度為4～9 km，靠近冷渦中心的渦旋狀云系云光學厚度大于30，云層水凝物含量豐富密實，屬于冷暖混合云，降水主要出現在這些區域；遠離冷渦中心的區域云系光學厚度小于20，云層松散屬于高層冰云，地面基本無降水。（史月琴， 周毓荃， 戴艷萍）

2.11 SPEC機載云探測系統及其云物理研究進展

在綜合介紹我國機載云探測系統的發展歷程、應用情況和優缺點的基礎上，對新一代機載云探測系統SPEC的系統組成、探測原理、探測方法和探測范圍等進行了詳細說明，并探討了近年來國內外相關研究進展。隨著科學研究人員對云探測精細程度、準確度要求的日益提高，以往使用的粒子觀測系統（PMS）等云探測系統已無法滿足一些科學試驗的需求；SPEC與很多其他云探測系統相比，在精密程度、探測粒子的信息量、分辨率等方面具有很大的探測優勢，這對于云物理更深入的研究是非常重要的。國外研發并應用SPEC系統已有幾十年的時間，而我國近年開始引進并越來越多地使用這套探測系統來探究云的宏微觀物理特性，這必將使得對云物理的理解更加深入。（劉思瑤， 趙傳峰， 周毓荃）

2.12 基于Ka波段云雷達的六盤山頂云特征分析

本文利用寧夏六盤山氣象站2017年9月至2018 年8月的Ka波段云雷達觀測資料，統計分析了六盤山頂不同云的出現頻率及宏觀特征。結果發現：六盤山頂云出現頻率最高值出現在7月，為61%，最低值出現在12月，為26%；按云層數劃分，六盤山頂出現的云主要以1層云、2層云及3層云為主，相對總云的月平均出現頻率分別為68%～86%、14%～27%及0.4%～4.8%；按云底高度及云層厚度劃分，六盤山頂低云、中云、高云及直展云相對總云的月平均出現頻率分別為29%～53%、14%～58%、6%～22%及2%～20%。云底高度在冬春季節高于夏秋季節， 云頂高度在夏秋季節高于冬春季節，云層厚度在1.6～3.6 km 之間，年變化特征與云頂高度類似。整體來看，春、夏、秋季云厚在白天大于夜間，冬季云厚在夜間大于白天，其中夏、秋季云厚日變化特征較為明顯。（田磊， 桑建人， 姚展予，常倬林， 舒志亮， 曹寧）

2.13 基于微波輻射計的寧夏六盤山西側大氣水汽變化特征

采用隆德氣象站2 a德制微波輻射計與同期1 h降水量資料，利用統計法分析了六盤山脈西側大氣水汽含量以及云液態水含量的時間分布特征，并分析了92次不同降水性質、不同降水量級的降水個例，得到降水前躍增時間的變化特征。剔除降水背景結果統計表明：（1）六盤山西側大氣水汽含量和云液態水含量有明顯的季節變化，其中夏季是大氣水汽含量最多的季節，平均為23.44 mm，占年均水汽含量的47.7%。（2）大氣水汽含量和云液態水含量日變化呈—谷—峰分布，春、夏、秋三季均在午后出現最大峰值，冬季在11:00出現峰值；大氣水汽含量低值區春、夏、秋季出現在日出前后，冬季出現在22:00。（3）87.0%的降水個例在降水發生之前大氣水汽含量都在12.00 mm以上，且其值隨著降水的量級增大而增大。（4）降水前云液態水含量發生明顯躍增現象，春、夏季表現強，根據降水性質及降水量級不同，降水前躍增時間也不同。研究結論對把握人影作業時機具有一定的參考價值。（林彤， 桑建人， 姚展予， 舒志亮， 田磊， 曹寧， 常倬林）

