Revealed variations of air quality in industrial development over a remote plateau of Southwest China: an application of atmospheric visibility data

Abstract

Since the 1980s, an industrial development has bloomed in China including the Yunnan–Guizhou Plateau (YGP), a remote region in Southwest China. To analyze the regional variations in air quality over YGP during the industrial development, we adopt the equivalent visibility by excluding the influence of natural factors on the observed visibility based on the meteorological data observed at 203 sites over YGP from 1980 to 2010 in this study. The YGP air quality exhibits the tremendous spatial differences in a general distribution from western good to eastern poor air quality. A similar pattern shifts seasonally in the spatial distribution with a typical seasonality of air quality over YGP between summertime low air pollution and wintertime high air pollution. The increasing and decreasing trends in visibility are mostly concentrated, respectively, in the YGP regions with high and low visibility, displaying the phenomenon of polarization in air quality change over YGP during 1980–2010. The regional mean visibility of the YGP presents a significant declining trend with change rate of −1.5 km decade−1 for air quality deterioration. The seasonal differences in visibility between summer (33.6 km) and winter (25.2 km) became obscure with the interannual change trends of visibility with stronger declines (−2.29 km decade−1) in summer and weaker decreases (−0.89 km decade−1) in winter over 1980–2010, which lead to a indistinct seasonality of air quality change over YGP. The remote YGP had experienced more frequent haze pollution, especially in the eastern plateau over 31 years. In accompany of increasing energy consumption in the industrial development, population growth is an important factor influencing the interannual change of YGP air quality. The distinct spatial distribution in the YGP terrain exerts an impact on poor air quality in lower flatlands harbored by mountainous topography with good air quality. Declined monsoon winds could meteorologically drive the air quality change with less regional transport of air pollutant over YGP during 1980–2010. Implications of the climate change for atmospheric environment will be having potential utility for sustainable development in China.