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Urban heat island effect and its contribution to observed temperature increase at Wuhan station, Central China

Authors:
  • China Meteorological Administration (CMA), Beijing/China University of Geosciences (CUG), Wuhan

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Based on an in-homogeneity adjusted dataset of the monthly mean temperature, minimum and maximum temperature, this paper analyzes the temporal characteristics of Urban Heat Island (UHI) intensity at Wuhan Station, and its impact on the long-term trend of surface air temperature change recorded during 1961-2015 by using an urban-rural method. Results show that UHI effect is obvious near Wuhan Station in the past 55 years, especially for minimum temperature. The strongest UHI intensity occurs in summer and the weakest in winter, on the contrary to the seasonal variation of northern cities. For the period 1961-2004, UHI intensity undergoes a significant increase near the urban station, with the increase especially large for the period 1988-2004, but a significant decrease is registered for the last 10 years, with the decrease in minimum temperature more significant than that of maximum temperature. The annual mean urban warming and its contribution to overall temperature increase are 0.18 C/10yr and 48.8% respectively for the period 1961-2015, with a more significant and larger urbanization effect seen in T min than T max. A large proportion warming, about half of the overall increase in annual mean temperature, as observed at the urban station, thus can be attributed to the rapid urbanization in the past half a century.
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... Peterson, 2003;Weng and Yang, 2004;于 淑 秋 等 , 2005;陈正洪等, 2007;Ren et al., 2007Ren et al., , 2008唐国利 等, 2008;Bian et al., 2015;丁硕毅 等, 2015;刘伟东等, 2016;Jia et al., 2019;Tysa et al., 2019),研究指出城市热岛效应在单个城市或区域 尺度上对城市气象站气温观测趋势有显著的高估作 用,且对日最低气温趋势估计的影响最为明显。 Ren et al.(2008) Bian et al., 2017;Jia et al., and Ren, 2011;杨元建等, 2011;He et al., 2013) ...
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