2.14 利用FY-4A衛星光學數據對中國近地面PM2.5濃度的估算和檢驗分析

對FY-4A衛星的氣溶膠光學厚度（AOD）產品進行檢驗，并根據衛星相關觀測資料，通過改進后的PMRS方法，反演得到中國近地面PM2.5質量濃度網格化分布。結果表明，FY-4A衛星反演不同站點AOD與地基觀測網（AERONET）觀測結果吻合較好，但存在一定的低估或高估現象，相關系數區間為0.54～0.87。將細粒子比（FMF）以0.4為界進行劃分，FMF＞0.4時，擬合結果較FMF≤0.4時更接近于AERONET觀測結果；但FMF≤0.4時，衛星反演的AOD穩定性優于FMF＞0.4時。通過引入AOD的大小，改進FMF＞0.4時對細粒子柱狀體積消光比（VEf）的估算算法，并通過改進后的PMRS方法對中國近地面PM2.5濃度進行逐時反演，其反演結果和地面觀測結果相關較好，其中，烏魯木齊、石家莊和徐州觀測點的相關系數均高于0.7，但數值上仍存在高估或低估，誤差結果由多種因素決定?？臻g分布中，衛星反演的中國2019年近地面PM2.5濃度月均值與近地面觀測的結果有較好的對應關系，二者逐月演變趨勢基本一致，基本可以反映出中國近地面大氣細粒子的空間分布，特別是秋、冬季京津冀周邊區域、汾渭平原等污染高值區均與地面觀測對應較好。（江琪， 迎春， 王飛， 張天航， 何佳寶， 桂海林，張碧輝， 徐冉）

2.15 崇明東灘濕地與上海城市氣候特征對比分析

基于2010—2019年崇明東灘濕地與同期的上海近海臺站、崇明氣象站及市區氣象站的溫度、濕度、降水觀測資料，采用時間同步對比方法，分析了崇明東灘濕地與上海城市不同地區的氣候特征。結果表明：東灘濕地由于其地理位置特殊，與上海其他臺站比，日最高氣溫最低、春夏氣溫升幅最小，日最低氣溫接近或高于近海臺站和崇明城鎮的日最低氣溫，僅低于中心城區的日最低氣溫，濕地不易升溫、也不易降溫；由于東灘濕地下墊面性質及周圍環境與城市其他臺站的不同，沒有城市熱島效應、阻礙效應引起的增雨，中雨以上降水概率明顯小于其他各站的降水概率，暴雨概率及強降水次數比其他各站分別少68%～75%和70%～81%，表明東灘夏季雨日少于其他各站的雨日，但秋冬季雨日比其他各站多18%～40%，這也是東灘濕地總雨日多的主要原因；東灘濕地不但縮小晝夜溫差還縮小晝夜濕差，尤其濕地能降低雨強，致使有雨日逐年平均相對濕度反而比上海其他各站的小。（賀芳芳， 毛卓成， 姚展予， 許建明， 彭麗）

2.16 臨沂市區冬季大氣污染物的特征解析

基于2018年冬季臨沂市區4個國控環境空氣自動監測子站的SO2、NO2、CO、O3、PM2.5和PM10小時濃度數據，研究了臨沂市區大氣污染物的特征。結果表明：PM2.5和PM10污染最為嚴重，其次是NO2和CO，而SO2和O3污染較輕；SO2、CO和O3空間差異顯著，NO2、PM2.5和PM10空間差異不顯著。日變化特征分析發現，SO2、CO和PM10呈雙峰型，NO2呈單谷型，O3呈單峰型，PM2.5呈一峰二谷型分布。O3與其他大氣污染物不同，清潔天空氣質量較好，強太陽輻射會促進光化學反應生成更多O3。氣團后向軌跡聚類分析結果顯示，臨沂市區冬季主要受近距離的氣團輸送影響，同時也受到來源于蒙古國的高空遠距離沙塵輸送影響。（王璐， 溫天雪， 周旭， 劉旭）

2.17 全球云水量氣候分布及變化趨勢特征分析

采用20世紀再分析版本2c數據集的云水量逐月再分析數據，通過數理統計方法，分析了1960—2014年全球、海洋和陸地上空云水量的分布和變化特征及其與水汽通量的關系。結果表明：（1）全球云水量空間分布不均，海洋高于陸地且比例約為4﹕3，中低緯海洋、陸地上空云水量變化趨勢分別為0.07 g/（m2·10a）和?0.04 g/（m2·10a），季節性差異主要體現于夏季在熱帶輻合帶和南半球海洋高，冬季在北半球海洋和南半球陸地高。（2）對比六大洲發現，云水量最高的南美洲有最快增加趨勢，為0.46 g/（m2·10a），同時云水量最低的非洲有最快降低趨勢，為?0.59 g/（m2·10a）。（3）中低層整層水汽通量散度場的輻合、輻散區和云水量的高、低值區相對應，云水量與水汽通量散度變化呈負相關（相關系數為?0.44），負相關關系在赤道附近的低緯地區顯著。本文揭示了在全球變暖背景下，大氣中云水量分布和變化的時空格局，為模式參數化和未來氣候預估提供參考。（程敬雅，游慶龍，蔡淼）

