Research On The Mapping Of Urban Climate Map Based On LCZ Model And WRF Simulation

In recent years,there is a rapid development of constructions in China.These high-intensity constructions have changed the form of underlying surface of cities,influencing the physical and morphological characteristics of land surface.Besides,high-intensity constructions also influenced the climate,wind,humidity and other climatic factors of cities,affecting the health of urban residents and impeding sustainable development.For instance,it would result in frequent heat waves in summer and severe air pollution in winter.Thus,it is necessary to use urban climate information into urban planning and design.Urban climate map is taken as a tool for assessment and analysis of urban climate and environmental information.It can be used for linking urban climate with urban morphology.It can also visualize urban climate phenomena and climate problems.By using urban climate map,it is convenient for designers to consider the urban form elements and urban climate elements into the process of urban planning and design.Urban climate map can also play an essential role in the guidance and application of urban environmental information into urban planning and design.Urban climate map has been widely applied in the research of urban climate problems.However,the traditional method of mapping urban climate map still existed a problem of insufficient description of the climate situation.This is because that it is difficult to obtain basic climate data at urban scale.Meanwhile,in traditional method,urban climate map was obtained by overlying urban morphology and geomorphologic layers,rather than directly using basic climate data to analyze the urban climate status.It means that the influences of different urban morphologies were ignored due to indirect description of urban climate status in traditional method.This is also the key issue in the mapping of urban climate map in this study.For addressing the shortcoming of existing methods for obtaining urban climate map,a new mapping method of urban climate map was proposed in this study,which was based on LCZ model and WRF simulation.Next,a complete urban climate map compilation framework was developed.Firstly,in order to solve the problem of inaccurate underlying surface data of WRF(Weather Research and Forecasting model),the urban morphological data collected based on Local Climate Zones(LCZ)and topographic data were used to modify the underlying surface model of WRF.And validations of the results of WRF simulation against the tested values were conducted to confirm the accuracy of basic climate data.It can be observed that the using LCZ to modify the WRF underlying surface can improve the accuracy of the simulation obviously.Secondly,based on the real urban underlying surface boundary conditions and climate boundary conditions,WRF forward simulation was performed to obtain the basic climate data,and the relevant climate evaluation indicators are used to quantify the basic climate data for mapping the urban climate map.The comprehensive physical process program of WRF could ensure that the complex phenomena of urban climate in geographic space and the mutual influence of urban grids were fully considered in the process of numerical simulation.A better assessment and analysis of the urban climate can be obtained by using the results of WRF simulation.Based on the data obtained above,Nanjing was used as an example to study the practical application of the proposed mapping method.Nanjing is located in the area with hot summer and cold winter,the climate comfort in both seasons is low.Thus,the urban climate status in both seasons in Nanjing was analyzed and evaluated.After comprehensive consideration of Nanjing climate status in summer and winter,corresponding planning suggestions and control strategies were proposed for the purpose of urban climate control.The whole thesis contains about 53503 words,119 pictures and charts.