上海城市大风时空分布特征及基于实时灾情的影响分析

Spatiotemporal characteristics urban gales in Shanghai and correlative impact analysis based on real-time disaster data

利用2008—2019年上海市自动站小时极大风速数据和上海市应急联动平台的实时大风灾情数据,分析了上海城市大风和灾情的时空分布特征及联系,探讨了上海城市大风的影响。研究表明:1)城市大风及致灾呈现明显的季节变化,8级大风日、极大风速和灾情变化都呈现夏季单峰型。夏季大风日占全年的41%,大风灾情占全年的80%以上。大风灾情的年际变化波动较大,主要是受极端天气影响。2)城市大风及致灾体现出明显的城郊差异:受城市化影响中心城区风速明显偏小;灾情密度在中心城区最高(可达37件/km^(2)),在区域中心及副中心也相对偏高,各区灾情数和人口、GDP都呈正相关关系;房屋类承灾在中心城区和周围区域相对突出,在崇明区最不明显。3)城市致灾大风天气可分为江淮气旋大风、雷雨大风、热带气旋大风和冷空气大风4类,其中雷雨大风发生最频繁,热带气旋大风的致灾程度最严重。4)树和车辆是最突出的大风承灾体,其次为电线和雨棚。大风致灾具有明显的链式反应。

In recent years,global warming has intensified extreme weather and climate events,significantly impacting urban areas.Shanghai,located in the eastern coastal region of China,is increasingly vulnerable to weather-related disasters.As a megacity,its urban operations are heavily influenced by these events,particularly gales,which pose severe threats to both infrastructure and public safety.Despite their impact,research on gales in Shanghai has been limited by incomplete and inconsistent disaster data.Since 2007,the Shanghai Emergency Response and Coordination Center has shared weather-related alarm data with the Shanghai Center for Meteorological Disaster Prevention Technology.This data includes detailed information on the timing,location,and nature of disasters,enabling a more thorough analysis of the impacts of weather events on the city.Using hourly maximum wind speed data from Shanghai's automatic stations and real-time gale disaster data provided by the Shanghai Emergency Response Coordination Center from 2008 to 2019,this study analyzes the spatiotemporal distributions of urban gales and their correlations with disasters.The findings are as follows:1)Gales and disasters exhibit significant seasonal variations,with force 8 gale days,maximum wind speeds,and disaster occurrences all peaking in summer.Summer gale days account for 41% f the year,and gale-related disasters constitute over 80%of the total.Inter-annual fluctuations in disasters are pronounced,primarily influenced by extreme weather events.2)Differences in gales and disasters are evident between urban and suburban areas:Ⅰ)Wind speeds are notably lower in downtown regions due to urbanization,while Chongming Island,Hengsha Island,and coastal areas southeast of Pudong experience significantly higher wind speeds due to funnel-shaped terrain effects.Ⅱ)The density of disaster cases is highest in the central city(up to 37 cases/km^(2))and remains relatively high in regional centers and sub-centers,with the number of disasters positively correlated with population density and GDP.III)Housing-related damages are most prominent in downtown areas and their surroundings,while damages to trees and power lines are significant in Chongming District,and vehicle-related damages are prevalent in Jiading District and Songjiang District.3)Gale disasters in Shanghai can be categorized into four types:Jiang-Huai cyclone gales,thunderstorm gales,tropical cyclone gales,and cold air gales.Thunderstorm gales are the most frequent,while tropical cyclone gales are the most severe.Jiang-Huai cyclone gales impact a broad area of the city but are infrequent,and cold air gales are the least severe.4)Trees and vehicles are the most common disaster-affected entities in strong wind events,followed by power lines and rain shelters.Gale disasters often trigger chain reactions.To effectively prevent and mitigate gale-related disasters,it is crucial for the city to develop detailed emergency response plans and enhance cooperation among management departments.Future research should focus on establishing thresholds for gale disasters and creating risk warning products,thereby advancing the city's disaster management capabilities to a more sophisticated and efficient level.