Do More Frequent Temperature Inversions Aggravate Haze Pollution in China?
Kaixu Bai, Ke Li, Jianping Guo, Wei Cheng, Xiaofeng Xu
Abstract
Abstract By using twice daily high‐resolution radiosonde observations, here we assessed spatiotemporal variability of temperature inversion (TI) and its impact on PM 2.5 pollution levels in China from 2014 to 2020. It was found that both surface‐based inversion (SBI) and elevated inversion (EI) became increasingly frequent across China, at a rate of 1.42% a −1 (1.15% a −1 ) and 2.82% a −1 (3.23% a −1 ) at 0800 (2000) Beijing time (BJT), respectively. However, the intensity of SBI and EI at 0800 (2000) BJT decreased at −0.17 (−0.43) and −0.07 (−0.05) °C 100m −1 decade −1 , making annual mean PM 2.5 increment induced by TI dip by 52.5% (73.2%) for the whole study period. Still positive TI induced PM 2.5 increments demonstrate an offsetting effect between TI and emission control on haze pollution, underscoring the importance of fully considering TI contribution when assessing the emission control effect on haze reduction.