Long‐Term Trends of Anthropogenic SO₂, NO_x, CO, and NMVOCs Emissions in China

Abstract

Studies reporting the historical trends of SO 2 , NO x , CO, and nonmethane volatile organic compounds emissions in China using unified approaches and sources are limited. Here we established 66-year emission trends of these four species in China. Six primary anthropogenic sources were included, and we made a series of improvements to the few existing inventories based on detailed statistical data, recently published emission factors, and technology renewal to reduce the uncertainties. National SO 2 , NO x , CO, and nonmethane volatile organic compounds emissions in 2015 were 27.1, 20.6, 188, and 28.4 Mt, with annual growth rates of 5.8%, 5.9%, 3.8%, and 4.6% since 1949, respectively. In recent years, fossil fuel combustion was the major contributor to SO 2 , NO x , and CO emissions, whereas industrial process contributed most to VOCs emissions. Our results revealed a 10% decrease in the SO 2 emissions from 2005 to 2010 as a result of improvements in the flue gas desulfurization installation rate. NO x emissions stopped rising and started falling in 2011, with technology renewal and the penetration of end-of-pipe control measures in industrial boilers and cement production. Furthermore, we calculated future speciated VOCs emissions and ozone formation potential under alternative policy scenarios and projected to reduce emissions by 10% (compared with 2013 levels) with stringent control measures in 2020. A reactivity-based control strategy was proposed to achieve greater ozone formation potential reductions while requiring less VOCs emissions reduction. Plain Language SummaryOver past half century, the emissions of air pollutants generated through human activities in China have increased rapidly. The study of long-term emissions trends will improve our understanding of human influence on climate change and air quality. Here we established 66-year emission trends of four major species for the first time and evaluated the impact of government policy on emission. The central government initialed the most stringent ever action plan in China to cut emissions, for example, from 1 January 2018, China began to levy environmental protection tax, aimed at SO 2 , NO x , CO, VOCs, and other pollutants. Our result reveals a decrease in the SO 2 and NO x emissions, consistent with satellite observation, while VOCs emissions continued to rise. The emission-based reduction plan for VOCs have been implemented nationwide. In this study, we further proposed a reactivity-based control strategy to improve the air quality more effectively.SUN ET AL.

Effect of changing NO<sub><i>x</i></sub> lifetime on the seasonality and long-term trends of satellite-observed tropospheric NO<sub>2</sub> columns over China

“…γ NO 3 is taken to be 1 × 10 −3 following Jacob (2000). γ NO 2 for the hydrolysis Reaction (R11) is de- creased from 1 × 10 −4 (Jacob, 2000) to 1 × 10 −5 on the basis of laboratory measurements (Bröske et al, 2003;Stemmler et al, 2007;Tan et al, 2016). This decrease in γ NO 2 yields a 24 h mean wintertime HONO/NO 2 molar concentration ratio of 0.035 over eastern China in GEOS-Chem, consistent with the observed range of 0.015-0.071 (Hendrick et al, 2014;Spataro et al, 2013;Wang et al, 2017Wang et al, , 2013.…”

Effect of changing NO<sub><i>x</i></sub> lifetime on the seasonality and long-term trends of satellite-observed tropospheric NO<sub>2</sub> columns over China

“…These observations have been qualitatively consistent with the 35 trends in Chinese NOx emission inventories, showing an increasing trend of NO2 columns over China between 1994 and and a sharp reversal in eastern China since 2011 (Richter et al, 2005;van der A et al, 2006, 2008Krotkov et al, 2016;Schneider et al, 2015;Duncan et al, 2016;Cui et al, 2016). However, the trends in the NO2 columns are steeper than in the emission inventories (Zhang et al, 2007;Stavrakou et al, 2008;Zhang et al, 2012b;Hilboll et al, 2013;Liu et al, 2017;Zheng et al, 2018). For example, Zhang et al (2007) found that NO2 columns over China increased two-fold from 1996 40 to 2004 while their emission inventory reported a 60% increase.…”

“…Since then, China has adopted strong measures to decrease air pollution by setting stringent emissions standards, capping coal use, increasing vehicle fuel efficiency, closing outdated facilities, and growing renewable energy 30 Zheng et al, 2018). Bottom-up inventories estimate that China's NOx emissions decreased by 20% between 2011 and 2017, despite continuing economic expansion Zheng et al, 2018). There is a strong need to evaluate these emission inventories and their trends for air quality management.…”

The Role of Anthropogenic Aerosol Forcing in Interdecadal Variations of Summertime Upper‐Tropospheric Temperature Over East Asia

“…In fact, the scenario discussed above may have already happened. Recent studies have indicated that SO 2 emissions in China have decreased since 2005 (Li et al, ; Sun et al, ), which significantly contributed to the decline in global SO 2 emissions (Klimont et al, ). Furthermore, Zhao et al () found that the JA mean UTT in East Asia exhibited a significant increasing trend and that the EASM circulation was intensified at the beginning of the 21st century using the NCEP‐NCAR reanalysis data set from 1951 to 2013.…”