摘要
海岛城市化导致不透水面快速扩展,增加了城市热环境风险。城市热岛安全度评价,在维护海岛城市独特的气候资源禀赋及城市环境规划中起着重要作用。以舟山本岛为例,利用2015年两景Landsat8影像,反演出研究区高温及低温情景中的地表温度,并使用均值-标准差法将地表温度划分冷岛、绿岛、正常区、次热岛及强热岛5个等级。针对舟山本岛城市热岛强度空间差异较大的特征,将城市划分为12个地理子单元。在构建热岛安全度评价指标体系的基础上,使用突变级数法计算了各个子单元的热岛安全度。结果表明:(1)高温情景中强热岛面积比重(17.7%)高于低温情景(12.0%),总热岛面积比重季节差异不大;(2)东港、定海老城、白泉及沈家门受到社会经济因素扰动最大,城市内部热岛安全度最低,展茅、小沙及马岙热岛安全度最高。本研究旨在为岛陆土地资源紧缺的舟山本岛应对城市热环境问题,实现人地系统协调发展,提供理论依据及建议。
Island urbanization has accelerated the expansion of impervious surfaces,increasing the urban risk of the thermal environment.Urban heat-island effect assessment is vital in island climate resource protection and urban environmental management.Our study area is Zhoushan Island,the inversions of land surface temperatures were retrieved from two Landsat 8 OLS images with warm and cold scenarios in 2015.Five degrees of land surface temperatures were divided using the mean standard method,and they include temperatures corresponding to the cold island,green island,normal island,sub-heat island,and strong-heat island.Due to the discretely urban space of Zhoushan Island,the study area is further divided into sub-geographic units.The heat-island safety degree of each sub-region is calculated by the catastrophe theory that based on building the evaluation index system of the heat-island safety degree.There are two results in our study:(1)the proportion of strong-heat island in warm scenario(17.7%)is bigger than that of the cold one(12.0%),but there is little difference in total heat-island proportion in the two scenarios;(2)the intensity of socio-economic disturbance varies in urban sub-geographic units,wherein Donggang,Dinghai,Baiquan,and Shenjiamen have the lowest security degree,while Zhanmao,Xiaosha,and Ma’ao are the safest areas against the heat-island effect.We aim to provide theoretical bases and suggestions for Zhoushan Island to cope with urban thermal environment problems and realize the coordinated development of human-land systems.
作者
樊超
桂峰
赵晟
FAN Chao;GUI Feng;ZHAO Sheng(Marine Science and Technology College,Zhejiang Ocean University,Zhoushan 316022,China)
出处
《海洋科学》
CAS
北大核心
2019年第10期134-141,共8页
Marine Sciences
基金
“全球变化”国家重点研发计划(2017YFA0604902)~~
关键词
海岛城市
热岛效应
安全度
突变级数
Zhoushan Island
heat-island effect
security pattern
catastrophe theory
