2019-2023年夏季青藏高原闪电时空分布特征研究
网络出版日期: 2025-04-29
基金资助
广西重点研发项目(AB22035016,AB22080104);甘肃省自然科学基金重点项目(24JRRA082);柳州市元宝山地形暴雨重点实验室重点项目(2024ybssysz2);中国科学院高层次人才计划项目(E2290702);国家自然科学基金项目(42330609);西藏自治区科技计划项目(XZ202501JD0022)
Study on Temporal and Spatial Distribution Characteristics of Lightning on Qinghai-Xizang Plateau in Summer 2019-2023
Online published: 2025-04-29
青藏高原海拔较高,闪电和对流活动相较于其他低海拔地区具有一定的特殊性。为了揭示青藏高原地区闪电活动的时空分布特征,基于风云四号A星闪电探测仪Lightning Mapping Imager (LMI)获取的2019-2023年夏季(6-8月)闪电“组”数据,本文对青藏高原地区的闪电活动进行时空分布特征的统计分析。分析结果表明:青藏高原的闪电频次存在显著的地域性差异,频次高值区主要集中在青藏高原的东部、中部(喜马拉雅山脉以北,那曲市及其周边地区)和南部(山南市和林芝市南部)。青藏高原夏季的闪电活动主要发生在6月和7月,其中6月的闪电活动多集中在东部和南部地区;7月中部地区的闪电活动有所增强,东部地区的闪电活动则有向东南部和东北部转移的趋势;8 月东部地区的闪电活动有所减弱,而南部和中部地区的闪电活动则有所增强。在闪电频次日变化上,傍晚和夜晚[18:00(北京时,下同)至次日03:00]是青藏高原闪电活动的高发时段。白天的闪电辐射强度呈现“双峰”特征,大部分时间闪电辐射强度可达到400 μJ·m-2·ster-1以上;夜晚闪电辐射强度则呈现“单峰”特征,辐射强度通常在400 μJ·m-2·ster-1以下,白天闪电辐射强度明显高于夜晚。多数闪电活动的辐射强度小于100 μJ·m-2·ster-1,5年平均数量占比达到 67. 13%。在日变化分布上,青藏高原中部和东部地区的闪电活动趋势基本一致,峰值出现在20:00-21:00和02:00左右,南部地区在05:00-06:00达到峰值。三个地区闪电活动高发月份均为7月,南部地区在8月份相较6月、7月与中部和东部地区相比更为活跃。本研究为进一步理解该地区的气候变化和灾害防御提供了科学依据。
安江浩, 陈 生, 胡泽勇 . 2019-2023年夏季青藏高原闪电时空分布特征研究[J]. 高原气象, 0 : 1 . DOI: 10.7522/j.issn.1000-0534.2025.00039
The Qinghai-Xizang Plateau,due to its high altitude,exhibits unique lightning and convective activity compared to lower-altitude regions. Using the ‘Group’data from the Lightning Mapping Imager(LMI)on the Fengyun-4A satellite,a statistical analysis of the spatiotemporal distribution of lightning activity on the plateau was conducted for the summers(June to August)from 2019 to 2023. The results reveal significant geographical variations in lightning frequency across the Plateau,with high-frequency areas predominantly located in the eastern,central(north of the Himalayas,in and around the city of Nagqu),and southern(south of Shannan and Linzhi)regions. In terms of temporal distribution,lightning activity is most prevalent in June and July. Specifically,June sees concentrated lightning activity in the eastern and southern regions,while July experiences an in‐ crease in the central region and a shift of activity in the eastern region towards the southeast and northeast. By Au‐ gust,lightning activity decreases in the eastern region but increases in the southern and central regions. Regarding the daily distribution,the evening and night hours[18:00(Beijing Time,same as after)to 03:00 the next day]are identified as the peak periods for lightning activity on the Qinghai-Xizang Plateau. During the daytime, the intensity of lightning radiation exhibits a 'double-peak' characteristic,frequently exceeding 400 μJ∙m-2∙ster-1. Conversely,at night,the intensity of lightning radiation generally follows a 'single-peak' pattern,usually remaining below 400 μJ∙m-2∙ster-1. Notably,the intensity of lightning radiation is significantly higher during the day than at night. Most lightning events recorded were less than 100 μJ∙m-2∙ster-1,with a five-year average of 67. 13%. In terms of daily trends,lightning activity in the central and eastern parts of the Qinghai-Xizang Plateau shows similar patterns,with peaks occurring around 20:00-21:00 and 02:00 hours. In contrast,the southern part of the Plateau experiences peak activity around 05:00-06:00 hours. The highest lightning activity across all three regions was observed in July,with the southern region displaying more activity in August compared to June and July,unlike the central and eastern regions. This study reveals the spatiotemporal distribution of lightning activity on the Qinghai-Xizang Plateau,providing a scientific basis for better understanding climate change and disaster prevention in the region.
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