大氣物理與人工影響天氣
Atmospheric Physics and Weather Modif cation

云物理與人工影響天氣研究進(jìn)展

1 云物理觀測研究

1.1 華北一次持續(xù)性重度霧霾天氣的產(chǎn)生、演變與轉(zhuǎn)化特征觀測分析

2011年12月1—7日在華北地區(qū)發(fā)生了一次比較罕見、持續(xù)1周左右的低能見度重度霧霾天氣。利用氣象行業(yè)專項(xiàng)“京津地區(qū)低能見度霧霾天氣監(jiān)測與預(yù)報(bào)研究”觀測試驗(yàn)資料，研究分析了此次持續(xù)性重度霧霾天氣的氣溶膠、云凝結(jié)核（CCN）、霧滴譜、含水量等微物理特征及大氣能見度、邊界層垂直結(jié)構(gòu)特征，探討了霧霾天氣的產(chǎn)生、演變與轉(zhuǎn)化特征及機(jī)理。結(jié)果表明，此次持續(xù)1周的霧霾天氣過程發(fā)生在高壓天氣系統(tǒng)和靜風(fēng)條件下，暖平流和輻射降溫形成的穩(wěn)定逆溫邊界層結(jié)構(gòu)有利于污染氣溶膠的積累和霧霾的形成和發(fā)展，尤其是來自南方持續(xù)不斷的濕平流使霧霾天氣得以長時(shí)間持續(xù)和發(fā)展。整個(gè)霧霾天氣期間能見度均小于2 km，最低能見度達(dá)到56 m，液態(tài)水含量在10-3g/m3量級，最大達(dá)到0.16 g/m3，氣溶膠數(shù)濃度均在10000 cm-3以上，質(zhì)量濃度范圍為50～160 μg/m3。進(jìn)一步的研究表明，此次長達(dá)1周的霧霾天氣發(fā)生了3次強(qiáng)弱不同的霾氣溶膠積累、霾霧轉(zhuǎn)化和混合及減弱3個(gè)主要階段。霾氣溶膠積累階段先后有愛根核模和積聚模氣溶膠數(shù)濃度的積累和增加。霾向霧轉(zhuǎn)化和混合階段中，霧滴凝結(jié)釋放的潛熱和高濃度氣溶膠環(huán)境使布朗碰并加劇，導(dǎo)致氣溶膠尺度向粒徑大的方向轉(zhuǎn)移，從而提供了大量可形成云凝結(jié)核的氣溶膠粒子，促進(jìn)了霧的爆發(fā)性增強(qiáng)，濃霧過程中氣溶膠向CCN活化率可達(dá)17%，而CCN向霧滴的轉(zhuǎn)化效率可高達(dá)100%，此期間霧滴譜具有爆發(fā)性拓寬的特征；冷鋒系統(tǒng)過境或輻射加熱增強(qiáng)導(dǎo)致了霧霾過程的減弱和消散。（郭麗君，郭學(xué)良，方春剛，朱士超）

1.2 華北積層混合云中冰晶形態(tài)、分布與增長過程的飛機(jī)探測研究

利用國家科技支撐計(jì)劃重點(diǎn)項(xiàng)目“環(huán)北京地區(qū)3架飛機(jī)聯(lián)合云探測試驗(yàn)”數(shù)據(jù)，分析了2009年4月18日和5月1日2次積層混合云中冰晶形態(tài)、分布與增長過程。結(jié)果表明，飛機(jī)在0～16 ℃范圍的云層內(nèi)觀測的冰晶形態(tài)主要包括板狀、針柱狀、柱帽狀、輻枝狀和不規(guī)則狀。云中低層觀測的冰晶形態(tài)受云頂溫度影響，云頂溫度不同，觀測到的冰晶形態(tài)也不同，當(dāng)云頂溫度高于-8 ℃時(shí)，在云中低層觀測到的冰晶形態(tài)以板狀和針柱狀為主；當(dāng)云頂溫度低于-13 ℃時(shí)，在云中低層可觀測到輻枝狀冰晶；當(dāng)云頂溫度低于-18 ℃時(shí)，在云中低層可觀測到柱帽狀冰晶。同時(shí)冰晶形態(tài)還受其所處云中位置的影響，在積層混合云的嵌入對流區(qū)和融化帶中含有更多的凇附狀冰晶；在融化層以上，冰晶的增長過程主要包括凝華、凇附和聚合過程，在垂直方向上，隨著高度降低云中過冷水增多，冰晶的凇附增長也相應(yīng)增強(qiáng)。積層混合云中的對流區(qū)和層云區(qū)粒子譜下落拓寬速率有明顯差別，在4.8～4.2 km（-11.6～-8 ℃）高度層，對流區(qū)粒子譜拓寬速率為3 mm/km，而層云區(qū)為3.67 mm/km，層云中粒子拓寬增長的速率略高于對流區(qū)；而在4.2～3.6 km（-8～-5 ℃）高度層，對流區(qū)的粒子譜拓寬速率為6.67 mm/km，層云區(qū)為2.33 mm/km，對流區(qū)的粒子拓寬增長速率是層云區(qū)的近3倍，主要原因是嵌入對流層的低層含有較多過冷水。（朱士超，郭學(xué)良）

1.3 探測大氣溫濕廓線的35通道微波輻射計(jì)設(shè)計(jì)原理與特點(diǎn)

總結(jié)了自主研制的MWP967KV型地基35通道微波輻射計(jì)系統(tǒng)設(shè)計(jì)原理和主要特點(diǎn)。系統(tǒng)將K、V雙頻段寬帶天線及接收機(jī)、寬帶調(diào)頻本振、溫濕壓計(jì)以及電源模塊緊湊集成為一臺(tái)整體設(shè)備。對各傳感器的測量輸出實(shí)時(shí)進(jìn)行一體化綜合處理，采用BP神經(jīng)網(wǎng)絡(luò)實(shí)時(shí)反演大氣溫度、適度廓線和汽、水總量。廓線的垂直覆蓋范圍為地表至頂空10 km，共劃分為58層，輻射計(jì)樣機(jī)于2012年秋冬季在北京地區(qū)開展了為期2個(gè)月的觀測試驗(yàn)，利用這段時(shí)期內(nèi)的69個(gè)探空資料樣本對輻射計(jì)2個(gè)層次的實(shí)時(shí)觀測輸出都進(jìn)行了對比檢驗(yàn)，計(jì)算了水汽、氧氣通道亮溫和反演所得大氣溫濕廓線的平均偏差、均方差以及相關(guān)性。結(jié)果表明，該系統(tǒng)能夠滿足實(shí)時(shí)氣象監(jiān)測的需求，達(dá)到國際先進(jìn)水平。（盧建平，黃建平，郭學(xué)良）

1.4 L波段探空判別云區(qū)方法的研究

利用2008 年1月到2009年12月的L 波段探空資料，以及與之時(shí)空匹配的Cloudsat云觀測資料，分析云內(nèi)和云外相對濕度的累積頻率分布的結(jié)果顯示，以75%作為相對濕度閾值判斷云準(zhǔn)確率可達(dá)81%。利用BS（Bias Score）和TS（Threat Score）評分方法對不同相對濕度閾值進(jìn)行評分分析的結(jié)果顯示，以81%作為相對濕度閾值TS 評分可達(dá)0.66，為最高。利用BS和TS評分方法分不同高度對相對濕度閾值進(jìn)行評分分析，發(fā)現(xiàn)隨高度的增加該高度上具有最好TS評分的相對濕度閾值在減小。利用這些閾值對云判斷時(shí)，總的TS評分高于0.6，且準(zhǔn)確率達(dá)到84%以上，比利用單一相對濕度閾值判斷云準(zhǔn)確率要高。對這些閾值進(jìn)行優(yōu)化，得到一套適合于我國L波段探空秒數(shù)據(jù)的云垂直結(jié)構(gòu)的判別方法。（蔡淼，歐建軍，周毓荃）

1.5 一次超級單體雹暴觀測分析和成雹區(qū)識(shí)別研究

利用多普勒雷達(dá)資料，結(jié)合探空和常規(guī)資料，分析了2011年4月17 日一次超級單體雹暴的流場和回波結(jié)構(gòu)演變特征。該雹暴是在條件性不穩(wěn)定和垂直風(fēng)切變較大的環(huán)境下產(chǎn)生的右移風(fēng)暴。垂直剖面圖顯示雹云初生發(fā)展階段，逐漸形成有組織的斜上升氣流促進(jìn)雹云發(fā)展。成熟降雹階段，雹云內(nèi)形成一支強(qiáng)的斜上升氣流和深厚的中氣旋，主上升氣流對應(yīng)雹云的弱回波區(qū)。雹云維持典型的弱回波區(qū)-懸掛回波-回波墻特征結(jié)構(gòu)。根據(jù)雷達(dá)徑向速度和雹云移速訂正得出的“零線”演變發(fā)現(xiàn)，隨著雹云的發(fā)展，“零線”逐漸向懸掛回波靠近，并穿過懸掛回波，“零線”的走向?yàn)樯下N式，附近“穴道”的匯集力較強(qiáng)，有利于降雹。通過對“零線”位置的判斷可分析有利成雹的區(qū)域。根據(jù)高低空兩層強(qiáng)回波的水平錯(cuò)位，利用兩高度強(qiáng)中心連線所作剖面能快速準(zhǔn)確得出特征剖面，并將0℃層以上6 km 高度處降雹潛勢達(dá)到100%的45 dBz的區(qū)域識(shí)別為成雹區(qū)，與降雹實(shí)況對比發(fā)現(xiàn)識(shí)別效果良好。（蔡淼，周毓荃）

