| As the development of urbanization, the Urban Heat Island(UHI) has a great influence on the human life. The strengthen UHI intensity is not only affecting temperature, but also affects the precipitation, atmospheric visibility and the distribution of atmospheric pollution staffs. So the study of UHI is helpful to the resource plantation and the protection of atmosphere. Land use and land cover changes as a major factor that influences the UHI intensity has attracts a lot attentions. The investigation of UHI, affected by LUCC, of different natural backgrounds and different development levels is significant to the future urban planning.This paper aims to research the UHI affected by the land use/land cover changes between cities which are in different natural environment and different economic level. First, typical cities are chosen based on the urbanization rate and natural environment. Second, the temperature features during the recent 20 years are researched. Then, the temporal and spatial UHI features are analyzed by using AVHRR data and MODIS data. At last high resolution land use/land cover(LUCC) data is used in Weather Research and Forecasting(WRF) by convert interface to investigate the UHI features affected by the LUCC.By combined AVHRR data and MODIS data, the temporal and spatial UHI features of typical cities are investigated. The results show that(1) The daily UHI features in Liaochen,Jinan, Qingdao and Rizhao are weaker in daytime and stronger in nighttime. However, in spring the daily UHI features of Qingdao and Rizhao are stronger in daytime and weaker in nighttime.(2)The seasonal features in the typical cities are different. While the strongest season of UHI intensity in Liaocheng and Jinan are spring and summer, the strongest seasons in Qingdao and Rizhao are spring or winter.(3)The annual changing of UHI intensity reveals the intensity of UHI are getting stronger and stronger. And the changing trend is associated with the changing of built-up areas.(4) The UHI intensities of each typical city are getting bigger is revealed by the shrink of low temperature areas and the expanding of the media temperature and high temperature areas. There are two UHI centers in Liaocheng and Jinan, while there is only on UHI center in Qingdao and Rizhao. Liaocheng and Jinan have more powerful effects on the region UHI intensity than Qingdao and Rizhao.By using the WRF model, the UHI features and the mechanism affected by LUCC are studied. The results show that(1) The combination of Lin scheme, RRTM scheme, Goddard scheme, Monin-Obukhov scheme, Noah scheme, YSU scheme, New K-F scheme and UCM scheme can best simulate the meteorological element.(2) When the WRF land use/land cover data is replaced by MOD12Q1 data, the simulation results will be improved.(3) Due to theLUCC, the UHI centers of control experiments go eastwards compared with the sensitive experiments in Liaocheng, Jinan and Rizhao. The UHI center goes westwards in Qingdao. The temperature contribution of each land use type is ordered as below:built-up>farmland>forest>unused land>grass>water body.(4) LUCC affects the UHI intensity by changing the land surface factors such as albedo, roughness, vegetation fraction and so on.Compared with the sensitive experiments, the primarily land use change is focused on the following two types: farmland transferring to built-up, farmland transferring to grass. Due to the transferring from farmland to built-up areas, the albedo and vegetation fraction decrease.The transferring from farmland to grass results in the decreasing of albedo and increasing of vegetation fraction. The exchange between land and atmosphere has changed because of the LUCC. Due to the changes, the latent heat decreases, consequently the UHI intensity increases. |
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