【摘要】：利用2013年3月23日-4月22日在福建省廈門市外場觀測得到海霧過程的能見度、霧滴譜、自動氣象站資料及常規(guī)氣象資料和NCEP全球分析資料。主要分析了8次海霧發(fā)生期間天氣形勢和氣象要素對海霧生消的影響；探討了海霧過程的微觀結構特征；研究了海霧微物理過程(核化、凝結和碰并等)的變化特征,并給出了主要特征量的相關性。得到以下主要結論：(1)有利廈門春季海霧形成的天氣形勢主要為三類：冷鋒型、低壓倒槽型、高壓入海型。主要天氣型為冷鋒型,持續(xù)時間最長、最低能見度較低。(2)海霧期間,西南風頻率的顯著增加對海霧的形成有重要作用,低層西南暖濕氣流平流至沿岸冷海面,為海霧的發(fā)展提供了充足的水汽條件。出現(xiàn)海霧時,氣溫明顯下降,廈門海霧對應區(qū)域存在0-1℃氣海溫差。(3)海霧過程中多有逆溫層或等溫層存在,穩(wěn)定的大氣層結阻擋水汽向高空擴散,有助于低層水汽的聚集,對海霧的發(fā)生和維持有重要作用。(4)對比其他地區(qū)海霧,2013年廈門春季海霧的霧滴數(shù)濃度較大,液態(tài)水含量較小。液態(tài)水含量偏小的原因：首先,由于觀測點設在海島沿岸,海上平移的霧會受到海陸不同下墊面和周圍環(huán)境的影響,可能夾卷未飽和空氣團,霧滴蒸發(fā),液態(tài)水含量減�。缓ｌF過程中濃霧階段持續(xù)時間較短,霧滴半徑小,液態(tài)水含量偏�。淮送�,受儀器量程(1μmr25μm)限制,半徑大于25μm的霧滴無法探測。(5)對海霧過程中主要的微物理量(霧滴數(shù)濃度、液態(tài)水含量、平均半徑)相關性分析表明,三者均為正相關,且自動轉化閾值只有在濃霧階段較大,主導的微物理過程為凝結增長伴隨著持續(xù)不斷的核化過程和可逆的蒸發(fā)過程。海霧平均霧滴譜擬合符合Junge分布,呈單調遞減,霧滴主要集中在直徑2-7μm區(qū)段。
[Abstract]:From March 23 to April 22, 2013, the visibility, droplet spectrum, automatic weather station data, conventional meteorological data and NCEP global analysis data of sea fog process were obtained from the field observation in Xiamen, Fujian Province. This paper mainly analyzes the influence of weather situation and meteorological elements on the occurrence and elimination of sea fog during 8 sea fog occurrences, probes into the microstructural characteristics of sea fog process, and studies the variation characteristics of sea fog microphysical process (nucleation, condensation and collision etc.) The correlation of main characteristic quantities is given. The main conclusions are as follows: (1) the weather conditions favorable to the formation of sea fog in Xiamen in spring are mainly divided into three categories: cold front type, low pressure inverted trough type, high pressure entering sea type. The main weather pattern is cold front type, the longest duration and the lowest visibility. (2) during the fog period, the significant increase of southwest wind frequency plays an important role in the formation of sea fog. It provides sufficient water vapor conditions for the development of sea fog. When the sea fog appears, the temperature drops obviously, and there exists 0-1 鈩，

本文編號：2224418