Abstract. 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 (PM2.5) 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 (SO2), nitrogen oxides (NOx), PM2.5,
inhalable particles (PM10), carbon monoxide (CO), ammonia (NH3),
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 −48 %
for SO2, −0.5 % for NOx, −16 % for PM2.5, −22 % for
PM10, 13 % for CO, 3 % for NH3, and 13 % for VOCs. The
declines of SO2, NOx, PM2.5, and PM10 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 (SO2 and NOx), industrial
combustion (SO2, PM2.5, PM10), on-road mobile sources
(NOx), and dust sources (PM2.5 and PM10). 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 SO2 and NOx 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 SO2 emissions in GD, for example, increased from
27 % in 2006 to 48 % 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.