1.6 一次西風(fēng)槽過程過冷云水分布特征觀測研究

過冷云水生消演變規(guī)律是云物理學(xué)和人工影響天氣的重要研究領(lǐng)域。根據(jù)Hobbs 1974年提出的假定，利用飛機(jī)、衛(wèi)星、雷達(dá)和雨量計(jì)等觀測資料，對2012年9月21日河北一次西風(fēng)槽天氣過程進(jìn)行觀測研究，分析其過冷云水分布特征及演變規(guī)律。結(jié)果表明，槽前云系過冷水區(qū)寬厚并且過冷水含量較高，云滴濃度和均立方根直徑較大并且均勻，冷云區(qū)厚而且沒有分層，沒有暖云配合；近槽云系中冷云區(qū)小粒子濃度降低但云滴直徑增大，冷云區(qū)夾有干層，云系變厚出現(xiàn)暖云配合，冷暖云液態(tài)水含量較高，冷暖云區(qū)大粒子和降水粒子濃度和尺度增大，中尺度云團(tuán)移動(dòng)較快；槽后云系中云滴濃度最大，但云滴均立方根直徑明顯減小，過冷水區(qū)出現(xiàn)的高度下降、厚度很薄、過冷水含量較低，冷、暖云之間有干層，暖云對應(yīng)的大粒子濃度和降水粒子濃度非常大，地面降水主要由暖云過程產(chǎn)生；云水（過冷水）含量峰值常出現(xiàn)在云內(nèi)逆溫層的上方；利用云粒子測量系統(tǒng)（PMS）資料分析過冷云水生消演變特征，其與衛(wèi)星和雷達(dá)資料具有較高的一致性。（周毓荃，孫晶）

2 云降水物理與人工影響天氣數(shù)值模擬研究

2.1 氣溶膠對華北夏季對流云和降水影響的數(shù)值模擬研究

大氣溫室氣體、氣態(tài)前體物和顆粒物排放可以直接改變大氣輻射收支，或間接改變云和降水過程，可能引起區(qū)域到全球尺度的氣候和水循環(huán)變化。一些前期發(fā)表的大氣排放對云和降水影響的定量評估研究結(jié)果并不一致。本研究利用MODIS衛(wèi)星和WRF-CHEM模式，對2008年7月4日華北城市區(qū)一次對流性降水個(gè)例的氣溶膠特性及其對降水的可能影響進(jìn)行了分析。結(jié)果表明，研究區(qū)氣溶膠光學(xué)厚度超過0.9，說明存在高濃度污染氣溶膠。愛根指數(shù)大于1.0，說明研究區(qū)主要?dú)馊苣z粒子屬于工業(yè)和生物質(zhì)燃燒所產(chǎn)生，粒徑尺度在0.25～0.5 μm。數(shù)值模擬研究表明，污染條件下模擬區(qū)域平均降水增加17%，但大于30 mm/h的降水強(qiáng)度出現(xiàn)增強(qiáng)，而小于30 mm/h的降水強(qiáng)度減弱。污染與清潔狀況下的云微物理和動(dòng)力差異表明，污染對風(fēng)暴初始和消散階段的冷暖云微物理、動(dòng)力過程和上升氣流有明顯抑制作用，而對成熟期的風(fēng)暴有明顯增強(qiáng)作用。（郭學(xué)良）

2.2 減弱對流云降水的AgI催化原理的數(shù)值模擬研究

在對流云模式中增加了AgI兩個(gè)預(yù)報(bào)量，耦合了考慮受水汽過飽度和溫度影響的4種核化機(jī)制的AgI催化模塊，使其具備了AgI 類催化劑的模擬能力，能夠研究AgI 類催化劑對對流云系統(tǒng)的影響。利用此模式對一次華南對流云降水過程進(jìn)行了AgI成冰劑催化數(shù)值模擬試驗(yàn)，對人工減緩對流云降水的可能性及原理進(jìn)行了研究。模擬結(jié)果表明，在適當(dāng)?shù)臅r(shí)機(jī)對適當(dāng)?shù)牟课贿M(jìn)行大劑量的催化，可以減少總降水量，也可以減弱最大降水中心的雨強(qiáng)。當(dāng)催化劑量達(dá)到2×108kg-1時(shí)，可以減少32%的降水量，具備有效減緩對流云降水成災(zāi)的可能性。大劑量催化后，大量的AgI粒子在冷區(qū)核化后消耗了大量的過冷水。催化后霰粒子的落速和雨水的落速減小。催化階段由于霰融化成雨水減少而使降水減弱。催化結(jié)束后在霰融化成雨水增多的情況下，雨水的蒸發(fā)大幅增加，從而導(dǎo)致了降水量的持續(xù)減少。AgI在此次強(qiáng)對流云中主要以受過飽和度影響的凝結(jié)凍結(jié)和催化劑長時(shí)間作用的浸沒凍結(jié)這兩種方式成核。研究所用催化方法在外場作業(yè)中具有技術(shù)可行性。（樓小鳳，孫晶，史月琴，張邢）

2.3 下墊面對雹云形成發(fā)展的影響

利用中尺度模式WRF對2005 年5 月31 日發(fā)生在北京地區(qū)的一次強(qiáng)冰雹天氣過程進(jìn)行了數(shù)值模擬研究，并與觀測的雷達(dá)回波、冰雹云移動(dòng)路徑和冰雹落區(qū)進(jìn)行比較，在此基礎(chǔ)上探討了城市和農(nóng)田兩種下墊面對雹云的影響。結(jié)果表明，由于“城市熱島”效應(yīng)的作用，城市下墊面的地面感熱通量顯著增加，有利于雹云的發(fā)展增強(qiáng)和大冰雹的形成，使地面累積降雹量增加，但對雹云移動(dòng)路徑影響不大。農(nóng)田下墊面具有較大的潛熱通量，局地蒸發(fā)強(qiáng)，有利于大量小冰雹的形成，云中冰雹含量增加，但降雹強(qiáng)度較弱，地面累積降雹量小。（郭學(xué)良）

2.4 一次積層混合云降水不同尺度結(jié)構(gòu)的數(shù)值模擬

利用中尺度數(shù)值模式WRF-ARW（V3.2）對2009年4月18—19日發(fā)生在張家口地區(qū)的一次積層混合云降水進(jìn)行了模擬，并結(jié)合觀測資料從不同尺度對這次降水過程進(jìn)行了對比分析。結(jié)果表明，700 hPa西風(fēng)槽、850 hPa低渦是影響這次降水的主要天氣系統(tǒng)，來自南方的暖濕空氣和西北內(nèi)蒙古低渦帶來的水汽是這次降水的主要水汽來源，兩股水汽在張家口附近低層出現(xiàn)了大尺度輻合，有利于該地區(qū)云系的發(fā)展和降水的形成。降水云系呈東北—西南向帶狀分布，帶長約1000 km，帶寬300 km，在大片的云帶中分布著很多個(gè)小的高值中心，中心區(qū)域一般在幾十公里；結(jié)合雷達(dá)回波可以看到在均勻的回波層中鑲嵌著柱狀對流回波，具有典型的積層混合云降水回波特征；沿著雷達(dá)回波做剖面，發(fā)現(xiàn)云中云水含量分布無論是在水平方向還是垂直方向都是不均勻的，雨水的大值中心與上層的霰、雪的大值中心相對應(yīng)，中心水平范圍在10～20 km。（張微，周毓荃）

2.5 山西春季層狀云系數(shù)值模擬及與飛機(jī)探測對比

采用中國氣象科學(xué)研究院中尺度云參數(shù)化模式對2010年4月20日山西省一次春季層狀降水云系的宏微觀結(jié)構(gòu)，特別是垂直方向上的微物理結(jié)構(gòu)進(jìn)行了數(shù)值模擬和分析。利用攜帶云粒子探測設(shè)備的飛機(jī)對該次層狀云系進(jìn)行了2次云物理探測飛行，并將飛機(jī)探測所獲取的數(shù)據(jù)和圖像資料與數(shù)值模擬結(jié)果進(jìn)行了對比研究。模擬結(jié)果顯示，該次降水過程以層狀冷云降水為主，云中過冷水含量豐富，云系存在明顯的3層結(jié)構(gòu)，地面降水主要來自于云中高層冰晶、雪、霰等冰相粒子的融化和低層云水的轉(zhuǎn)化。數(shù)值模擬與飛機(jī)探測對比分析顯示，高空溫度、濕度和高度的配置兩者基本一致，數(shù)值模擬不同高度的云粒子相態(tài)、垂直方向云水比含水量與飛機(jī)探測獲取的云粒子圖像和云液態(tài)水含量的垂直結(jié)構(gòu)基本吻合，但數(shù)值模擬的云中各種水成物粒子出現(xiàn)的高度較飛機(jī)探測偏高。（陶玥，史月琴）

3 人工影響天氣關(guān)鍵技術(shù)研究

3.1 高炮、火箭和飛機(jī)催化擴(kuò)散規(guī)律和作業(yè)設(shè)計(jì)

