Constraining the uncertainty of urbanization effect on surface air temperature change over the <scp>Beijing–Tianjin–Hebei</scp> region in China

Quantitative assessment of urbanization effect on surface air temperature (SAT) change provides crucial basis for formal detection and attribution analyses climate change. However, debates about urbanization-related warming bias in documented regional SAT trend still persist, mainly due to different determination rural stations. Here the over Beijing–Tianjin–Hebei region China during 1980–2019 is estimated through three kinds ways (i.e., comparisons between urban stations [arithmetically station-averaged], urban-dominated rural-dominated patches [patch-weighted mean], realistic areas [area-weighted mean]). The last method explicitly takes land cover fractions into account when calculating urban/rural mean trends. Urbanization-induced annual (areas) are as 0.159°C, 0.195°C, 0.138°C per decade, respectively. And averaged calculated by patch-weighted area-weighted methods 0.113°C 0.050°C respectively, which 33.8% 14.8% total warming. observed considering proportions much lower than traditional station-unweighted way.