Analysis of Urbanization Effect on Near-Surface Wind Speed Change in Liaoning Province
Using monthly wind speed data from 1979 to 2018 in Liaoning Province and reanalysis data, combined the UMR (urban minus rural) method and OMR (observation minus reanalysis) method combined with satellite remote sensing classification methods, this paper quantitatively analyzed the impact of urbanization of Liaoning Province on near-surface wind speed. The results show that in the past 40 years, the annual and four season wind speeds in Liaoning Province have shown a decreasing trend. The decreasing rate at urban stations is significantly faster than that at rural stations. The trend of UMR value （urban-rural anomaly） is -0.11 m·s-1(10 a)-1， and the contribution rate of urbanization impact is 73.3%. In spatial distribution, the decreasing trend of urban agglomerations in central and northern Liaoning is more obvious, and the wind speed decreases relatively slowly in the south and southeast. The urbanization impact calculated by UMR method shows increasing zonal distribution from west to east. The decreasing trend at the reanalysis data is closer to that of rural stations. The decreasing rate of wind speed in spring is the most obvious. The changing trend of OMR value is -0.10 m·s-1·(10 a)-1, and the corresponding urbanization impact contribution rate is 66.7 %. The urbanization impact and contribution rate calculated by the two methods are relatively consistent, and both can reflect the impact of urbanization on wind speed to a certain extent. Reanalysis data show that the wind speed in the Bohai Strait has a slight increasing trend, and the high-value areas with reduced wind speed are located in the northern Bohai Sea and the northern Yellow Sea. In a word, the spatial distribution of the urbanization impact calculated by the two methods is that the western and southern regions are less affected by urbanization while the central and eastern regions are more affected and their consistency is better.