基于擴(kuò)散計(jì)算的解析解提出了針對高炮、火箭和飛機(jī)等不同催化方式的點(diǎn)源、多線源和移動(dòng)點(diǎn)源的數(shù)值計(jì)算方案，分別研究了不同催化方式催化劑擴(kuò)散規(guī)律和有效范圍，并利用衛(wèi)星捕獲的一次飛機(jī)播云實(shí)例檢驗(yàn)了計(jì)算方案，同時(shí)研究了實(shí)現(xiàn)目標(biāo)區(qū)充分催化的作業(yè)設(shè)計(jì)等問題。高炮作為點(diǎn)源催化、單個(gè)高炮作業(yè)，達(dá)到有效催化濃度的范圍半徑只有約0.5 km，應(yīng)當(dāng)采用多炮彈密集作業(yè)，比較有利于濃度和催化范圍的維持，提高炮彈成核率能夠明顯提高高炮作業(yè)效果。火箭和飛機(jī)作為線源催化，1 h內(nèi)達(dá)到有效催化濃度的寬度分別為7 km和6.6 km，此寬度可作為多線播撒作業(yè)飛行間距設(shè)計(jì)的參考依據(jù)；飛機(jī)單線播撒達(dá)不到充分催化的要求，而耕作式播撒，在風(fēng)速作用下擴(kuò)散區(qū)域會(huì)分散或重疊。根據(jù)風(fēng)速大小設(shè)計(jì)的“8”字形來回播撒飛行路線，可使目標(biāo)區(qū)得到充分播撒。在擴(kuò)散計(jì)算方案研究基礎(chǔ)上研發(fā)的各類催化擴(kuò)散計(jì)算和作業(yè)設(shè)計(jì)軟件系統(tǒng)，可方便準(zhǔn)確地計(jì)算飛機(jī)、高炮和火箭實(shí)際作業(yè)時(shí)催化劑在云中擴(kuò)散的范圍、濃度及其隨時(shí)間的演變，并可針對不同目標(biāo)區(qū)進(jìn)行充分播撒催化的作業(yè)設(shè)計(jì)，結(jié)果直觀簡明，為催化擴(kuò)散計(jì)算的實(shí)際業(yè)務(wù)應(yīng)用和作業(yè)設(shè)計(jì)提供了幫助。（周毓荃）

3.2 北京地區(qū)人工增雨效果和防雹經(jīng)濟(jì)效益評估

基于全市農(nóng)業(yè)氣象災(zāi)情統(tǒng)計(jì)資料，結(jié)合近年來北京地區(qū)開展的人工增雨、防雹作業(yè)情況，利用經(jīng)典的區(qū)域歷史回歸統(tǒng)計(jì)方法，對2004—2010年人工增雨效果和防雹經(jīng)濟(jì)效益進(jìn)行了客觀定量評估。結(jié)果表明：（1）在5—9月的評估期，隨著作業(yè)樣本數(shù)逐年累加，人工增雨平均相對增雨率逐漸趨于穩(wěn)定，并維持在20%左右，在所選目標(biāo)區(qū)連續(xù)7年的人工增雨作業(yè)累計(jì)增加降水量約417.8 mm，增雨效果非常顯著；（2）年平均人工防雹經(jīng)濟(jì)效益約2.48億元，多年平均防雹投入產(chǎn)出比為1：16。人工防雹效益最高、最低年份分別為2009年和2005年，對應(yīng)投入產(chǎn)出比分別為1：27和1：6。（李宏宇）

3.3 對流云人工增雨效果檢驗(yàn)技術(shù)方法及應(yīng)用

對流云降水時(shí)空變化較大，利用Woodley & Rosenfeld提出的建立在雷達(dá)資料基礎(chǔ)上的移動(dòng)目標(biāo)單元法對對流云增雨作業(yè)進(jìn)行效果評估。利用塘沽、北京及秦皇島3部雷達(dá)資料，對其進(jìn)行插值處理，確定移動(dòng)目標(biāo)單元識(shí)別和跟蹤方法，然后在移動(dòng)目標(biāo)單元中確定催化單元和對比單元，記錄每個(gè)單元的物理參量，利用Z-R關(guān)系反演降水量，對物理參量和反演降水量作統(tǒng)計(jì)分析，定量計(jì)算增雨效果的同時(shí)提供人工增雨的物理證據(jù)。應(yīng)用該方法對2011年7月24日對流云人工增雨作業(yè)效果進(jìn)行評估的結(jié)果表明，催化劑進(jìn)入云中后使得最大回波強(qiáng)度增強(qiáng)、回波頂高增加，從物理角度證明了催化對增加降水起到了一定作用。利用降雨率對增雨作業(yè)定量效果分析的結(jié)果表明，該次作業(yè)相對增雨7.69%，顯著度檢驗(yàn)值為0.043。（李宏宇）

4 人工影響天氣工程建設(shè)及業(yè)務(wù)工作進(jìn)展

4.1 全國人工影響天氣發(fā)展規(guī)劃（2014—2020年）

為了避免這種情況的出現(xiàn)，在類比時(shí)要選擇與目標(biāo)相關(guān)的屬性或關(guān)系。類比推理是有目的性的推理，目的性是類比推理的一個(gè)重要的約束。另外，概念聚類可以根據(jù)線索概念在概念網(wǎng)絡(luò)中生成，圍繞不同的線索概念可以形成不同的概念聚類，這也限制了類比的不合理擴(kuò)展。在老子關(guān)于水的類比中，目標(biāo)是用來說明善的，在概念網(wǎng)絡(luò)中形成概念聚類，也是以具有水的正面意義的概念為線索的。這樣就將水的負(fù)面特質(zhì)或與善不相關(guān)的概念排除在概念網(wǎng)絡(luò)之外了。

2014年12月，中國氣象局人工影響天氣中心牽頭編制的《全國人工影響天氣發(fā)展規(guī)劃（2014—2020年）》（發(fā)改農(nóng)經(jīng)〔2014〕2864號(hào)）由國家發(fā)展改革委員會(huì)和中國氣象局聯(lián)合印發(fā)，該規(guī)劃確定了全國人工影響天氣的指導(dǎo)思想、發(fā)展目標(biāo)、總體布局、主要任務(wù)、實(shí)施安排，提出了人工影響天氣的組織管理體制和業(yè)務(wù)運(yùn)行機(jī)制，是當(dāng)前及今后一段時(shí)期全國人工影響天氣發(fā)展的行動(dòng)綱領(lǐng)，對全國人工影響天氣現(xiàn)代化建設(shè)和科學(xué)發(fā)展具有重要指導(dǎo)意義。2014年10—11月，《全國人工影響天氣業(yè)務(wù)發(fā)展指導(dǎo)意見》（氣發(fā)〔2014〕95號(hào)文）、《人工影響天氣專用技術(shù)裝備管理辦法》（氣發(fā)〔2014〕106號(hào)文），相繼由中國氣象局正式印發(fā)頒布，標(biāo)志著我國人工影響天氣業(yè)務(wù)和裝備管理步入規(guī)范發(fā)展的軌道。（陳添宇，周毓荃，房文）

4.2 東北人工影響天氣工程建設(shè)

2014年是“東北區(qū)域人工影響天氣能力建設(shè)”項(xiàng)目建設(shè)初見效益的重要一年。年度內(nèi)，完成初步設(shè)計(jì)的修訂與報(bào)批，首架新舟60 增雨機(jī)試飛成功并在第10屆中國國際航空航天博覽會(huì)上正式亮相，完成第3架高性能增雨飛機(jī)作業(yè)系統(tǒng)總體方案設(shè)計(jì)并選定了11套機(jī)載人工影響天氣設(shè)備，啟動(dòng)區(qū)域飛機(jī)作業(yè)保障中心建設(shè)，作業(yè)指揮應(yīng)用系統(tǒng)主體功能已在東北4省區(qū)安裝部署；完成高性能作業(yè)飛機(jī)衛(wèi)星通信系統(tǒng)、79部全球定位系統(tǒng)氣象觀測（GPS/MET）設(shè)備、3部X波段移動(dòng)多普勒天氣雷達(dá)、GPS/ MET數(shù)據(jù)處理中心軟件系統(tǒng)以及效果檢驗(yàn)外場試驗(yàn)區(qū)所有設(shè)備的采購，舉辦了人工影響天氣前沿科學(xué)技術(shù)與飛機(jī)作業(yè)技術(shù)培訓(xùn)班。項(xiàng)目初步成果在東北區(qū)域春夏季抗旱增雨中發(fā)揮了重要作用。（李集明，陳衛(wèi)紅）

4.3 全國人工影響天氣作業(yè)信息采集處理系統(tǒng)（V1.0版）投入業(yè)務(wù)運(yùn)行

在多年業(yè)務(wù)工作的基礎(chǔ)上，依托“中國氣象局人工影響天氣業(yè)務(wù)指揮平臺(tái)”項(xiàng)目建設(shè)的全國人工影響天氣作業(yè)信息采集處理系統(tǒng)（V1.0版）于5月21日通過專家組驗(yàn)收，成為2014年繼人工影響天氣預(yù)報(bào)模式系統(tǒng)后，第2個(gè)通過業(yè)務(wù)化驗(yàn)收的人工影響天氣業(yè)務(wù)系統(tǒng)（氣減函〔2014〕48號(hào)文）。

全國人工影響天氣作業(yè)信息采集處理系統(tǒng)（V1.0版）由作業(yè)信息采集處理系統(tǒng)和實(shí)時(shí)上報(bào)系統(tǒng)2部分構(gòu)成，依托全國氣象業(yè)務(wù)寬帶網(wǎng)，可實(shí)現(xiàn)全國人工影響天氣作業(yè)信息的上報(bào)、采集、存儲(chǔ)、監(jiān)控、管理等功能；同時(shí)集成了站點(diǎn)信息、作業(yè)信息、人員信息、彈藥信息等多種人工影響天氣基礎(chǔ)數(shù)據(jù)，為人工影響天氣作業(yè)效果分析評估、聯(lián)合作業(yè)指導(dǎo)、人工影響天氣決策服務(wù)產(chǎn)品制作提供及時(shí)、可靠的信息來源。系統(tǒng)投入業(yè)務(wù)運(yùn)行以來，有效地提高了地方人工影響天氣部門作業(yè)信息上報(bào)效率，加強(qiáng)了國家級人工影響天氣中心的業(yè)務(wù)指導(dǎo)能力和服務(wù)效益，為各地人工影響天氣作業(yè)指揮和效果分析等業(yè)務(wù)的開展提供了有力支撐。（王飛，楊連英，李抗抗）

