北京城市热岛环境时空变化规律研究

借助北京地区1997年、2004年的Landsat TM热红外图像,在RS和GIS技术的支持下,利用大 气探空数据对图像进行大气校正,采用单窗算法反演得到北京市区和周围地区的地表温度分 布图,地面验证表明单窗算法反演地表温度具有较高的精度.研究发现,北京市存在明显的 城市热岛效应;不同下垫面所对应的地表温度有明显差异,总体上城区地面温度明显高于郊 区,水体温度最低;随着城市规模的扩张,北京市的城市热岛效应有逐年增强的趋势,且人为因素对城市热岛的贡献逐渐加大.

Study on Temporal and Spatial Distribution Characteristics of the Urban Heat Island in Beijing

In this paper,according to atmospheric observation data,atmospheric correction was firsdy done by MODTRAN software to thermal - infrared images of Landsat - TM in 1997 and 2004 in Beijing. Then on the basis of atmospheric correction, the single- window algorithm was used to retrieve the land surface temperature (LST) of urban district and surrounding area of Beijing with the help of RS and GIS technology. The ground measurements show that there is the higher accuracy of single-window algorithm to LST retrieval. The results also show that there is the clear urban heat island(UHI) in Beijing, there is the obvious difference among the different land surface cover type,the LST of urban center is higher than that of suburb area,the temperature of water is the lowest. In addition, there is the clear intensification trend of UHI and the factitious impacts produce the more contribution to UHI in Beijing with the quick expansion of urban area and urban population.