Impacts of Wind Farms on Land Surface Temperature ——A Case Study on the Wind Farm in Northern Zhangjiakou， Hebei

Abstract

Extensive use of wind energy resources in China not only brings huge economic benefits， but also reduces environmental pollution caused by various fossil fuels.However， some studies have shown that the rotation of the rotor blades will increase surface roughness and then enhance turbulence in the rotor wakes by changing the stability of the atmospheric boundary layer （ABL）.If these changes are spatially large enough， they may affect the local and even regional weather and climate.With increasing installed capacity of wind farms， a correct understanding of the possible impacts of wind power on climate is needed， especially its impact on temperature.It is of great significance for the scientific use of wind energy resources and ensuring the sustainable development of energy in China.Satellite remote sensing technology can conduct large-scale， long-term， and regular observations of the land surface， and data acquisition is relatively easy.The MODIS satellite data has been used in studies of the impact of wind farms on the land surface temperature.Based on MODIS satellite data from 2003 to 2019， this paper explores the impact of two large wind farms in Shangyi and Zhangbei in northern Zhangjiakou on land surface temperature.Combined with wind direction， vegetation index， surface albedo， and land use data， the results show that： （1）During spring， autumn， and winter， the land surface temperature downwind of the wind farm is higher than that upwind during nighttime， the opposite is true during the day.The land surface temperature in the downwind area of the wind farm is significantly affected by the wind turbine wake.（2）Compared with the surrounding areas not affected by wind farms， the land surface temperature within wind farms increased significantly in spring and summer， especially during spring night with an increaing trend of 0.379 ℃·（10a）-1， followed by summer night and autumn night with increaing trends of 0.206 ℃·（10a）-1 and 0.211 ℃·（10a）-1， respectively.The warming trends` spatial pattern couples well with the geographic distribution of wind turbines.（3）Although wind farms in Shangyi and Zhangbei have impacts on LST， compared with other studies the increasing trends caused by wind farms in this study area is weak and much smaller than the interannual LST increasing trend in the Bashang area with increaing trends of 0.817 ℃·（10a）-1， the land surface temperature increases caused by the operation of wind turbines is negligible compared with which caused by fossil fuels.Changes in land surface temperature within wind farms are not only affected by the operation of wind farms but also a combination of various influencing factors， such as climate change， vegetation， and land-use changes.

Keywords

• wind power
• wind farm
• atmospheric boundary layer （abl）
• land surface temperature