| 刘雯,李建刚,杨莲梅.2016年夏末南疆地区中尺度对流系统(MCS)活动特征[J].沙漠与绿洲气象,2017,11(4):9~16 |
| 2016年夏末南疆地区中尺度对流系统(MCS)活动特征 |
| Characteristics of the MCS over southern Xinjiang During the Late Summer of 2016 |
| 投稿时间：2017-04-01 修订日期：2017-05-18 |
| DOI：10.12057/j.issn.1002-0799.2017.04.002 |
| 中文关键词: 中尺度对流系统 南疆地区 时空分布 生命史 日变化 |
| 英文关键词:MCS southern Xinjiang spatial-temporal distribution diurnal variations |
| 基金项目:中央级公益性科研院所基本科研业务费专项资金项目(IDM2016001)，国家自然科学基金项目（41565003），科技部公益性行业科研专项(GYHY201506009) |
|
| 摘要点击次数: 949 |
| 全文下载次数: 850 |
| 中文摘要: |
| 2016年夏末南疆地区短时强降水天气频发，中尺度对流系统活动频繁。利用强降水频发时段2016年8月8日至9月16日逐时FY-2G红外亮温（TBB）资料对南疆地区中尺度对流系统（MCS）进行分析，共获得92个生命史≥3小时的中-β尺度对流系统（MβCS），包括β中尺度对流复合体（MβCCS）和β中尺度持续拉长状对流系统（MβECS）。根据南疆地区的极端干旱气候背景，本文中-β尺度对流系统的尺度判定标准为云顶亮温（TBB）≤-32℃的连续冷云区直径≥20 km。对MCS的分布和活动特征进行了分析，结果表明：圆状MCS和带状MCS发生的频次相当。天山南坡和昆仑山北坡是MCS活跃区，MCS移动方向主要以偏东或东北方向为主，南疆地区活动最频繁的MCS生命史为3～4个小时。南疆地区MCS具有明显不同的日变化特征，午后和傍晚是MCS最活跃的时段。与MβCCS相比，MβECS具有更明显的夜发性特征。昆仑山北坡MCS的最活跃时段早于天山南坡MCS，而天山南坡MCS夜间和凌晨形成的特征更为显著。生命史为3～5小时的短生命史MCS主要在午后和傍晚形成发展，并在形成后2小时达到成熟，生命史超过6小时的长生命史MCS多发于午后和凌晨，并且其发展阶段更长。本文给出了1个引发短时强降水的MβCCS和1个MβECS的云团演变特征。 |
| 英文摘要: |
| During the late summer of 2016 over southern Xinjiang short-time heavy rain occurred frequently. Mesoscale convective systems occurred frequently. Based on the FY-2G TBB(equivalent temperature of black body)dataset during 8 August-16 September 2017，the 92 MCSs (Mesoscale Convective Systems) including MβCCS(Meso-β Circular Convective System) and MβECS(Meso-β Elongated Convective System) with life-cycle greater than 3 hours were analysed over southern Xinjiang. According to the extreme drought climate background in southern Xinjiang, the scale of meso-β-scale was defined as that the diameter of cold cloud continuous area of TBB value≤-32℃ is more than 20km in this paper. The temporal and spatial distributions and active features of the MCSs were analysed. The results indicate that the frequency of MβCCS and MβECS is about the same. The southern slopes of Tianshan Mountains and the northern slopes of Kunlun Mountains are main active MCS areas. Eastward, northeastward are the main moving directions for MCSs. The modal duration of MCSs over southern Xinjiang was about 3～4 hours. The diurnal variations of MCS over southern Xinjiang were obviously different. The peak time for MCS initiation is around afternoon and nightfall. MβECS had a nocturnal occurrence characteristic compared with MβCCS. The active periods of the MCSs over the northern slopes of Kunlun Mountains were earlier than the southern slopes of Tianshan Mountains. MCSs over the southern slopes of Tianshan Mountains had a nocturnal occurrence characteristic. Short life MCSs formed and developed in the afternoon and evening, and matured after 2 hours. Long life MCSs formed in the afternoon and morning, and had a longer development stage. Finally, one MβCCS causing rainfall and one MβECS were presented. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |