title: Urbanization and the thermal environment of Chinese and US-American cities.
abstract: Urbanization induced change of the thermal environment of cities is analyzed using MODIS LST and DMSP/OLS nighttime light data sets (2001-2012) to a) extend previous studies on individual megacities to a city size spectrum; b) investigate the heterogeneous surface thermal environment associated with the urbanization processes in terms of nighttime light intensity and city size; and c) provide insights in predicting how urban ecosystems will respond to urbanization for both a developing and a developed country (China and US-America), and on global scale. The following results are obtained: i) Nighttime light intensities of both countries (and globally) increase with increasing city size. ii) City size dependent annual or seasonal mean temperature tendencies show the urban effect by decreasing daytime and increasing nighttime mean temperatures (particularly in China) while variability can be related to climate fluctuations. iii) Daytime/nighttime seasonal warming tendencies (inferred from regional downscaling within city clusters) show the high light intensity regions to be stable while in low light intensity regions fluctuations prevail.
authors.affiliation: Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China. Electronic address: caidl@radi.ac.cn.
authors.forename: Danlu
authors.initials: D
authors.lastname: Cai
authors.affiliation: Max-Planck-Institute for Meteorology, Hamburg, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Fraedrich
authors.affiliation: Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China. Electronic address: guanyn@radi.ac.cn.
authors.forename: Yanning
authors.initials: Y
authors.lastname: Guan
authors.affiliation: Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Guo
authors.affiliation: Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Zhang
keywords: City size; Light intensity; MODIS daytime/nighttime temperature tendency; Surface thermal environment; Urbanization