2000-2019年北京市热岛效应时空变化特征及影响因素

Study and influence factors of heat island spatio-temporal changes in Beijing from 2000 to 2019

城市热岛效应是当前城市生态系统中重要的生态环境问题,对当地气候、居民健康、经济发展等均有较大影响。选取北京市作为研究区域,基于MODIS遥感卫星数据反演地表温度,分析2000年以来热岛效应时空变化、气象条件、植被覆盖对城市气温的影响。结果表明:2000年以来,北京热岛面积呈增加趋势,平均每年增加60.2 km^2,2015年热岛面积达到最大;另外,2000年以来,北京市年平均气温和高温日数均呈升高趋势,其中城区年平均气温平均每10年增加0.5℃。北京市年平均气温增加速度从城区到远郊逐渐减少,城区气温增加速度明显大于郊区。北京市植被覆盖度与城市气温呈显著负相关,有93.0%的区域植被覆盖度呈现增加趋势,且城区植被覆盖度增加速度大于郊区。北京城区植被对气温调节的贡献仍要小于其他因子对城市气温增加的贡献,建议城市规划时还需考虑其他人为因素对城市气温的影响。研究结果可为北京市城市规划布局以及植被种植区划提供依据。

Heat island effect is now the most important ecological problem in the cities,and it has impact on local climate,resident health and economic development.Beijing is selected as the studied area in this study,based on the MODIS satellite data,analysed the heat island changes and the meteorological conditions and vegetational covers which affect the heat island.The results showed:the heat island areas were increased from 2000,the average speed was 60 km 2 each year,the most area formed in 2015.Moreover,the average temperature and high-temperature number of days were all increased from 2000,and the average temperature increased by 0.5℃in 10 years in urban.The average temperature increased speed decreased from urban to suburban,and the increased speed in urban were much higher than in suburban.The vegetation coverage had a negative correlation with temperature,and the vegetation coverage had increased by 93%of the whole area,The increased speed in urban was much higher than in suburban.The influence of vegetation to the temperature was less than other factors and suggested that anthropogenic factors should be considered in the city planning.