4.4 人工影響天氣云降水特征參量靜止衛(wèi)星反演系統(tǒng)（CPPS-GSSL 2.0版）投入業(yè)務(wù)運(yùn)行

該反演系統(tǒng)（CPPS-GSSL 2.0版），是基于我國FY-2系列靜止氣象衛(wèi)星和L波段探空資料等實(shí)時(shí)反演生成云黑體亮溫、云頂高度、云頂溫度、過冷層厚度、云光學(xué)厚度、云粒子有效半徑和液水路徑等云特征參量反演產(chǎn)品，通過與MODIS反演參量的對比檢驗(yàn)及與CloudSat云雷達(dá)、天氣雷達(dá)、雨滴譜和地面降水等多種云降水觀測進(jìn)行物理合理性分析，檢驗(yàn)了反演產(chǎn)品的準(zhǔn)確性和可用性。反演產(chǎn)品在各省應(yīng)用效果好，已為重點(diǎn)干旱地區(qū)及跨區(qū)域增雨作業(yè)、森林草原滅火增雨作業(yè)、重大社會(huì)活動(dòng)消減雨作業(yè)等提供了強(qiáng)有力的技術(shù)支撐。（蔡淼，周毓荃）

4.5 2014年南京青奧會(huì)開、閉幕式人工消減雨取得明顯效果

2014年8月16日和28日，第2屆夏季青年奧林匹克運(yùn)動(dòng)會(huì)開、閉幕式分別于南京市奧體中心舉行。為確保其順利進(jìn)行，組委會(huì)迫切要求開展人工消減雨試驗(yàn)和服務(wù)。江蘇省氣象局特邀中國氣象局人工影響天氣中心全程指導(dǎo)開展相關(guān)試驗(yàn)和服務(wù)工作，并取得明顯消減雨效果。其中開幕式奧體中心場館降水2 mm，場館周邊鄰近站平均降水5 mm；閉幕式奧體中心場館降水0.2 mm，場館周邊鄰近站平均降水0.68 mm。確保了開、閉幕式的順利進(jìn)行。初步總結(jié)關(guān)鍵技術(shù)工作主要如下。

（1）在分析研究8月份南京天氣和云降水特征基礎(chǔ)上，提出并指導(dǎo)制定了南京青奧會(huì)人工影響天氣服務(wù)技術(shù)方案，包括監(jiān)測加密、通信指揮、作業(yè)防線布局和實(shí)施組織等多個(gè)分方案。

（2） 利用國家近年發(fā)展的人工影響天氣作業(yè)條件業(yè)務(wù)數(shù)值預(yù)報(bào)模式，提前24 h給出催化原理、催化方案（包括催化區(qū)、催化時(shí)段、催化方式及催化量的預(yù)報(bào)）。并結(jié)合天氣動(dòng)力預(yù)報(bào)和實(shí)況監(jiān)測，利用新建的人工影響天氣遠(yuǎn)程會(huì)商平臺(tái)，進(jìn)行國家人工影響天氣指揮中心同青奧會(huì)現(xiàn)場指揮中心的實(shí)時(shí)互動(dòng)，滾動(dòng)進(jìn)行作業(yè)方案的實(shí)時(shí)會(huì)商和預(yù)報(bào)方案的及時(shí)修訂，并達(dá)到預(yù)期催化效果。

（3）將中國氣象局人工影響天氣中心近年來研究發(fā)展的云降水精細(xì)分析系統(tǒng)（CPAS）移植開發(fā)，建立了青奧會(huì)消減雨作業(yè)指揮系統(tǒng)，實(shí)現(xiàn)基于衛(wèi)星、雷達(dá)、探空及特種儀器等各類觀測的云系宏微觀結(jié)構(gòu)和降水演變的實(shí)時(shí)精細(xì)分析、作業(yè)條件的預(yù)判識(shí)別、最佳的作業(yè)方案的實(shí)時(shí)設(shè)計(jì)滾動(dòng)修正、現(xiàn)場飛機(jī)和地面多種催化的實(shí)時(shí)指揮等功能。

（4）利用移植的CPAS平臺(tái)和作業(yè)指揮系統(tǒng)，有效組織飛機(jī)外圍偵查探測預(yù)作業(yè)和臨近區(qū)域高密度火箭催化作業(yè)，有效地抑制削弱了移近場館的云團(tuán)，證實(shí)了作業(yè)前的技術(shù)原理和設(shè)計(jì)，取得了較好的預(yù)期效果（圖1 ）。（周毓荃，劉思瑤，濮梅娟，胡志晉）

4.6 國家級人工影響天氣業(yè)務(wù)平臺(tái)的建設(shè)及其在業(yè)務(wù)指導(dǎo)和服務(wù)中的作用

2014年人工影響天氣中心自主研發(fā)建設(shè)完成國家級人工影響天氣業(yè)務(wù)平臺(tái)，該平臺(tái)主要包括4部分功能。第1部分是信息傳輸、收集與存儲(chǔ)管理功能，主要收集存儲(chǔ)常規(guī)氣象觀測數(shù)據(jù)、人工影響天氣特種觀測、業(yè)務(wù)產(chǎn)品和飛機(jī)、地面人工影響天氣作業(yè)數(shù)據(jù)，供實(shí)時(shí)業(yè)務(wù)使用，并處理形成典型個(gè)例庫數(shù)據(jù)；第2部分是產(chǎn)品加工、檢驗(yàn)和中試功能，主要對數(shù)據(jù)進(jìn)行加工處理，綜合分析形成各種人工影響天氣特征量，用于對人工影響天氣作業(yè)條件進(jìn)行預(yù)報(bào)和監(jiān)測預(yù)警，并對預(yù)報(bào)產(chǎn)品進(jìn)行檢驗(yàn)和新業(yè)務(wù)開發(fā)中試；第3部分是業(yè)務(wù)指導(dǎo)和服務(wù)功能，包括開展作業(yè)條件潛力預(yù)報(bào)、監(jiān)測預(yù)警與專題會(huì)商、設(shè)計(jì)作業(yè)方案、開展飛機(jī)作業(yè)跟蹤指揮和實(shí)時(shí)監(jiān)控，以及作業(yè)后效果檢驗(yàn)分析；第4部分是產(chǎn)品共享發(fā)布功能，將預(yù)報(bào)和監(jiān)測產(chǎn)品通過網(wǎng)站進(jìn)行發(fā)布，供相關(guān)業(yè)務(wù)單位使用。

平臺(tái)建成后，針對我國各地出現(xiàn)的旱情和可能的作業(yè)天氣過程，成功進(jìn)行跨?。▍^(qū)）聯(lián)合業(yè)務(wù)會(huì)商，在實(shí)時(shí)業(yè)務(wù)指導(dǎo)和服務(wù)中發(fā)揮重要作用。如在2014年4月，中國氣象局人工影響天氣中心聯(lián)合黑龍江、吉林、遼寧、內(nèi)蒙古4?。▍^(qū)）人工影響天氣中心進(jìn)行會(huì)商，對整個(gè)東北區(qū)域的云系結(jié)構(gòu)、云帶、過冷水、冰相粒子等的分布和演變情況進(jìn)行綜合分析，提出了適合開展作業(yè)的時(shí)間、地點(diǎn)和高度等方面的建議；東北人工影響天氣中心根據(jù)東北區(qū)域作業(yè)需求和作業(yè)裝備的布局進(jìn)行了跨?。▍^(qū)）聯(lián)合作業(yè)的部署，標(biāo)志著跨省（區(qū)）聯(lián)合作業(yè)步入逐級指導(dǎo)、聯(lián)合作業(yè)的業(yè)務(wù)模式，提高作業(yè)的科技水平和效益（圖2）。（周毓荃，史月琴，孫晶，蔡淼，劉衛(wèi)國，陶玥，王飛）

4.7 優(yōu)化空中云水資源評估

通過2011—2014年的不斷探索和研究，中國氣象局人工影響天氣中心研發(fā)完善了空中云水資源監(jiān)測評估方法（CWR-MEM）。該方法以大氣水分收支平衡方程為基礎(chǔ)，明確了包括水凝物在內(nèi)的大氣水物質(zhì)概念，完善了各種水物質(zhì)總量、降水效率、更新周期等概念和計(jì)算公式，提出了云水資源、空中云水資源總量和有效云水資源量等相關(guān)概念。

2014年，中國氣象局人工影響天氣中心組織專門技術(shù)力量，對該方案中三維云場和三維云水場的診斷識(shí)別等關(guān)鍵技術(shù)和評估時(shí)空尺度、復(fù)雜區(qū)域邊界處理等評估方法進(jìn)行了優(yōu)化。根據(jù)云的氣候特性，將中國按經(jīng)緯度分為5個(gè)區(qū)域，利用2007—2008年的CloudSat云觀測產(chǎn)品，分別統(tǒng)計(jì)得出各區(qū)域診斷云區(qū)的相對濕度閾值和云含水量典型值及其垂直分布，并將垂直分布隨高度坐標(biāo)改為溫度坐標(biāo)，云場物理意義更準(zhǔn)確，明顯改進(jìn)優(yōu)化了全國不同區(qū)域三維云場和三維云水場的診斷方案。對空中云水資源評估時(shí)，將評估區(qū)域細(xì)分為6個(gè)區(qū)域，并將各區(qū)域的邊界處理成1°分辨率的閉合曲線，明顯改進(jìn)了對凝結(jié)和蒸發(fā)量的計(jì)算，提高了整體評估精度和計(jì)算準(zhǔn)確率。