2.18 云解析人工影響天氣數值模式的改進、初步試驗和展望

基于WRF四維資料同化和預報技術，初步發展了針對我國西北地區云微物理和播云催化技術的云解析人工影響天氣模式系統（CR-WMM）。該模式耦合并改進了中國氣象科學院發展的微物理方案（CAMS-MP）和碘化銀（AgI）催化方案，并實現基于大渦模擬（LES）模式的飛機、地面煙爐等播撒源及毗鄰區域AgI粒子擴散的精細模擬方法。選取降水案例對CR-WMM資料同化功能、CAMS-MP微物理參數化和AgI的催化數值模擬方案進行測試和評估，驗證了該系統的資料同化能力、微物理參數化和AgI催化數值模擬方案的可靠性。CR-WMM具備連續同化常規和加密氣象觀測，特別是針對云微物理過程的新型衛星、云雷達和人工影響天氣外場作業飛機和基地的特殊觀測能力，能生成全面、精確的云和降水熱力、動力和微物理分析場，支撐云和降水過程及云催化技術的理論研究及優化人工播云方案輔助決策。并提出為達到這一目標，CR-WMM模式在未來5～10年應集中攻克的5個方面的科學難題。（劉玉寶， 丁秋冀， 史月琴， 方春剛， 段婧， 樓小鳳， 李萍， 霍朝陽， 周永波， 王昊亮， 景曉琴， 王新， 陳添宇， 陳寶君， 李集明）

2.19 基于時域對象的網格降水預報的追蹤診斷分析

檢驗和評估模式降水預報的時間和位置偏差對提高降水預報準確率有重要意義，而傳統點對點的檢驗方法對此無能為力?；?018年和2019年6—8月歐洲中期預報中心（ECMWF）降水預報資料，利用面向對象時域診斷分析工具（MTD），追蹤模式降水預報對象的生命周期、初生、消散等預報表現。研究表明：（1）個例分析顯示，時域診斷分析工具MTD能夠很好的從三維降水場中提取降水對象，進而刻畫降水對象的生命周期及開始結束時間，對客觀描述降水對象的時間偏差具有獨特的優勢。（2）低閾值條件下模式預報能很好地描述降水對象的空間分布，不足在于觀測降水對象較模式預報明顯偏多；隨著降水閾值增大，預報與觀測降水對象的空間頻次呈現出顯著差異，表明模式對強降水的位置預報仍然需要改進。（3）采用最小卷積半徑和降水閾值定義降水對象，觀測和預報場中80%的降水對象生命周期小于15 h，且生命周期隨著降水閾值和卷積半徑的增大而減小。（4）三維對象追蹤顯示，預報對象的持續時間較觀測偏短，移動速度較觀測整體偏慢。（張宏芳，潘留杰，盧珊，巨曉璇，史月琴）

3 項目進展和觀測試驗

3 Project progress and observational experiments

3.1 云水資源評估研究與利用示范

云水資源評估研究與利用示范研究取得如下進展：（1）基于大氣水循環過程和云物理過程及大氣水分收支平衡方程，提出并完善云水資源及其11個組成量和12個特征量的概念和計算式。（2）構建多尺度三維云場診斷技術體系，建立并優化云水資源觀測診斷和數值模擬兩套定量估算方法，研發云水資源評估系統（V1.0），實現中國和全球近20年1°分辨率、全球近60年2.5°分辨率的云水資源診斷評估及華北示范區近5年3 km分辨率的云水資源數值精細評估，并開展對比驗證。（3）利用近20年中國云水資源評估數據集，研究得到中國不同人工影響天氣分區和關鍵典型水文流域（如黃河流域、淮河流域）的云水資源特征，利用3 km的數值評估結果，揭示華北區域的云水資源特性，利用全球云水資源評估數據集，研究得到全球云水資源的時空分布特征和變化規律。（4）在兩個示范區建立并優化固定目標區云水資源開發技術體系，探索發展北方層狀云飛機增雨和南方對流云地面增雨優化的方案設計及效果評估方法；建立空陸耦合云水資源開發利用全流程技術體系，攻關云水資源預報及開發效果預估等關鍵技術環節，并應用于重大活動保障。

