| Urbanization development obviously impact climate factors, and appear urban five islands effectsand a series of impacts for people's production and living. At present, it has important meaning toresearch the applied field of urban climate at the aspects of environment construction, urban standard,urban architectural design, urban energy sources using and people's living health. In the recent fiftyyears, urbanization of Lanzhou shows a quick increasing period, integrated effect including artificialand original influence factors bring prominent and particular urban climate effect compared to the othercity. So, it is necessary to research on the temporal-spatial characteristics and formation mechanisms ofurban climate effect in Lanzhou. The following is the research work.1. Observation experiment of Bowen ratio system has been on at Lanzhou University located atcircle road and Yuzhong for about one year, the observation data and meteorological data including tenweather stations are used. Urban climate factor characters, air temperature and humidity character inthe surface boundary layer are researched, and urban five islands effect and their daily, seasonal andannual variation characters are analyzed. The results show that urban climate effect of Lanzhou is moreprominent than the others' city. In the recent fifty years, urban heat island intensity is 0.21℃/10a, thecontributing rate of urban heat island effect to temperature reaches 56.8% which is higher than thenational average level, the rate and range of increasing temperature are twice as many as the nationalaverage level. Urban dry island is obvious distinct in spring, summer, autumn and winter, and it is themost prominent in summer and is the weakest in winter. Urban moisture island is not distinct. Urbanrain island does not exist.2. Based on GIS spatial interpolation methods and TM6 remote sensing data from Qin ZhihaoMono-window algorithm and Jimenez-Munoz & Sorbrino single-channel algorithm, spatial distributionand profile character of Lanzhou temperature and humidity fields in earth's surface are obtained. Theresults show that high temperature field appears the commerce section and uptown with high densitypopulation and high building volume and industrial estate with high energy consume and strong heatfountainhead, low temperature field appears the around section with high vegetation cover and lowbuilding volume. Spatial distribution of humidity field is not distinct, high humidity field is related tothe vegetation cover. Difference of greenbelt, water, building volume, population density, energyconsume, underlying surface character and urban function area bring large difference of temperatureand humidity field interior structure.3. Urban heat island is simulated by using the model of build heat system and urban climatecoupling. Distributing character of energy flux and temporal-spatial distribution of different climatefactors at urban cover layer for research of the middle scale of climate effect are obtained. Therelationship between urban heat island and build factor, society economic index are analyzed, theresults show climate effect has close relation to population, urban scale, underlying surface and atmosphere condition.4. The trend of different climate factors based on R/S method is forecasted, and memory length oftime sequence is analyzed. It shows time sequence of different climate factors exist clear fractalstructure, annual average temperature and four seasons temperature show a climbing trend with acharacter of durative. Annual average and four seasons relative humidity show a fluctuant degressivetrend with further strong durative. In the future, precipitation is durative degression in spring and winter,precipitation is still durative weak increase in summer, annual average precipitation and autumn'sprecipitation show inverse durative character with a trend of increase in the future.
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