Assessment Of Shenzhen Western Thermal Environment Vulnerability

Urban as the main human physical habitat, provides the material base and living environment for social economic activities. The urban ecosystems and climate especially urban heat environment have been damaged by rapid urbanization recently years. With the fact of global warming and rapid urbanization, heat wave hazards have become much more frequent during the past decades, which strongly threat the health of urban residents. Urban heat environment as the dominant factor of urban environment is directly related to the heat wave hazards. Urban heat environment vulnerability assessment is of great significance for heat wave hazards mitigation and urban sustainable development.Shenzhen as a typical rapid urbanization city in China has been taken as an example in this study. Based on vulnerability assessment theory and heat wave risk characteristics, the index system of urban heat environment vulnerability is constructed. Rule hierarchy is composed of age, personal economic status situation, medical convenience and urban heat environment. Furthermore, age index includes population density aged 5 and below, population density aged 65 and over; personal economic status situation includes residential standard land price, residence area per family and monthly rent per family; least-cost distance model is utilized to calculate medical convenience; urban heat environment is characterized by land surface temperature(LST).ASTER image, data of sixth national census 2010, standard land price etc are utilized to calculate the spatial distribution of rule hierarchy, based on Split-window Algorithm, socioeconomic date spatialization methodology and least-cost distance model. Entropy method and Delphi method are used to determine weigh and calculate Shenzhen western heat environment vulnerability. The result indicate that:(1) Urban heat environment vulnerability in Shenzhen western is medium and the value distribute uniform. Divisional statistics indicate that vulnerability average in south study area.(2) The spatial distribution of heat environment vulnerability hot spots show a aggregative pattern. Heat environment vulnerability hot spots includes: Special Economic Zone(SEZ), Anterior Ocean Zone(AOZ), Longhua center, Aviation City Zone(ACZ), and Western Industry Cluster. Dominant factor analysis of heat environment vulnerability indicates: sensitivity is the dominant factor of heat environment vulnerability in the south of study area because this area live much more extreme heat sensitive people. There are almost no large hospital in the area of Longhua center, so adaptability is the dominant factor. Industrial park, aviation land, port, and logistics land is the main land use patterns in AOZ, ACZ, and Western Industry Cluster which result higher impervious surface area and lower vegetation coverage, so exposure is the dominant factor in the western study area.Therefore, medical conditions improvement are essential for heat-related human mortality mitigation in middle and west area of Shenzhen. Meanwhile, improving residential conditions, strengthen risk perception and enhance extreme heat warning mechanism are of great significance for heat wave hazards mitigation.