3.2 人工影響天氣技術集成綜合科學試驗與示范應用

人工影響天氣技術集成綜合科學試驗與示范應用項目開展了3次華北多機聯合觀測，取得星—空—地聯合觀測數據集2套；完成一種浸潤凍結機制冰核測量裝置（FINDA）的搭建與應用，其試驗結果與國際上其他學者的結論一致。梳理南方各種類型對流云個例21個；分析祁連山地形影響下的云降水演變特征與機理以及地形云降水微物理特征與降水機制，結果表明不同類型強降水的形成機制及物理量條件各有差異，地形對降水的影響效應也各不相同，揭示地形云凝華和聚并是冰相層冰雪晶的增長機制，混合層冰晶增長以貝吉龍過程為主，并伴有淞附和聚并生長；利用DBSCAN聚類算法及Hough變換，提出一種對雷達線狀或帶狀颮線的自動識別方法，并用5次颮線天氣過程檢驗DBSCAN算法和Hough變換的合理性和有效性；初步試驗結果認為燃氣炮增雨作業有效果，但還需要開展更多的外場試驗和試驗分析?；陲w機觀測檢驗微物理結構模擬，將各微物理方案模擬的IWC、冰相粒子譜、粒子數濃度和M-D關系進行了對比分析，給出各微物理方案在模擬能力上的各自優勢。

3.3 新一代人工影響天氣數值模式系統研發

新一代人工影響天氣數值模式系統研發工作取得如下進展：（1）在WRF中建立全新三參數云物理方案并開展批量預報試驗，對6月份一個月的預報結果表明，該方案可以有效預報不同云降水過程，在模式積分時間步長方面有待改進。（2）在WRF4.2動力框架中耦合了CAMS雙參數云微物理方案，利用1 km水平分辨率開展不同區域、不同時間的積層混合云、對流云、層狀云等多個例模擬研究，模式運行穩定，模擬的降水、云系結構特征及演變與衛星、雷達、機載云物理探測實況相符。（3）開展AgI催化方案的編制及與WRF模式中CAMS云方案的耦合試驗。（4）采用分析逼近Nudging同化方法，開發雷達資料反演的水成物場及對應的潛熱進行同化的方案，基于WRF模式實現對雷達資料的實時同化和模擬應用，個例對比試驗表明，同化后對于模擬的降水落區范圍比無同化有明顯改善，更接近實況觀測。（5）探索了面向對象檢驗（MODE）方法在云場檢驗方面的適用性，開展了不同檢驗方案（格點、鄰域、對象）對預報云場的檢驗適用性研究，并對夏季的云場預報結果進行檢驗應用。

3.4 新型催化劑研發

組織召開新型催化劑研制課題2021年度工作會議，課題組開展了膨脹云室物理模擬試驗能力的測試和初步試驗，進一步完善云室系統的云霧參數監測系統；開展了表明活性物質作為暖云催化潛力的模擬試驗；開展了華北污染背景的實驗室模擬試驗研究（70 m3膨脹云室）；開展了納米催化劑的擴散云室模擬試驗研究；討論研制了3中不同吸濕性暖云催化劑的試驗配方，完成工廠加工壓制和工廠性能測試，近期將送北京實驗室開展模擬試驗，進而篩選出效果較好的暖云催化劑型。完成發表論文1篇，申請發明技術專利1項，已進入實質性審查階段，申報實用新型技術專利3項，其中2項得到授權，1項受理中。1項氣象行業標準預研究項目通過驗收。