利用優(yōu)化的CWR-MEM方案，對2008—2010年中國六大人工影響天氣區(qū)域的空中云水資源進(jìn)行了評估，完成了2014年空中云水資源監(jiān)測評估報(bào)告。主要評估結(jié)果如下：2008—2010年，中國的水汽總量年平均值（GQv）約36.9×1012t，其中從各邊界輸入的水汽量年平均值約33.1×1012t，蒸發(fā)量年平均值約3.75×1012t；水凝物總量（GQh）年平均值約7.15×1012t，降水總量（GR）年平均值約5.02×1012t，云水資源總量年平均值（GCWR）約2.13×1012t，有效云水資源量年平均值（CWR）約1.23×1012t。水汽降水效率年平均值約為14%，水凝物降水效率年平均值約為70%，水汽更新周期年平均值約為10天，水凝物更新周期年平均值約為7 h。云水資源各特征量具有明顯的時(shí)空分布差異。（周毓荃，蔡淼）

4.8 研發(fā)作業(yè)效果檢驗(yàn)技術(shù)方法

在詳細(xì)分析全國人工影響天氣作業(yè)信息的基礎(chǔ)上，揭示了全國不同區(qū)域的人工增雨作業(yè)需求；開發(fā)了4種非隨機(jī)化人工增雨效果統(tǒng)計(jì)檢驗(yàn)技術(shù)方法，研發(fā)了針對4種統(tǒng)計(jì)檢驗(yàn)方案的顯著性水平檢驗(yàn)算法，并在江西、云南、河南、重慶、安徽5個(gè)試點(diǎn)省進(jìn)行試驗(yàn)試用；研發(fā)了基于TITAN技術(shù)的播云多普勒雷達(dá)識(shí)別追蹤及檢驗(yàn)算法和基于常規(guī)雷達(dá)探測資料的人工增雨效果物理檢驗(yàn)技術(shù)方法，并在試點(diǎn)省進(jìn)行試驗(yàn)試用；對試點(diǎn)省2013年人工增雨作業(yè)典型個(gè)例進(jìn)行了效果檢驗(yàn)，給出了試點(diǎn)省人工增雨作業(yè)效果及其統(tǒng)計(jì)顯著性水平；在試點(diǎn)省開展了基于歷史降水資料的區(qū)域相關(guān)分析研究，為科學(xué)開展人工增雨作業(yè)和效果檢驗(yàn)工作進(jìn)行理論積累；通過分析影響試點(diǎn)省的主要天氣系統(tǒng)和歷史作業(yè)情況，結(jié)合試點(diǎn)省歷史降水區(qū)域相關(guān)分析研究結(jié)果，給出試點(diǎn)省人工增雨主要作業(yè)影響區(qū)和對比區(qū)的區(qū)劃設(shè)想；完成了2014年度全國人工增雨效果檢驗(yàn)工作總結(jié)報(bào)告。（姚展予）

4.9 高效冷暖云催化劑的研制及新裝備測試、考核和業(yè)務(wù)試用

中國氣象局人工影響天氣中心組織開展了WMC-IN-001、WMC-IN-002型2種冷云催化劑和WMCCN-001型吸濕性催化劑配方的調(diào)整、改進(jìn)試驗(yàn)研究，并對催化劑的成核率進(jìn)行檢測。與目前業(yè)務(wù)用的焰劑類冷云催化劑成核率相比，新型冷云催化劑成核率高一個(gè)量級以上。播撒WMC-CN-001型吸濕性催化劑后，在多個(gè)速度下，大于2 μm的粒子濃度均可達(dá)到 101量級；冷暖云催化劑研究成果均通過了技術(shù)認(rèn)定。研制的暖云催化劑已在福建、安徽開展地面燃燒爐的業(yè)務(wù)試用，在河北開展飛機(jī)播撒試用；對業(yè)務(wù)用機(jī)載煙條、煙彈和地面煙條等催化劑的成核率進(jìn)行了統(tǒng)一檢測，保障了催化劑的作業(yè)效率；組織了隨州大方精密機(jī)電工程有限公司生產(chǎn)的“DF37 mm高射炮遠(yuǎn)程控制系統(tǒng)”和華云公司生產(chǎn)的“HY-1型機(jī)載焰條播撒系統(tǒng)”的產(chǎn)品定型和業(yè)務(wù)試用方案的評審。（房文，黨娟，方春剛，蘇正軍，汪曉濱，劉汐敬）

圖1 2014年8月28日閉幕式主要影響云帶回波平均值及強(qiáng)回波（大于20 dBz）面積隨時(shí)間的演變（多輪次作業(yè)后保障區(qū)，保障時(shí)段（20:15—22:08）回波減弱最明顯）Fig. 1 August 28, 2014, the average echo of the statistical areas and the echo areas stronger than 20 dBz of the main inf uenceing cloud band during the closing ceremony (The most weakened echo effect time is 20:15–22:08 after the large operations)

圖2 國家級人工影響天氣業(yè)務(wù)平臺(tái)總體結(jié)構(gòu)Fig. 2 Structure of national weather modif cation operational platform

Advances in Cloud Physics and Weather Modif cation

1 Observational studies on cloud physics

1.1 Observation and analysis of characteristics of formation, evolution and transition of a longlasting severe fog and haze episode in North China

An unusual fog and haze event lasting for one week occurred during 1–7 December 2011 over North China. To investigate the characteristics and mechanism of formation, evolution and transition of the fog and haze event, the microphysical properties such as aerosol, cloud condensation nuclei (CCN), fog droplet spectrum and liquid water content (LWC), as well as horizontal visibility and boundary layer properties were studied by using the data collected in the project of Low-Visibility Weather Monitoring and Forecasting in the Beijing-Tianjin region. The results indicate that the long-lasting fog and haze event occurred in a high pressure weather system and calm wind condition. The stable boundary-layer structure resulting from temperature inversions caused by warm advection and radiation cooling provided a favorable condition for the accumulation of polluted aerosols, and the formation and development of the fog and haze event. In particular, the continuous southerly wet advection led to a long process. The horizontal visibility was almost below 2 km in the whole process, with the lowest being only 56 m. The average LWC was about 10-3g m-3, with the maximum reaching 0.16 g m-3. The aerosol number concentration was more than 10000 cm-3, with the mass concentration ranging from 50 to 160 μg m-3. The further study shows that the fog and haze event experienced three main different processes in intensity during the whole period, each process being divided into three main stages: aerosol accumulation, transition and mixture of aerosol and fog, and dissipation. Each stage had different physical features: the aerosol accumulation stage was characterized by the increase of aerosol number concentration in Aitken nuclei and accumulation mode sequentially. In the transition and mixing stage of fog and haze, the latent heating produced by the fog droplet condensation process and high aerosol number concentration condition intensif ed the Brownian coagulation process, which induced the small size of aerosols to become larger ones and enhanced the CCN activation process, thereby promoting the explosive development of the fog event. The ratio of aerosol activated to CCN reached 17%, and the ratio of CCN converted to fog droplets exceeded 100%, showing an explosive broadening of fog droplet spectrum. The decrease and dissipation of the fog were caused by an increased solar radiation heating or the passage of cold frontal system. (Guo Lijun, Guo Xueliang, Fang Chungang, Zhu Shichao)

1.2 Ice crystal habits, distribution and growth processes in stratiform clouds with embedded convection in North China: Aircraft measurements

Ice crystal habits, distribution and growth processes in two cases of stratiform clouds with embedded convection on 18 April and 1st May 2009 are analyzed with data observed during the Beijing Cloud Experiment (BCE). The results show that ice crystal habits in clouds with temperature between 0 – 16 °C were predominantly plate, needle-column, capped-column, dendrite and irregular. Ice crystal habits were affected by the cloud top temperature (CTT), which differed with the changing CTT. Plate and needle-column were predominant habits as CTT was warmer than -8 °C while dendritic and capped-column crystals were observed just as CTT was colder than -13 °C and -18 °C respectively. At the same time, ice crystal habits were also affected by their locations in cloud, since there were a lot of heavy rimed crystals in embedded convective regions. Above the melting layer, ice particle grew mainly by deposition, riming and aggregation processes. The riming process became more intense in lower cloud layer due to the increase of super-cooled liquid water content. The broadening rate of particle size distributions (PSDs) is obviously different between embedded convections and stratiform clouds in the vertical direction, at levels of 4.8–4.2 km (-11.6– -8 °C), the PSDs broadening rate in embedded convections is 3 mm km-1, smaller than 3.67 mm km-1in stratiform clouds, but at levels of 4.2–3.6 km (-8 – -5 °C), the PSDs broadening rate in embedded convections is 6.67 mm km-1, which was almost three times as fast as 2.33 mm km-1in stratiform clouds, which was mainly due to the fact that embedded convections had more super-cooled liquid water than stratiform clouds at levels of 4.2–3.6 km. (Zhu Shichao, Guo Xueliang)

