Supplement

Chemistry-triggered events of PM2.5 explosive growth during late

autumn and winter in Shanghai, China

Wenwen Suna, Dongfang Wangb, Lan Yaoa, Hongbo Fua, Qingyan Fub, Hongli Wangc, Qing Lia,

Lin Wanga, Xin Yanga, Aiyong Xiand, Gehui Wange, Hang Xiaof, Jianmin Chena, e, f ,*

a Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of

Environmental Science & Engineering, Institute of Atmospheric Sciences, Fudan University,

Shanghai 200438, China

b Shanghai Environmental Monitoring Center, Shanghai 200235, China

c Shanghai Academy of Environmental Sciences, Shanghai 200233, China

d Yellow River Shandong Bureau, Jinan 250000, China

e Institute of Eco-Chongming, 3663 Zhongshan Road, Shanghai 200062, China

f Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment,

Chinese Academy of Sciences, Xiamen 361021, China

*Corresponding author (e-mail: jmchen@fudan.edu.cn)

Contents of the file

Number of Pages: 10

Number of figures: 8

Number of tables: 1

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

Figure S1. Location of Shanghai in China (left) and the sampling site in Shanghai (right). Note

that red star denoted Dianshanhu supersite in right picture.

Shanghai

22

23

24

25

Figure S2. (a)-(d) denote PSCF map of PM2.5 in Shanghai during late autumn and winter from

2014–2017, respectively.

26

27

28

29

Figure S3. Meteorological conditions (RH and T), PM2.5, gaseous pollutants (SO2, NO2, O3, and

CO), chemical PM2.5 components during a 3 h EG episode under stagnant conditions in Shanghai

in late autumn and winter from 2014 to 2017. Note that Ep1 occurred at 17:00–19:00 LST on

January 3, 2014; Ep2 occurred at 9:00–13:00 LST on February 2, 2014; Ep3 occurred at 8:00–

12:00 LST on January 4, 2015.

30

3132

33

34

35

36

3738

Figure S4. Apparent growth and chemical transformation of chemical components during a 3 h

EG episode under stagnant conditions in Shanghai in late autumn and winter from 2014 to 2017.

(a) EG rate of chemical PM2.5 components at 1 h, PM2.5 and chemical PM2.5 components at 3 h; (b)

CO-scaled EG rate of chemical PM2.5 components, SOR and NOR; (c) EG rate of K+; and (d) CO-

scaled EG rate of K+.

3940

41

42

43

44

4546

Figure S5. Meteorological conditions (RH and T), PM2.5, gaseous pollutants (SO2, NO2, O3, and

CO) and chemical PM2.5 components during a 9 h EG episode under stagnant conditions in

Shanghai in late autumn and winter from 2014 to 2017. Note that Ep1 occurred at 15:00 LST on

January 1 to 01:00 LST on January 2, 2014; Ep2 occurred at 16:00 LST on January 17 to 00:00

LST on January 18, 2014; Ep3 occurred at 06:00–15:00 LST on December 15, 2014; Ep4 occurred

at 14:00–23:00 LST on December 29, 2014; Ep5 occurred at 1:00–9:00 LST on January 2, 2015;

Ep6 occurred at 1:00–8:00 LST on January 8, 2015; Ep7 occurred at 1:00–9:00 LST on January

10, 2015; Ep8 occurred at 1:00–14:00 LST on December 21, 2015; Ep9 occurred at 16:00 LST on

January 17 to 1:00 LST on January 18, 2016; Ep10 occurred at 23:00 LST on February 7 to 8:00

LST on February 8, 2016; Ep11 occurred at 7:00–15:00 LST on February 1, 2017; Ep12 occurred

at 1:00–9:00 LST on December 4, 2017; Ep13 occurred at 5:00–13:00 LST on December 31,

47

48

49

50

51

52

53

54

55

56

57

58

2017.

Figure S6. Apparent growth and chemical transformation of chemical components during an EG

episode at 9 h under stagnant conditions in Shanghai in late autumn and winter from 2014–2017.

(a) EG rate of chemical PM2.5 components at 1 h, PM2.5 and chemical PM2.5 components at 9 h; (b)

CO-scaled EG rate of chemical PM2.5 components, SOR and NOR; (c) EG rate of K+; and (d) CO-

scaled EG rate of K+.

59

60

6162

63

64

65

66

Figure S7. Trend of NH4+ equivalent concentration as a function of (NO3

- + SO42-) equivalent

concentration with RH during Ep5 at 6 h.

6768

69

70

Figure S8. (a)Trend of NH4+ equivalent concentration as a function of (NO3

- + SO42-) equivalent

concentration with RH at 6 h; (b)Trend of the molar ratio of NO3- to SO4

2- and NH4+ to SO4

2- with

RH; (c)The change trend of molar concentration NO3- with excess NH4

+ at 6 h.

71

7273

74

75

76

Table S1 EG rates of SNA, OC and EC at 3, 6 and 9 h under stagnation respectively for Shanghai

in late autumn and winter from 2014–2017.

NO3- SO4

2- NH4+ OC EC

2014

3 h 6.7 3.8 5.4 - -

6 h 3.2 4.1 3.2 1.6 0.4

9 h 1.8 1.4 1.8 - -

2015

3 h 5.8 2.7 4.4 - -

6 h 1.8 1.6 2.0 1.3 0.5

9 h 1.3 1.6 1.9 1.0 0.4

2016

3 h - - - - -

6 h 3.3 2.0 2.8 1.5 0.6

9 h 1.3 1.4 1.1 0.9 0.7

2017

3 h - - - - -

6 h - - - - -

9 h 5.4 2.5 1.9 0.6 0.2

77

78

79

80