3.5 貴州防雹外場觀測試驗

2021年4月，首部用于人工防雹觀測的X波段雙偏振相控陣雷達在貴州威寧防雹基地建成。2021年5月13日，人工影響天氣中心組織開展國家（貴州）防雹外場科學試驗實施方案論證會。5月27日召開2021年國家（貴州）防雹外場試驗啟動會，人工防雹外場試驗正式啟動。試驗持續到9月底結束，基于X波段雙偏振相控陣雷達共觀測防雹個例18次，收集了多種掃描方式（體掃、扇掃和RHI掃）的防雹觀測資料，為貴州威寧冰雹結構特征分析和防雹效果檢驗提供了直接的外場觀測資料，目前正對觀測資料進行整理分析。本次觀測通過利用高時空分辨率的相控陣雷達資料清楚觀測到貴州威寧冰雹云的發展演變過程和垂直結構特征，發現威寧冰雹發展迅速，穩定少動；雹云強回波首先出現在空中，然后向下發展加強；雹云在成熟期主要呈傾斜垂直結構，有明顯的有界弱回波區，空中存在冰雹特征。高時間分辨率的相控陣雷達能對防雹效果進行檢驗，從相控陣雷達可以看到高炮作業后強對流的雷達回波減弱、強回波面積有所減少，特別是高炮作業量增大后，防雹作業效果比較明顯。

3.6 廬山云霧降水外場觀測試驗

2021年，對廬山云霧降水外場觀測試驗進行了重新部署，開展了秋冬季外場試驗。在2020年外場試驗方案的基礎上，根據新設備補充情況和2021年的試驗需求，不斷完善試驗方案和實施方案，編寫完成了《2021年國家（廬山）云霧物理試驗基地外場觀測試驗方案》。2021年9月28—29日聯合江西省氣象局組織和召開了2021年國家（廬山）云霧物理試驗基地外場觀測試驗啟動會，秋冬季外場觀測試驗正式啟動。會后與江西省氣象局聯合編寫完成《廬山云霧物理試驗基地2021年外場試驗工作方案》，作為工作指南。此次試驗布局為以山上、山下的聯合梯度觀測，以及山上不同地點的同要素對比觀測，依此開展包括秋冬季大氣與氣溶膠背景特征、云宏觀及微物理特征研究。根據觀測要求，新增2臺霧滴譜儀、冰核采樣器、云凝結核儀、PCASP-X2、霧水采集器等觀測設備，并將云霧站單一的觀測點擴展到云霧站和仰天坪兩個觀測點，在仰天坪調度和布設了自動氣象站、霧滴譜儀、能見度儀、微雨雷達、云凝結核儀、冰核采樣器和顆粒物儀等觀測設備。2022年1月9日，廬山秋冬外場試驗基本完成年度觀測任務（10月1日至1月9日）。此次試驗10月初開始，11月10日基本完成兩個主要觀測點（云霧站、仰天坪）的設備調試和部署，12月8日完成梯度觀測部署（廬山市氣象局），所有設備部署地點均按試驗方案部署完成后，一直進行持續的加強觀測。初步統計，捕捉重點天氣過程約13次，包括云霧（最多）、降雨（1次）、降雪（3次）、凍雨（1次）過程。采集包括霧滴譜儀、微雨雷達、微波輻射計、云高儀、能見度儀、云凝結核計數器、顆粒物儀、自動站等數據資料約670 G；霧水樣本（46份）；冰核膜采樣樣本（95份）。在山上兩個站點（仰天坪和云霧站）重點開展了云霧、降水對比觀測；此外，在仰天坪開展了冰核、云凝結核加強觀測，在云霧站開展了云霧過程的霧水采集觀測；同時實現了山上、山下云宏觀特征的梯度對比觀測。獲取了多次包括凍雨等特殊天氣過程的觀測數據。

3.7 數據集建設

廬山云霧觀測數據集建設進展。4月邀請參與過廬山觀測的老專家協助解決歷史數據中字跡不清楚和記錄方法等問題，重新翻閱了紙質版歷史資料，經過4個版本的更新，已經完成歷史數據集的數字化工作。7月初經商議確定現代數據集除了csv文本格式，新增NetCDF格式數據集，確定了NetCDF格式確定數據錄入信息和結構存儲方式。9月在針對nc格式的專家咨詢會中進一步確定了存儲的細節并咨詢疑問，已經完成兩個版本的csv格式和NetCDF格式的數據樣本。合理利用人影數據標準編碼規范的同時，調整了地基特種觀測數據的編碼格式，改進和更新了數據集的存儲和質控方案。經過一年多的建設，目前對于歷史觀測資料，已經完成所有資料的歸整、查閱、補充掃描、內容訂正等工作，完成了歷史數據集的數字化。對于現代觀測數據，已經完成數據的質量控制，并多次完善現代數據的編碼和存儲方案，階段性的推進數據集建設，形成現代數據集樣本，并正在開展數據質量評估。廬山云霧觀測數據集已基本建成。同時，建設期間初步形成了一套較完整的《人工影響天氣試驗地面特種觀測資料集數據文件編碼和存儲格式規范（草稿）》。

