This document outlines a presentation on secondary inorganic aerosol in the Yangtze River Delta region of China. It begins with an introduction to secondary inorganic aerosol and objectives of the study. It then describes the results of two measurement campaigns - one in Shanghai and one in Hangzhou. The document analyzes meteorological conditions, chemical composition of particulate matter, and relationships between different components. It finds that secondary inorganic species like nitrate and sulfate compose a significant fraction of fine particulate matter and their levels do not significantly vary between clear, hazy and foggy weather periods. The presentation aims to improve understanding of secondary inorganic aerosol behavior and role in the Yangtze River Delta region.
Criteria Air Pollutants and Ambient Air Monitoring
Fudannonmov
1. Secondary Inorganic Aerosol in the Yangtze River Delta of China
Roeland Cornelis JANSEN
12110740001
PhD defense presentation
Fudan University Handan Road 220, 200433, Shanghai China
November 30, 2014
Professor Jianmin CHEN
2. Outline:
1. Introduction:
• Introduction in Secondary Inorganic Aerosol and the Yangtze River Delta of China and objectives of this study
2. Experimental part:
• Results from 2 campaigns: Shanghai and Hangzhou
3. Conclusions and suggestions for further work
4. Acknowledgment
5. Q&A
3. Introduction: The Yangtze River Delta of China
Millions of people
Millions of cars
Thousands of factories
Tons of emission
A lot of agriculture
…
NOx SO2 NH3
4. Tropospheric NO2 concentrations in east China mapped with the
ERS-2 research satellite during the Global Ozone Monitoring
Experiment (GOME). Reprinted from Huang et al., 2011.
Introduction: Emissions in Yangtze River Delta of China
Point sources in the Yangtze River Delta: left
power plants and right: industrial point sources
Reprinted from Li et al.,2011
5. Reprinted from Aneja et al., 2001
Formation, growth and removal of atmospheric aerosol
6. Samples are all sub-micrometer aerosol. Reprinted from
Jimenez et al., 2009.
Introduction: Secondary Inorganic Aerosol (SIA)
Precursor gasses NH3, SO2 , NOx and HCl react
(SO2 and NOx after oxidation) to form SIA:
2 NH3(g) + H2SO4(l) (NH4)2SO4(l)
NH3(g) + HNO3(g) NH4NO3(s or l)
NH3(g) + HCl(g) NH4Cl(s or l)
SIA makes up 30-70% of the total mass of
submicron aerosol (PM1)
7. Reprinted from Malm, 1999
Studies on SIA role and behavior
Hygroscopic properties
Reprinted from Tang, 1979
Scattering of radiation
Effects of hygroscopicity:
• Increase in water content
• Increase of particle size
• More effective scattering
• Cloud formation
Effects of scattering:
• Decrease of visibility
• Global cooling effect
Reprinted from Malm, 1999.
15. Experimental part: Correlations Visibility versus PM1 mass
Correlation of visibility vs. PM1 mass.
Correlations of visibility vs. PM1 mass for different
RH values
Conclusion: The correlation between visibility and mass concentration of PM1 depends strongly
on the relative humidity
17. Experimental part: Rel. mass contribution of SIA to PM
Shanghai PM1; December 2012; N=660
SO4
2- NO3
-
Sun et al., 2013; PM1 in Beijing
18. Classifying periods of air pollution
Visibility > 10 km.
Du et al., 2011; Xiao et al., 2011; Wu et al., 2005
Clear FogHaze
Visibility < 10 km.
RH < 90%
Time > 4 hr.
Visibility < 10 km.
RH > 90%
Time > 4 hr.