1.3 A 35-channel microwave radiometer for prof ling atmospheric temperature and humidity

The design principles and main characteristics of the MWP967KV ground based 35 channel microwave prof ling radiometers are presented. The prototype radiometer is a compact integration of dual band (K and V) broadband radiometry antennas, two receivers, a synthesized local oscillator, a surface meteorological sensor, and a power supply in a cabinet. It has the capability of detecting down-welling atmospheric thermal emission continuously on a minute time scale. Several levels of observed data are composed and regulated. By using BP artif cial neural network retrieval algorithms, the radiometer is capable of retrieving the vertical distributions (profiles) of atmospheric temperature, water vapor, relative humidity, and other variables in real time. The retrieved prof les range from the surface up to 10 km in 58 layers. The radiometer was used in atmospheric observation in Beijing in autumn to winter of 2012 for about two months. The data of 69 radiosonde cases are gathered to evaluate the radiometer’s performance. The accuracies of dual band atmospheric bright temperature values are analyzed. The retrieved temperature and humidity profiles are analyzed as well, and the mean difference, root mean square difference, and correlation are calculated. The statistical results indicate that the radiometer has the ability to support real time weather surveillance, being internationally advanced. (Lu Jiangping, Huang Jiangping, Guo Xueliang)

1.4 Discriminating a cloud area by using L-band sounding data

L-band sounding data recorded from January 2008 to December 2009 and corresponding spatial and temporal CloudSat data are used to analyze the cumulative frequency distributions of relative humidity in and near clouds. It is determined that the accuracy of cloud discrimination can reach 81% against a relative humidity threshold set at 75%. In addition, various thresholds of relative humidity for discriminating clouds are evaluated on the bases of bias score (BS) and threat score (TS). By setting the relative humidity at 81%, the highest TS score of 0.66 is achieved. Moreover, relative humidity thresholds at various heights are also analyzed on the basis of BS and TS. The results show that the relative humidity threshold with the highest TS score at the same cloud height decreases when the height increases. The TS score of the discriminated cloud area with these thresholds for corresponding altitudes is higher than 0.6, and the accuracy is more than 84%, which is signif cantly better than that obtained by using a single relative humidity threshold for all heights. Finally, with these thresholds being optimized, a method of discriminating the cloud vertical structure is proposed by using L-band sounding data. (Cai Miao, Ou Jianjun, Zhou Yuquan)

1.5 Observation, analysis, and hail-forming area identif cation of a super-cell hailstorm

A detailed analysis on the evolution of stream fields and echo structures of a super-cell hailstorm that occurred on April 17, 2011, is conducted on the basis of Doppler radar data combined with radio sounding and surface observations. The main results are as follows: The hailstorm occurring in a conditional instability and signif cant vertical wind-shear environment was classif ed as a right-moving storm. A cross-section of the development stage shows that an organized updraft was formed gradually, which promoted the formation and development of the hail cloud. During the hail-forming stage, a strong, tilted updraft and deep meso-cyclone emerged in the hailstorm; the main updraft corresponded to the weak echo region. The hailstorm maintained a typical bounded weak echo region (BWER)-overhang echo-wall echo structure. According to the evolution of zero velocity line, which connects the radar radial velocity and the speed of hailstorm, the line approached the overhang echo zone with the developing hail cloud and crossed the overhang echo. The trend of zero velocity line was upturned, and the collection power of the cave channel near the line was suff ciently strong to form hail. The hail formation area can be analyzed through the determination of the zero velocity line. A method of identifying the characteristic structure of the hail-forming region is also presented in this study. According to the strong echo dislocation of high and low levels, the characteristic structure is determined quickly and accurately from the strong echo center section at two heights. Moreover, a 45 dBz region at a 6 km height above the 0 °C layer is identif ed as a hail-forming region, where the potential of hail is calculated to be 100%. The identif ed hail region is in good agreement with the actual hail observation. (Cai Miao, Zhou Yuquan)

1.6 Observational studies of distribution characteristics of supercooled cloud water during a westerly trough process

The growth and evolution of supercooled water are always a concern in the cloud physics and weather modification science. Based on the hypothesis proposed by Hobbs in 1974, a westerly trough in Hebei Province on 21 September 2012 is analyzed by using the airplane observation, satellite monitoring, radar monitoring, and other regular observation data. Results show that (1) a wide and thick area of supercooled water exists in front of the trough where the supercooled water is abundant, the concentration and root mean cube diameter of the forward scattering spectrometer probe (FSSP) are relatively of high value, and the cold cloud is thick without dry layers or warm cloud; (2) as the trough draws near, the cloud near the trough develops rapidly, the concentration and depth of the area of the supercooled water increase signif cantly, the cloud becomes thicker with dry layers, the liquid water content (LWC) in cold and warm cloud is abundant, meanwhile the concentration of 2DC and 2DP is of high value, and the mesoscale structures move quickly; (3) in the rear of the trough, the root mean cube diameter of the droplets and the amount of the supercooled water are remarkably small, and the height and width of the supercooled water decrease a lot, although the cloud concentration is still high, the cold cloud is very thin with a dry layer between warm cloud and cold cloud, and the warm cloud has several layers with a high value concentration of 2DC and 2DP. The precipitation is produced by the warm rain process. Usually the peak of the LWC stays over the temperature inversion layer. The results based on the analysis of the particle measurement system (PMS) data are well consistent with those based on the satellite and radar monitoring data.（Zhou Yuquan, Sun Jing）

2 Cloud physics and artif cial seeding simulation researches

2.1 A case study of aerosol impacts on summer convective clouds and precipitation over North China

The emissions of greenhouse gases, precursor gases and particulate matters may directly alter the Earth radiative budget or indirectly modify cloud and precipitation processes, and possibly induce changes in climate and the hydrological cycle at the regional to global scale. The previous publications reported a few quantitative assessments and inconsistent results on the effects of the emissions on cloud and precipitation. The aerosol properties and possible impacts on a convective precipitation case on 4 July 2008 over the urban region of North China are investigated based on the Moderate Resolution Imaging Spectroradiometer (MODIS) data and the Weather Research and Forecast (WRF) model coupled with Chemistry (WRF-Chem). Results show that the Aerosol Optical Depth (AOD) is over 0.9 in the study area, indicating a high concentration of aerosol pollution. The value of Angstrom exponent in the study area is larger than 1.0, indicating that the main particles in the area are industrial and biomass burning pollution aerosols with a radius of less than 0.25–0.5 μm. The modeling results show that the domain-averaged precipitation amount under polluted conditions can be increased up to 17% during the whole cloud lifetime. However, the maximum rainfall rate above 30 mm h-1is enhanced, whereas that below 30 mm h-1is suppressed in most cloud lifetime. The differences of cloud microphysics and dynamics between polluted and clean conditions indicate that both warm and ice microphysics and updraft are suppressed at the storm,s initial and dissipating stages, whereas those at the storm,s mature stage are obviously enhanced under polluted conditions. (Guo Xueliang)

2.2 Theoretical research on AgI seeding simulation of the decreased convective rainfall

After two prognostic variables are added, An AgI seeding scheme is coupled with a three-dimensional cloud model, considering four nucleation modes. A case of heavy convective rainfall is simulated using this model. Numerical seeding experiments of releasing AgI in cloud are simulated to study the possibility to decrease the heavy convective rainfall. Several tests of different locations and different concentrations of seeding particles are designed. Results show that over-seeding in an updraft area with supercooled water can not only reduce the amount of rainfall, but also reduce the maximum rainfall strength. With 2×108kg-1seeding concentration, rainfall amount can be decreased up to 32%, which greatly lowers the possibility of causing f ood. After seeding with large amounts of AgI, numerous AgI particles are nucleated, and these ice particles consume much supercooled water. The falling speeds of graupel and raindrops become weaker after seeding. The decrease of melting amount of graupel to rain in seeding cloud causes the decrease of rain amount, and later the much more evaporation of rain causes less rainfall amount. Results show that condensation freezing and immersion freezing are the dominant nucleation modes in this convective cloud. The over-seeding methods in this research are able to be used in a f eld operation. (Lou Xiaofeng, Sun Jing, Shi Yueqin, Zhang Xing)

2.3 Effects of underlying surface on the formation and evolution of hail cloud

A severe hailstorm in Beijing on 31 May 2005 was simulated using mesoscale model WRF and compared with the observed radar echo, hailstorm moving path and hail fall area. The effects of underlying surface of cities and farmland on hailstorm was investigated. The results show that due to the effect of Urban Heat Island （UHI）, the sensible heat f ux is obviously increased, which is favorable for the development of hail cloud and enhancement of vertical velocity and formation of larger-sized hailstones, and the increase of the surface accumulated hail fall. But the inf uence of urban surface on the moving path on hail cloud is smaller. The farmland surface has larger latent heat f ux and higher evaporation, which is favorable for the formation of a large amount of smaller-sized hailstones, and induces weak vertical velocity and small mean diameter of hailstones in the cloud. The surface accumulated hailfall decreases due to the weakening intensity of hail clouds for farmland surface. (Guo Xueliang)

2.4 Numerical simulation of a convective stratiform mixed cloud precipitation at different scales

The precipitation of a convective stratiform mixed cloud in Zhangjiakou during 18–19 April 2009 is simulated using the mesoscale numerical model WRF-ARW (V3.2) and comparatively analyzed with the observation data at different scales. Results show that the west wind trough at 700 hPa and the low vortex at 850 hPa are the main weather systems responsible for convective stratiform mixed cloud. The warm wet air from the southern China and the low vortex from northwest Inner Mongolia are main water vapor suppliers, which converge in Zhangjiakou region and thus are conducive to cloud system development and precipitation formation. The cloud system shows a NE-SW banded distribution, which is 1000 km long and 300 km wide, and has lots of cloud water centers, covering tens of kilometers. The cloud system has the echo characteristics of typical convective stratiform mixed cloud precipitation, such as columnar echo of cumulus cloud embedded in a uniform echo layer. The cross-section of radar echo shows that the cloud water content is heterogeneous either horizontally or vertically. The centers of rainwater are corresponding with the centers of graupel and snow in the upper layer, with a horizontal range of 10–20 km. (Zhang Wei, Zhou Yuquan)