飛機觀測數據集建設進展。優化改進了飛機數據處理系統，完成國家級飛機探測數據集建設項目的平臺改造；初步建立了一套飛機數據集，完成2017—2020年國家級高性能飛機所得探測數據的處理和成集工作，并提供中心使用；梳理了一批典型探測個例，初步形成了一套飛機數據質控流程，為中心所承擔的重大活動保障、重要應急保障以及重點科研項目所得的飛機探測數據提供質控和產品制作服務；完成了用戶手冊、工作報告、技術報告等文檔。

3.8 云霧物理環境重點開放實驗室開放課題

2021年度中國氣象局云霧物理環境重點開放實驗室開放課題分別在多源數據融合技術的人工影響天氣應用研究、冰雹云結構及成雹機理研究、山地環境氣溶膠—云霧特征及相互作用研究，以及人工增雨防雹火箭技術研究5個重點研究領域共資助11個課題，資助強度2～3萬元，總經費26萬元。受資助人員涵括人影業務部門、相關高校以及科研單位。

4 人工影響天氣現代化建設

4 Modernization of weather modification

4.1 西北區域人工影響天氣能力建設項目總體設計與實施

概要梳理了西北區域人工影響天氣能力建設項目總體設計的思路，歸納了設計中所重點考慮的3個技術系統和技術措施，總結了項目建設模式與經驗，可為后續區域人工影響天氣項目建設提供參考和借鑒。（李集明，陳添宇，陳寶君，顧青峰，殷占福，段婧，李宏宇，李德泉，方春剛，房文，尹憲志，李林，桑建人， 李抗抗）

4.2 “云+端”業務框架的西北人工影響天氣指揮應用系統綜述

簡要闡述了面向人工影響天氣業務深度融入“天擎”大數據云平臺需求，在西北區域首先采用“云+端”業務系統架構模式設計并實現新型的人工影響天氣指揮業務系統（SPACE-NW），為人工影響天氣各類業務提供綜合業務軟件支撐。該系統依托“天擎”基礎，提出具有普適性的人工影響天氣“云+端”下的“4C+ABC”框架，實現了人工影響天氣業務數據環境深度融入、產品分析與自動化制作與加工流水線的深度融入、資料分析與指揮業務流程與基礎氣象業務的深度融入。解決了人工影響天氣部門一段時期以來的資料采集渠道多樣、標準不統一、系統開放性不足、信息流轉渠道不暢等業務問題。該系統在西北區域率先部署試用，發揮省級人工影響天氣業務與“天擎”的深度融入的典型示范作用。（李德泉，李集明，田建兵，田顯，穆建華，李寶梓 ，白向東，李圓圓）

4.3 西北區域人工影響天氣試驗示范基地設計

西北人工影響天氣工程在西北地區選取重點區域建設人工影響天氣試驗示范基地，合理設計觀測儀器設備布局，建立了涵蓋中尺度水汽、風場監測、云降水宏觀場監測、云降水微觀場探測的大氣、云和降水宏微觀三維結構及濕熱力、動力綜合監測網；在基地科學設計外場試驗區，開展外場作業試驗，開展新型催化作業裝備和催化劑研發?；氐慕ㄔO能夠有效地促進我國人工影響天氣業務自主創新，為西北區域和全國人工影響天氣業務發展提供有力的科技支撐，提高作業效率和水平，提高西北區域人工影響天氣作業實際效益。目前該基地已基本完成觀測系統以及業務平臺建設，觀測資料已在研究試驗中得到有效應用。（方春剛， 段婧， 李圓圓， 李寶梓， 岳治國， 田磊， 田建兵， 黃山， 陳添宇， 陳寶君， 李集明）

