Evolution of anthropogenic air pollutant emissions in Guangdong Province, China, from 2006 to 2015

• Main Authors: Y. Bian, Z. Huang, J. Ou, Z. Zhong, Y. Xu, Z. Zhang, X. Xiao, X. Ye, Y. Wu, X. Yin, C. Li, L. Chen, M. Shao, J. Zheng
• Format: Article
• Language: English
• Published: Copernicus Publications 2019-09-01
• Series: Atmospheric Chemistry and Physics
• Online Access: https://www.atmos-chem-phys.net/19/11701/2019/acp-19-11701-2019.pdf
• ISSN: 1680-7316; 1680-7324

<p>Guangdong Province (GD), one of the most prosperous and populous regions in China, still experiences haze events and growing ozone pollution in spite of the substantial air-quality improvement in recent years. Integrated control of fine particulate matter (PM<span class="inline-formula">_2.5</span>) and ozone in GD calls for a systematic review of historical emissions. In this study, emission trends, spatial variations, source-contribution variations, and reduction potentials of sulfur dioxide (<span class="inline-formula">SO₂</span>), nitrogen oxides (<span class="inline-formula">NO_<i>x</i></span>), PM<span class="inline-formula">_2.5</span>, inhalable particles (PM<span class="inline-formula">₁₀</span>), carbon monoxide (CO), ammonia (<span class="inline-formula">NH₃</span>), and volatile organic compounds (VOCs) in GD from 2006 to 2015 were first examined using a dynamic methodology, taking into account economic development, technology penetration, and emission controls. The relative change rates of anthropogenic emissions in GD during 2006–2015 are <span class="inline-formula">−48</span>&thinsp;% for <span class="inline-formula">SO₂</span>, <span class="inline-formula">−0.5</span>&thinsp;% for <span class="inline-formula">NO_<i>x</i></span>, <span class="inline-formula">−16</span>&thinsp;% for PM<span class="inline-formula">_2.5</span>, <span class="inline-formula">−22</span>&thinsp;% for PM<span class="inline-formula">₁₀</span>, 13&thinsp;% for CO, 3&thinsp;% for <span class="inline-formula">NH₃</span>, and 13&thinsp;% for VOCs. The declines of <span class="inline-formula">SO₂</span>, <span class="inline-formula">NO_<i>x</i></span>, PM<span class="inline-formula">_2.5</span>, and PM<span class="inline-formula">₁₀</span> emissions in the whole province mainly resulted from the stringent emission control in the Pearl River delta (PRD) region, where most previous control measures were focused, especially on power plants (<span class="inline-formula">SO₂</span> and <span class="inline-formula">NO_<i>x</i></span>), industrial combustion (<span class="inline-formula">SO₂</span>, PM<span class="inline-formula">_2.5</span>, PM<span class="inline-formula">₁₀</span>), on-road mobile sources (<span class="inline-formula">NO_<i>x</i></span>), and dust sources (PM<span class="inline-formula">_2.5</span> and PM<span class="inline-formula">₁₀</span>). Emissions from other areas (non-PRD, NPRD), nevertheless, remain relatively stable due to the lax control measures and rapidly growing energy consumption. In addition, emission leaks of <span class="inline-formula">SO₂</span> and <span class="inline-formula">NO_<i>x</i></span> from industries are observed from PRD to NPRD in 2010 and 2011. As a result, emissions in NPRD are increasingly important in GD, particularly those from industrial combustion. The contribution of NPRD to the total <span class="inline-formula">SO₂</span> emissions in GD, for example, increased from 27&thinsp;% in 2006 to 48&thinsp;% in 2015. On-road mobile sources and solvent use are the two key sources that should receive more effective control measures in GD. Current control-driven emission reductions from on-road mobile sources are neutralized by the substantial growth of the vehicle population, while VOC emissions in GD steadily increase due to the growth of solvent use and the absence of effective control measures. Besides, future work could focus on power plants and industrial combustion in GD and industrial process sources in NPRD, which still have large emission reduction potentials. The historical emission inventory developed in this study not only helps to understand the emission evolution in GD, but also provides robust data to quantify the impact of emission and meteorology variations on air quality and unveil the primary cause of significant air-quality change in GD in the recent decade.</p>