Study On Urban Heat Island Of Anhui Province Based On Ground Observation And Remote Sensing Data

With the development of the city, urban heat island effect was enhanced, research itsvariation law and formation mechanism, to the understanding of regional climate change,city development and planning and mitigation of urban heat island effect has importantsignificance.Using the data of81weather stations0f Aflllui Province，the characteristics oftemperature series were analyzed．The selected46stations were classified into urbanstations(US)，rural stations(RS)，and basic／referenee stations(BS)．The seasorlal andannual variations of mean，maximum，and minimum temperatures at the46stations wereanalyzed during1966—2005．Secondly, to make up for the Insufficient of traditionalground-based observation data in study of heat island effect, elect the representative ofAnhui city from the geographical location, climate characteristics, social and economicaspects, use the data of high spatial resolution TM and high time resolution MODIS toanalysis the distribution characteristics in space and time on the behalf of city heat islandeffect. Lastly, analysis the distribution factor of urban heat island effect through NDVI、LUCC and social driving factors. The main conclusions are summarized as follows:①1966-2005year annual average temperature increase in varying degrees, differenttypes of stations on the average, maximum, minimum temperature warming rate maximumto city station (US), basic/base station (BS) times, country station (RS) minimum, thesame type of station temperature variation is different elements: minimum temperaturewarming rate> average temperature warming rate> maximum temperature warming rate.The province’s highest temperature warming rate showed a decrease from south to Northdistribution; minimum temperature warming rate showed increasing distribution fromsouth to north.②Observation environment change of station" to" city heat island temperature has themost direct reason, satellite remote sensing display2003Hefei National Basic weatherstation of city environment are most severely affected, while the Anhui province nationalclimate base station location of urbanization affecting smaller, better protection ofobservation environment.③Hefei heat island effect did not appear in the center of the city center area, thesurface temperature has obvious southeast northwest high, low island pattern exists.Fuyang, Hefei, Wuhu three days and seasons have different degrees of heat island effect, Hefei region in recent five years UHII>3℃"extreme" heat island effect have eased. Inautumn and winter, night heat island effect is stronger than daytime; in spring and summer,the heat island effect is stronger than the night the day, most of the strong urban heat islandeffect appears in the spring, summer day. Each season has different degrees of heat islandeffect, during the spring and summer, the intensity of heat island area is large; at night, theintensity of heat island area is almost.④The transformation from non-urban land use to urban land use was the majorcharacteristic of land use change in city, and it was affected mainly by the populationincrease, rapid economic development economy, policy support, rising traffic infrastructureconstruction and many other factors. The direct effect is that the land surface temperatureincreased (decrease) with the drop (rise) of NDVI. It implied that enhance the proportionof the urban vegetation cover would play a significance role in cooling of the land surfacetemperatures in city. In water area, there was a weak cold island effect in the daytime,while a high value of heat island intensity in the nighttime. It suggested that wide waterbody is effective for reducing the urban heat island effect in the daytime. Vegetation andwater bodies in cities mainly contribute to low and sub-low temperature areas, whichlocated in the margin of the city. Especially, the cultivated land played a unique role indifferent levels of the heat island effects.