4.4 西北人工影響天氣工程研究試驗設計與實施

西北區域人工影響天氣能力建設項目通過科學設計，創新運行機制，預期利用已有和本項目即將建設的裝備設施，通過有科學設計的專項研究，開展針對西北區域地形云的人工增雨（雪）試驗研究。在工程項目建設中設立研究試驗內容，旨在通過項目建設中同步實施試驗研究，充分體現科技支撐能力在工程項目中的重要作用。本文總結了西北區域人工影響天氣能力建設項目中研究試驗的設計和實施過程，依據建設經驗，提出提高工程項目效益的建議，為相關工程項目建設提供參考。（段婧，王自強，李圓圓，程鵬，常倬林，林春英，岳治國，史金麗，殷占福，陳寶君，陳添宇，李集明）

4.5 空中國王350增雨飛機改裝與集成設計

介紹了西北區域人工影響天氣能力建設項目（以下簡稱“西北人影項目”）建設的2架空中國王350國家級作業飛機（以下簡稱“西北空中國王飛機”）差異化和通用化的設計思路，以及西北空中國王飛機機載大氣探測系統、機載催化作業系統、空地通信系統改裝集成工作的所要遵循的原則、工作思路和初步方案。對后續人工影響天氣區域工程項目飛機改裝集成工作提供相應的技術支持。（高揚，李宏宇，殷占福，戴艷萍，陳添宇，李集明）

4.6 新舟60高性能增雨飛機機載任務系統集成設計

西北區域人工影響天氣能力建設項目設計建設的新舟60增雨飛機是集催化作業、云宏微觀探測以及實時通信與綜合集成顯示功能于一體的國家高性能人工增雨飛機，該飛機系統建設中充分汲取了前期東北區域國家增雨飛機研制成果與經驗，并在系統供電管理、催化作業能力、探測系統集成、衛星通信功能、設備系統和操作臺布局等方面進行了針對性設計改進，通過便捷操作實現對任務系統供電與各分系統的集中控制、綜合顯示、數據存儲共享，并且機載探測、催化、通信各分系統均采用雙重或多重備份設計，既保證了機載任務系統先進性設計，同時保證任務系統運行穩定可靠和各項功能的完整實現。（張驍拓，胡穎瓊，李宏宇，蘇海周，周旭，高揚，張榮）

4.7 陜西渭北果業區冰雹研究進展

闡述了開展陜西渭北果業區防雹技術研究試驗的重要意義，討論了渭北果業區冰雹研究在氣候、雷達回波、雹云探空、冰雹微物理、數值模擬和防雹效果等方面的進展，并對研究試驗中存在的問題進行了討論。這些研究加深了渭北冰雹形成過程的認識，對研究高效冰雹防御方法和提高冰雹防御效果有重要意義。（岳治國，陳寶君，王瑾，左愛文，李金輝，羅俊頡，朱榮增，花少烽，劉佩佩）

5 人工影響天氣重大應急與重大服務保障

5 Weather modification in support of major emergency response and major event service

面對持續時間長、影響范圍廣的南方冬春連旱，迅速響應、國省協同、空地聯合作業，全力做好抗旱增雨、森林滅火等重大應急服務保障。在日常業務發布的人工影響天氣模式預報和衛星監測云條件產品基礎上，針對重大活動保障和森林草原防滅火等應急人工影響天氣服務保障，完善潛力預報和預案制定、條件監測和方案設計、信息收集與效果評估等全流程的6類人工影響天氣專項服務指導產品，并在河南、西藏林火等重大應急和重大活動服務保障中開展應用。

采用新技術、利用新資料，老中青同心聚力完成各項重大人工影響天氣專項保障服務。全年發布7種服務材料共245期，專題會商56次，2期決策服務材料報送黨中央，1期獲得中央領導同志的批示。積極參與國產大飛機試飛氣象保障工作。與商飛密切配合，利用進博會增雨作業飛行，開展自然結冰探測。與中航工業試飛院簽訂關于大飛機自然結冰項目戰略合作框架協議書。