20. Experimental part: Meteorological conditions
Clear Haze Fog
Number of hours 354 114 48
T (°C) 20.9±6.1 20.8±3.8 18.4±3.2
RH (%) 61.3±16.9 73.9±11.4 93.1±1.9
Pressure (hPa) 1005±5.6 1002.7±3.6 1001.7±4.7
Wind Speed (m/s) 1.4±0.8 1.3±0.7 0.8±0.5
Visibility (km) 21.2±10.4 6.6±2.0 3.3±0.8
PM2.5 (μg/m3) 67±38 118±41 105±27
Clear Haze Fog
Number of hours 483 94 40
T (°C) 5.9±3.9 7.0±3.9 7.4±1.5
RH (%) 58.9±14.7 69.8±15.1 93.6±3.3
Pressure (hPa) 1024±3.7 1022±4.5 1019±1.7
Wind Speed (m/s) 2.4±1.1 2.6±1.1 2.2±0.9
Visibility (km) 25.6±11.2 7.2±1.9 5.4±2.1
PM1 (μg/m3) 31±17 62±26 24±9
Shanghai PM1; December 2012, n=617Hangzhou PM2.5; April-May 2012, n=516
69
22
9
clear
haze
fog
78
15
7
clear
haze
fog
%
% %%%
%
Conclusion: The visibility during fog is lowest while the mass concentration on PM is not, this
shows the importance of the RH value on visibility
21. 246231
67
118 105
Experimental part: SIA mass contribution to PM
Shanghai
PM1
Hangzhou
PM2.5
Conclusion: The SIA in aerosol changes slightly between clear, haze and fog
with nitrate being the most obvious change.
Clear Haze Fog
22. Experimental part: Molar equivalent ratio SIA
Equi-molar balance: ([NH4
+]/18) / ((2[SO4
2-]/96) + ([NO3
-]/62))2 NH3 + H2SO4 (NH4)2SO4
NH3 + HNO3 NH4NO3
Conclusion: PM1 particles in Shanghai (in Dec. ‘12) are slightly alkaline. In the balance there is
no significant difference between clear, haze and fog weather periods.
23. Experimental part: Molar equivalent SIA with Cl-
NH4
+ / (NO3
- + 2SO4
2- ) NH4
+ / (NO3
- + 2SO4
2- + Cl- )
All data (N=660) Y = 1.12x – 0.18; R2 = 0.97 Y = 0.99x – 0.42; R2 = 0.99
Clear weather (N=425) Y = 1.08x – 0.08; R2 = 0.95 Y = 0.98x – 0.42; R2 = 0.99
Haze weather (N=90) Y = 1.18x – 0.54; R2 = 0.95 Y = 1.03x – 0.74; R2 = 0.99
Fog weather (N=30) Y = 1.13x – 0.14; R2 = 0.96 Y = 0.89x – 0.14; R2 = 0.97
Y = actual measured NH4
+ concentration in μg/m3
X = predicted NH4
+ concentration in μg/m3 (sum of NO3
- and SO4
2- and NO3
- SO4
2- and Cl-)
What binds to NH4
+ at high RH values?? Lack of HSO4
- data.
Sun et al., 2013; PM1 in Beijing
24. Nitrate to sulfate molar ratio
[NO3
-]/[SO4
2-] as function of
ammonium to sulfate ratio
[NH4
+]/[SO4
2-].
Relation between molar
concentrations of [NO3
-] and
[NH4
+] – [SO4
2-].
Hangzhou PM2.5 Shanghai PM 1
Experimental part: Molar ratios of SIA
Reprinted from Pathak et al., 2009 (PM2.5)
Conclusion: Nitrate formation starts after sulfate formation and there is no significant
difference between clear, haze and fog weather periods.
Conclusion: Nitrate formation happens mainly by SIA formation
Beside sulfate and nitrate, ammonium is bound to species like chloride and bisulfate
25. Experimental part: NOAA HYSPLIT 4
500 and 1000 meter were used,
which represent the average
mixed layer height in Shanghai
(Huang et al., 2012a; Yang et al.,
2006; Kong et al., 2014).
NH3 emission sources are
Yangzhou (NW of Shanghai),
Nantong (NNW of Shanghai) and
Jiaxing (SW of Shanghai)
Huang et al., 2011.
26. 2 SCI publications in 2014
Jansen et al., 2014. Advances in Atmospheric
Sciences Nov. 2014, Vol. 31, Issue 6, pp 1427-1434
IF: 1.459
Roeland Cornelis Jansen, Jianmin Chen, and
Yunjie Hu. Advances in Meteorology, Vol. 2014,
Article ID 534675. IF: 1.348