Study On Urban Heat Island Effect In The Process Of Urbanization

In recent years,along with the acceleration of urban urbanization,the increase in population and the accelerated expansion of urban areas have led to dramatic changes in the underlying surface of the city,while the urban thermal environment has been affected,resulting in the heat island effect.The volume and density of buildings in the city have also increased,resulting in changes in land attributes,the decline in the proportion of ecological green space and water area,and a series of environmental problems in urban ecology.The urban heat island effect has gradually become a major problem affecting urban development.This paper takes the city as the background and selects HanDan as the research object.Firstly,through questionnaire survey and expert interviews,Urban heat island influencing factors under the background of urbanization can be divided at three aspects: urban density pattern,green land structure characteristics and proportion,and urban expansion.Secondly,based on the building type and density factors,this paper analyze its influence in the heat island effect;Based on the characteristics,location and coverage of the green space,the study analyzes the effects of green space structure,location,and proportion on the cooling of heat islands and the analysis is divided into three levels: surface temperature,heat island intensity and temperature interval.Thirdly,the influencing factors of these three aspects are quantitatively analyzed through inversion,classification and simulation processing.It can be possible to conclude that the regions with high similarity and higher density have higher heat island effect,and the high-rise buildings have better energy exchangeability.What's more,There is a good correlation between the proportion of green land and the intensity of the heat island.The increase of the area of forest land and water area and the decrease of solid ground will make the effect of “cold island” of green space more obvious.The green space has a logarithmic change in temperature regulation trend;Urban development will expand the heat island intensity areas,which are linked to the city's center of gravity and development direction.Finally,based on the above three factors,the paper gives the corresponding heat island mitigation measures.In terms of construction,more architectural forms such as point-type high-rise or multi-storey building density can be used to reduce the building density of the newly built area;In terms of green space and water,the proportion of green land is increased.The urban center adopts decentralized and three-dimensional greening,and at the same time increases the number of large park green spaces in areas with more serious heat island effects;In terms of the development of urban expansion,the green space is arranged in advance in the direction of urban construction or urban center to reduce the impact of the heat island effect.Based on Gis and Envi platforms,this paper quantitatively analyzes the impact of various factors on urban heat islands in the context of urbanization,and proposes specific mitigation measures.This study is of great significance to improve the comfort of urban living environment,developing a good ecological urban development model,and breaking the influence of heat islands under the background of urbanization.