6 研究型人工影響天氣業務發展

6 Reseach-oriented development of weather modification operations

6.1 指揮業務精細化發展

開展精細化云預報試驗。將人工影響天氣業務模式水平分辨率從3 km提高至1 km并開展試用，云水資源預報在重大服務中應用。改進人工影響天氣催化模式，利用WRF-AgI催化模式和對流云-AgI催化模式，實現飛機、火箭等人工增雨、消減雨和消雹催化的仿真模擬，進行了不同催化模式的催化效果比較研究。

提升國家級業務平臺功能和業務支撐能力。2021年7月1日，全國人工影響天氣綜合信息系統正式投入業務運行，該系統整合原有“人工影響天氣作業信息采集處理系統”和“人工影響天氣業務產品共享發布系統”，實現產品發布、信息上報、實時監控、業務管理和通知通報等功能?！叭斯び绊懱鞖饩C合信息系統”面向全國業務運行有效提升了人工影響天氣指導產品發布的時效性和作業信息采集的規范性。

開展國家級人工影響天氣核心業務系統融入“氣象大數據云平臺”工作。對各個業務系統賬戶進行了進一步的規范化管理，完善了系統的融入方案和實施進程。國家級人工影響天氣平臺已基本實現了從CIMISS平臺過渡到云平臺進行實時業務數據的采集。

6.2 人工影響天氣裝備安全運行

聯合有關省組建國家級飛機運行技術支持團隊，為國家飛機安全高效運行提供技術支持。對新疆、陜西國家飛機托管招標文件進行技術審查，把嚴把牢安全運行紅線。對國家飛機設備系統狀態及運行開展安全巡檢。

配合完成“3·1”事故處理。調研編制飛機安全運行及管理模式等的決策服務材料。推進相關標準規范建設，編制《人工影響天氣飛機安全檢查規范（試行）》《國家人工影響天氣飛機作業規程（試行）》和《國家人工影響天氣飛機航材庫管理辦法（試行）》等3項業務規范并經減災司印發全國執行。

完成人工影響天氣彈藥物聯網系統運行監控和作業裝備行政審批技術審核。配合減災司做好安全生產督查工作，編制安全檢查報告。

6.3 國內外交流合作

推進中泰、中韓、中阿、中沙在人工影響天氣領域的合作。（1）中泰合作：2021年2月9日，通過線上視頻會議的形式與泰國簽署了人工影響天氣技術合作協議。中泰雙方在2021年7月29日以線上的形式召開了技術交流討論會，進一步細化了雙方的合作計劃。（2）中韓交流：中國氣象局人工影響天氣中心與韓國國立氣象科學院于2021年12月30日舉辦了2021年中韓人工影響天氣技術視頻交流會。雙方主要討論了人工增雨效果檢驗相關問題（包括對比區的選取、增加雨量的計算、增雨作業的時效性等）、冰核觀測及設備相關情況，以及未來雙方可以開展的合作。（3）中阿交流：2021年4月12日，中國氣象局和阿聯酋國家氣象中心人工影響天氣專家14人舉行視頻會議，交流人工影響天氣技術研究和業務工作進展，研討未來合作意向。（4）中沙交流：應沙特阿拉伯方面要求對其關心的我國人工影響天氣領域的幾個方面內容進行答復。明確了中沙合作的聯系人。

組織籌辦12期云霧物理開放實驗室學術交流論壇，出版《全國人工影響天氣技術與方法交流會論文集（2020）》《氣象科技進展》西北人工影響天氣?？?021年11月）。

參加氣象科技活動周、全國林業和草原科技活動周、第18屆中國—東盟博覽會、國家“十三五”科技創新成就展，人工冰晶模擬系統獲得2021年氣象科技活動周優秀展項獎。人工影響天氣中心援疆專家在政府部門開展科普講座，使得人工影響天氣工作被更多人了解和認識，取得了良好的社會反響。

6.5 人工影響天氣標委會工作

積極推進項目申報和標準的編制進度。新頒布行業標準2項，國家標準1項；批復國標立項1項，國標外文版立項1項，行標7項，行標預研究1項；推薦申請國標1項；組織完成標準預審9次、正式審查10次，函審6次；組織開展標準網上征求意見工作5項。組織完成1項國標的網上立項投票。編輯印制了2003—2020年度人工影響天氣領域標準文集。