2.5 Numerical simulation and f ight observation of stratiform precipitation clouds in spring in Shanxi Province

The CAMS meso-scale cloud model was introduced and operationally applied in Shanxi Province in 2009. The macro and micro structure of stratiform precipitation clouds, especially the vertical micro-physical structure are simulated and analyzed of a spring stratiform precipitation process in Shanxi Province on April 20th, 2010 by using this model. Two times of cloud physical detection flights are carried out by using a weather modif cation plane equipped with Droplet Measurement Technologies (DMT) in the same place during the same period of that day. The data and images from f ight detection and the results of numerical simulation are compared and studied. Simulation results show that the precipitation process mainly comes from cold stratiform cloud. The cloud contains a lot of supercooled water, and the thickness of the rich supercooled water layer is about 4000 meters. The temperature of the supercooled layer was 0– -40 °C, and the ratio content of the supercooled cloud water is 0.1–0.7 g kg-1with some ice crystals distributed unevenly. The structures of the stratus precipitation cloud can be roughly divided into three layers. The f rst layer (upper layer) is mainly composed of ice crystals; snow, sleet, and supercooled cloud water is mixed in the second layer (middle layer); and the third layer (lower layer) is mainly of liquid raindrops. The vertical distribution and the transformation of different hydrometers in different stages of the precipitation are analyzed. The precipitation mainly comes from the melting of the ice phase particles such as ice crystals, snow, sleet and the transformation of liquid cloud droplets. A comparison of the numerical simulation results and the plane observation shows that the relationship between temperature and altitude is in good agreement. The simulated vertical structure of the different cloud particle phase and the vertical distribution of the cloud liquid water ratio content are nearly the same as the vertical distribution of different cloud particle images and the cloud liquid water content of the f ight detection. The difference is that the simulated height where various hydrometeors appear is higher than the actual f ight detection. (Tao Yue, Shi Yueqin)

3 Research on technology of weather modif cation

3.1 Study of antiaircraft-gun, plane and rocket cloud seeding diffusion and operation designing

This article gave out the diffusion law of different seeding ways such as antiaircraft-gun, rocket and plane, based on the analytical solution of cloud seeding agent diffused in cloud, by the diffusion calculation model of point source, multi-line source and mobile point source. It studied the diffusion law and effective range of different seeding ways and examined the calculation scheme by using a f ight seeding track caught by a satellite, and discussed such problems as adequate seeding f ight designing. The main conclusions were as follows: As a point source, when using a single antiaircraft-gun for work, the operation range was only 0.5 km, it would be better to use multi-shell for keeping concentration and diffusion range, the work effect can be improved largely when nucleation rate was raised. The work of rockets and planes was calculated as a line source, the widths beyond threshold value 1 h after seeding were about 7 km and 6.6 km, which could be taken as a reference for the multi-line seeding f ight interval. Due to the effect of wind, the diffusion areas would disperse or overlap when using ‘S’ seeding way. The best f ight design which could make the target area get adequately seeded was a ‘8’shaped f ight route. The cloud seeding diffusion calculation and work designing software developed based on diffusion calculation model could calculate the diffusion range, concentration and evolution by time of agents released from a plane, an antiaircraft-gun and a rocket in real work, and could design the seeding ways for effective work in different target areas. The results, which were direct and clear, helped with the actual work application and seeding diffusion calculation as a guidance to weather modif cation in our country. ( Zhou Yuquan)

3.2 Evaluation of precipitation enhancement and hail suppression programs in Beijing region

Seeding effects investigation or evaluation is one of the most important parts of weather modif cation. It also acts as a crucial standard of assessing the scientific and technological level of weather modification activities, and plays an extremely important role in promoting the development in this connection. Taking into account the activities implemented in Beijing region in recent years, we assessed the seeding effects of precipitation enhancement and the economic benef ts of hail suppression between 2004 and 2010, based on the classical method of historical regional regression and the agricultural disaster data collected around the whole region. The results indicate that: (1) in the assessment period from May to September, the average ratio of precipitation enhancement efficiency tends to stand at about 20 percent with the sample numbers being accumulated year by year. In the target area selected, cloud seeding totally increased the precipitation amount by 417.8 mm during the 7 years. The statistical seeding effect is of high signif cance; and (2) the estimated average annual economic benef t of hail suppression is nearly 248 million yuan. The average cost-benef t ratio is about 1:16. The highest and the lowest economic benef t appeared in 2009 and 2005, with a corresponding cost-benef t ratio of 1:27 and 1:6, respectively. The methods studied for seeding effects evaluation and results help to strengthen the exploitation and utilization of cloud water resource in a scientific and technological sense in Beijing and its neighboring regions, which f rmly supports the approval of local disaster prevention and mitigation projects as well. (Li Hongyu)

3.3 Research on and application of a method to evaluate the effectiveness of convective cloud

precipitation enhancement

The reliability of convective cloud-seeding effectiveness evaluation is poor when a traditional statistical test method is used because of its large spatial and temporal variation. The f oating-target area method, a new one proposed by Woodley, is introduced, which is based on radar echoes. Some changes are made to this scheme taking into account Tianjin’s terrain and weather modification operation characteristics. The radar based data are used to determine the floating target cell recognition and tracking methods, then determine the catalytic units and control units in the floating target cells; the physical parameters and the retrieved precipitation of each unit are recorded, and the precipitation enhancement effect is calculated to provide physical evidence on artif cial rainfall. The method is used to evaluate the effectiveness of convective cloudseeding on 24 July 2011 in Tianjin, for example, and the objective evaluation results are obtained, which show that: the value of the maximum echo intensity and echo top height increased as the catalyst got into the clouds. It proves that artif cial catalysis takes effect in precipitation enhancement. The effectiveness of precipitation enhancement is 7.69% at a signif cance of 0.043. (Li Hongyu)

4 Progress in weather modif cation

4.1 National Weather Modif cation Development Plan (2014–2020)

In December 2014, National Weather Modif cation Development Plan (2014–2020), formulated by CMA Weather Modif cation Centre, was jointly issued by NDRC (National Development and Reform Commission) and CMA (China Meteorological Administration). The plan identif es the guidelines, goals, overall layout, main tasks and implementation arrangements of the nationwide weather modif cation prorgam, and also proposes an organization, management and operation mechanism for weather modification work. The plan serves as a program of action for nationwide weather modif cation at present and in the near future, and is of guiding signif cance to weather modif cation modernization and its scientif c development. From October to November of 2014, National Weather Modif cation Operations Development Guidance, Weather Modif cation Dedicated Technology and Equipment Management Regulations were formally issued by CMA, marking that China’s weather modif cation operations and equipment are managed by standards. (Chen Tianyu, Zhou Yuquan, Fang Wen)

4.2 Northeast Regional Weather Modif cation Capability Building project

The year 2014 showed signs of benefits in the project of Northeast Regional Weather Modification Capability Building. Within one year, primary design revision and approval were completed; the f rst Xinzhou 60 artif cial rainfall aircraft f nished its test f ight and made its debut in the 10th China International Aviation & Aerospace Exhibition; the third high performance artificial rainfall aircraft was completed in overall design, with 11 sets of airborne equipment having been selected; regional aircraft operation support center started its construction; main features of control system were deployed in the four northeastern provinces; the procurement was finished for high performance operation of aircraft satellite communications system, including 79 GPS/MET devices, 3 X-band Doppler weather radars, GPS/MET data processing center software system and all the devices for external field test areas; training classes were held for weather modification frontier technology & aircraft operations. The initial fruit of the project has played an important role in drought relief and rainfall enhancement efforts in the Northeast China region. (Li Jiming，Chen Weihong)

4.3 The Collection and Processing System of Weather Modif cation Operation Information OICPS V1.0 being in operational use

Based on years of professional work, the OICPS V1.0, part of Weather Modification Centre (WMC) Operational Control System project, was accepted by experts on 21th May. The OICPS V1.0 is the second operationally accepted system following the weather modif cation forecast model system. The OICPS V1.0 composes two parts, a real-time upload system and information acquisition & processing system. Relying on the national meteorological network, it makes it possible for the national weather modif cation operating information to be uploaded, collected, monitored, stored, displayed and managed. A variety of basic data, including information on stations, operations, practitioners and ammunitions, are integrated to offer timely and reliable information for effectiveness analysis and evaluation, joint guidance to an operation and production of decision services. Since the system’s running, the uploading of operation data has been effectively improved, the strength of WMC capability in guidance and service has been enhanced as a strong support to all other operators in control and evaluation. (Wang Fei, Yang Lianying, Li Kangkang)

4.4 Geostationary satellite-based retrieval system for cloud precipitation characteristics in weather modif cation (CPPS-GSSL 2.0) was put into operation

With many years of efforts, Weather Modif cation Centre of CMA developed the geostationary satellitebased cloud characteristics retrieval system (CPPS-GSSL 2.0), which was accepted in a technical review organized by the Department of Disaster Alleviation, CMA. The conclusion has been published and notif ed: the retrieved products are open to operational use.

