Research And Development Of The Geographic Information System Of The Heat Island Effect In Urumqi

With the further development of urbanization,the problem of heat island effect is becoming more and more serious.The heat island effect can reflect the city's ecological environment.It causes high temperatures inside the city,which seriously threaten the physical and mental health of the residents,and also cause the air pressure difference between urban and rural areas,exacerbating pollution within the city.Due to the western development and the "Belt and Road" initiative in recent years,Urumqi is a core city.While the economy is developing rapidly,the land-use structure has also undergone tremendous changes,which has gradually highlighted the heat island problem.Therefore,obtaining heat island effect information quickly and accurately is not only a prerequisite for mitigating the heat island effect,but also provides technical support and data support for sustainable urban development.This research was based on remote sensing(RS)and geographic information system(GIS)related theories,using ESRI's component software ArcGIS Engine,and using C#as the development language in the Microsoft Visual Studio 2012 development environment.By analyzing system requirements,the structure,framework,and functions of the system were planned,and the geodatabase was used to construct a geographic database,and then the design of the geographic temperature inversion and heat island effect geographic information system were completed.The system implemented the functions of collection,storage,management,heat island effect database,surface temperature inversion and space-time distribution analysis of heat island effect in Urumqi.The specific research content can be divided into the following five parts:(1)Selecting the Landsat 8 image of Urumqi in 2014 to verify the inversion accuracy.Obtaining the surface temperature distribution map of the two algorithms,and comparing it with the brightness temperature of the area.Through the 10-phase image,the land surface temperature(LST)of the two algorithms is obtained by inversion,and compared with the brightness temperature;(2)Comparing the supervised classification algorithms of land-use and land-cover changes(LUCC)and selecting the classification method with the best classification effect;(3)Comparing the land surface temperature retrieved by Landsat TM and Landsat OLI with the measured temperature of the weather station;(4)Studying the landscape pattern index of each year,and the relationship between the land cover and the surface temperature and heat island effect;(5)Developing the heat island effect geographic information system of Urumqi.Completing the map function module,image display module,and ground temperature change trend module.The map function module completes basic graphics processing operations.The image display module uses Landsat data from four stages of Urumqi in 1990,1998,2006,and 2014 to perform surface temperature inversion.The ground temperature change trend module can analyze the LST fluctuation range of Urumqi from 1990 to 2014 in August.The analysis and research results show that the average temperature of the image inverted by the atmospheric correction method is within 0.4? of the average value of the brightness temperature,and the average temperature of the image inverted by the single-window algorithm is within 0.1? of the average temperature of the brightness temperature.Parallel hexahedron,minimum distance,mahalanobis distance,maximum likelihood,neural network and support vector machine have an overall classification accuracy of 83.41%,82.20%,51.71%,64.03%,75.04%,93.75%.Kappa coefficients are 0.68,0.68,0.30,0.44,0.16,0.84.The error between the measured LST value in August and the surface temperature retrieved by Landsat TM and Landsat OLI is basically about 1?.And the land surface temperature can be used for the study of the spatial and temporal distribution of LST in Urumqi.The landscape pattern index varies significantly from year to year.The correlation coefficients of water,vegetation and LST of August are-0.563 and-0.439.Waters and vegetation are negatively correlated with LST,which suppresses the heat island effect and is used for construction.The apparent correlation coefficients between land,unused land and August LST are 0.392 and 0.367.Construction land and unused land are positively correlated with LST,exacerbating the heat island effect.The effect of suppressing the heat island effect can be achieved by increasing the vegetation and water area.From the perspective of spatial distribution,the heat island effect in this area is mainly concentrated in the central region,but as the year increases,the heat island area shows a radial growth trend.The ground temperature change trend module can analyze the Urumqi city from 1990 to 2014.The ground temperature change trend module can analyze the fluctuation range of LST in Urumqi from August 1990 to 2014 from 21.64? to 24.85?.