Articles | Volume 17, issue 3
Atmos. Chem. Phys., 17, 1775–1789, 2017

Special issue: East Asia emissions assessment (EA2)

Atmos. Chem. Phys., 17, 1775–1789, 2017

Research article 06 Feb 2017

Research article | 06 Feb 2017

Cleaning up the air: effectiveness of air quality policy for SO2 and NOx emissions in China

Ronald J. van der A1,2, Bas Mijling1, Jieying Ding1,3, Maria Elissavet Koukouli4, Fei Liu1, Qing Li5, Huiqin Mao5, and Nicolas Theys6 Ronald J. van der A et al.
  • 1Royal Netherlands Meteorological Institute (KNMI), De Bilt, the Netherlands
  • 2Nanjing University of Information Science and Technology, Nanjing, P.R. China
  • 3Delft University of Technology, Delft, the Netherlands
  • 4Laboratory of Atmospheric Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
  • 5Satellite Environment Center, Ministry of Environmental Protection, Beijing, P.R. China
  • 6Belgian Institute for Space Aeronomy (BIRA-IASB), Brussels, Belgium

Abstract. Air quality observations by satellite instruments are global and have a regular temporal resolution, which makes them very useful in studying long-term trends in atmospheric species. To monitor air quality trends in China for the period 2005–2015, we derive SO2 columns and NOx emissions on a provincial level with improved accuracy. To put these trends into perspective they are compared with public data on energy consumption and the environmental policies of China. We distinguish the effect of air quality regulations from economic growth by comparing them relatively to fossil fuel consumption. Pollutant levels, per unit of fossil fuel, are used to assess the effectiveness of air quality regulations. We note that the desulfurization regulations enforced in 2005–2006 only had a significant effect in the years 2008–2009, when a much stricter control of the actual use of the installations began. For national NOx emissions a distinct decreasing trend is only visible from 2012 onwards, but the emission peak year differs from province to province. Unlike SO2, emissions of NOx are highly related to traffic. Furthermore, regulations for NOx emissions are partly decided on a provincial level. The last 3 years show a reduction both in SO2 and NOx emissions per fossil fuel unit, since the authorities have implemented several new environmental regulations. Despite an increasing fossil fuel consumption and a growing transport sector, the effects of air quality policy in China are clearly visible. Without the air quality regulations the concentration of SO2 would be about 2.5 times higher and the NO2 concentrations would be at least 25 % higher than they are today in China.

Short summary
The SO2 concentrations and NOx emissions over China derived from satellite observations are compared with the national fossil fuel consumption and air quality regulations. It is shown that not only NO2 concentrations but also NOx emissions in all Chinese provinces decreased in the last 2 years. We conclude that without the air quality regulations the SO2 concentrations would be about 2.5 times higher and the NO2 concentrations would be at least 25 % higher than they are today in China.
Final-revised paper