The retrieval system (CPPS-GSSL 2.0) is based on FY-2 series geostationary meteorological-satellite and L-band sounding data and their real-time retrieved cloud characteristics related products such as Tbb, cloud top height, cloud top temperature, supercooled layer thickness, cloud optics thickness, cloud particle effective radius and liquid water path. By comparing with MODIS retrieval parameters along with a physical analysis of CloudSat cloud-radar, weather radar, raindrop size distribution and ground precipitation data, the accuracy and the usability of the system have been examined. The retrieval products have been used smoothly in all the provinces throughout China as a technical support to multi-regional cloud seeding, forest-grassland f re extinguishing and rain suppression for important social activities. (Cai Miao, Zhou Yuquan)

4.5 The successful weather modif cation for opening and closing ceremonies of the 2014 Second Summer Youth Olympic Games

On August 16 and 28, 2014, the opening and closing ceremonies of the Second Summer Youth Olympic Games were held in Nanjing Olympic Sports Center. In order to ensure the smooth ceremonies, the organizing committee raised the need to carry out cloud seeding tests and services. Meteorological Bureau of Jiangsu Province invited the Weather Modif cation Centre of the CMA (WMCMA) to guide the relevant tests and services for the whole operations, with rainfall obviously suppressed. In the opening ceremony, the precipitation at the stadium is about 2 mm, while the average precipitation around it is 5 mm. The numbers in the closing ceremony are 0.2 mm and 0.68 mm. The operations ensured the success of the ceremonies. The preliminary summary of the key technical work mainly includes:

(1) Based on the analysis of the characteristics of the cloud precipitation and the weather in Nanjing in August, the WMCMA put forward and guided the technical scheme for the weather modif cation for the ceremonies, including the intensive monitoring, the communication command, the layout design of operations, implementation organization and so on.

(2) Thanks to the numerical prediction model for the weather modification operation conditions the WMCMA developed, the catalytic principle and scheme were given 24 h in advance. Combined with the weather forecast and the monitoring of the actual situation, a real-time interaction between the WMCMA and Youth Olympic Command Center was maintained for the discussion on and the revision of the scheme and the estimation of the result.

(3) The Cloud and Precipitation Precision Analysis System (CPAS) developed by the WMCMA was transplanted to establish a command system of rain decreasing operation for the Youth Olympics. The realtime precision analysis of the macro and micro structures of the cloud and the evolution of the precipitation, recognition and discrimination of the operating conditions, the rolling correction of the optimal design for the operation, the real-time command of the multi-catalytic (plane and rocket) by satellite, radar, sounding and many other special instruments were realized.

(4) Thanks to the transplanted CPAS platform and operation command system, planes were used to do the periphery reconnaissance for the pre-operation and for the highly dense rocket based catalytic operation in the adjacent zones. The clouds that were moving towards the venue were successfully weakened, which proved the technical principle and the design before the operation, with expected effects being observed (Fig. 1). （Zhou Yuquan, Liu Siyao, Pu Meijuan, Hu Zhijin）

4.6 National weather modification (WM) operational platform plays an important role in WM guidance and service

National weather modif cation (WM) operational platform was developed by Weather Modif cation Center (WMC) in 2014. The platform mainly includes 4 parts. First part is to transfer, collect, store and manage information for real time use, such as meteorological observation data, WM special observation data, WM seeding data and ground operation data, based on which a database of case studies is developed. Second part is to process, verify and test products. By synthesizing various data, WM characteristic cloud and precipitation variables are produced to be used to forecast and warn seeding potential conditions. Third part is WM operational guidance and service, including forecasting seeding potential conditions, early warning, designing f eld seeding scheme, monitoring and commanding, and seeding effect evaluation and so on. The last part is to share various WM products by website to be used by relevant professionals.

The operational platform plays an important role in real time weather modif cation service. For example, a video consultation was held together by CMA-WMC, Northeast Regional-WMC, Heilongjiang Weather Modification Office, Jilin Weather Modification Office, Liaoning Weather Modification Office and Inner Mongolia Weather Modification Office in April 2014. In this consultation, the structure of cloud system and distribution of cloud band, supercooled water and ice particles in the northeast of China were analyzed. The seeding time, area, and height of rain enhancement were also discussed. The Northeast Regional-WMC arranged the inter-provincial joint operation according to rain enhancement demand. All of these marked the beginning of the operation model which features joint actions through a level-based guidance. As a result, weather modif cation is improved in science and in benef t (Fig. 2). (Zhou Yuquan, Shi Yueqin, Sun Jing, Cai Miao, Liu Weiguo, Tao Yue, Wang Fei）

4.7 Optimizing the evaluations of air cloud-water resources

As a result of continuous research and experiment during 2011–2014, Weather Modif cation Centre of CMA developed and improved the monitoring evaluation method for cloud water resources (CWR-MEM). The method is based on the atmospheric water vapor budgeting equation, clarifying the concept of atmospheric water substance including hydrometeor. It improved the calculation equation and concept of water substance mass, precipitation effectiveness and update period etc. It proposed such new concepts as cloud water resources, aggregation of cloud water resources and effective cloud water quantities.

In 2014, Weather Modif cation Centre of CMA organized the technical forces to optimize the evaluation methods of diagnosis and identification of three-dimensional water and cloud field, temporal-spatial scales and the processing of complex area boundaries. China was divided into f ve areas by longitude and latitude and by climate. 2007–2008 CloudSat’s observation data were used to count the relative humidity threshold, typical liquid water content values and their vertical distribution of each diagnosed cloud field. The height coordinate was changed into temperature coordinate, which made the cloud field concept more accurate, sharply optimizing the diagnosis scheme of three-dimensional cloud and water f eld in each area. To evaluate the cloud water resources, it is desirable to take six weather modification areas into consideration, before subdividing each area into six sub-areas, the borderline of which is made a loop curve with the resolution at 1°. This improves the calculation of condensation and evaporation values, including the integral resolution and accuracy.

The 2014’s cloud water resources monitoring report was prepared using the optimized CWR-MEM scheme with which the cloud water resources in six weather modification areas throughout China from 2008 to 2011 were evaluated. The results are as follows, from 2008 to 2010, the gross quantity of vapor in China was averaged around 36900 billion tons of which 33100 billion tons was input from the boundaries while evaporation was averaged around 3750 billion tons. The gross quantities of hydrometeor (GQh) were averaged at 7150 billion tons. The total precipitation volumes were averaged at approx. 5020 billion tons. Gross cloud water resources were averaged at 2130 billion tons whilst cloud water resources at 1230 billion tons. Annual water vapor precipitation effectiveness was averaged at around 14% while effectiveness of the hydrometeor precipitation was 70%. The update period for the vapor was averagely about 10 days and 7 hours for the hydrometeor. It can be concluded that the cloud water resources differ distinctly in temporal-spatial distribution. (Zhou Yuquan, Cai Miao)

4.8 Evaluation techniques and methods for cloud seeding effect

Based on the detailed analysis of the information from weather modification operations in the whole country, the specif c rain enhancement requirements in different regions are revealed. Four kinds of methods have been developed and integrated to evaluate the effect of nonrandomized rain enhancement operation, and the relevant testing algorithms of the signif cance level have been researched and developed as well. These algorithms have been applied in Jiangxi, Yunnan, Hainan, Chongqing and Anhui provinces. The Doppler radar identif cation, tracing and testing algorithms have been developed based on TITAN techniques and the physical evaluation methods based on regular radar data, which have been applied in the piloted provinces. Typical cloud seeding examples in 2013 in the piloted provinces have been analyzed and tested, and the evaluated effects as well as the statistical signif cance levels have been released. The regional correlation analysis has been made based on the historical rainfall data in the piloted provinces, which is useful for the theoretical accumulation in the f eld of rain enhancement operation and effect evaluation. According to the analysis of the synoptic systems and historical operations in the piloted provinces, as well as the regional correlation analysis, a designed mapping of the target areas and control areas for the cloud seeding in these provinces has been proposed. The summary report 2014 of rain enhancement effect evaluation in China has been prepared.（Yao Zhanyu）

4.9 The development of eff cient seeding agents for warm and cold cloud, and testing, assessment and trial of new devices

The Weather Modif cation Center (WMC) of CMA developed three types, WMC-IN-001, WMC-IN-002 and WMC-CN-001, of cloud seeding f are agents, tested their nucleation rate in cloud chamber, and compared them with those f are agents used in recent rain-enhancement operation. The result shows that the nucleation rates of WMC-IN-001 and WMC-IN-002, which are for cold cloud seeding, are higher by one order of magnitude at least than those used in operation. Under different wind speeds, the particle spectrum of WMCCN-001, which is hygroscopic type seeding agent, is tested in a wind tunnel. The result shows that the number concentration of particles whose diameter is more than 2 m is up to 101. The above three cloud seeding agents have been recognized by the Department of Science & Technology and Climate Change of CMA.

WMC carried out the trial use of hygroscopic f are for warm cloud in Fujian, Anhui and Hebei provinces, for ground smoke stove in Fujian and Anhui provinces, and for airborne flare in Hebei Province. Working jointly with Shanghai Material Management Division of CMA, WMC tested the nucleation rates of airborneand ground-flare, and flare bomb. A review of product design and operation oriented trial plan for “the remote control system for DF37 mm anti-aircraft guns”produced by Suizhou Dafang Precision Mechanical Engineering Co. Ltd. and “HY-1 type airborne f ame strip seeding system”produced by China cloud company was organized. (Fang Wen, Dang Juan, Fang Chungang, Su Zhengjun, Wang Xiaobin, Liu Xijing)