Air pollution in northern and southern China: overview of the measurements at two mountain-top sites T. Wang1, 2; L. Xue3, 1; X. Gao3; W. Nie3, 1; X. Wang3; Y. Wang4; M. Sun4; A. Ding1; S. Fan5; Q. Zhang3; W. Wang3, 2 1.Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China 2.Chinese Research Academy of Environmental Sciences, Beijing, China 3.Environment Research Institute, Shandong University, Ji’nan, Shandong, China 4.School of Environmental Science and Engineering, Shandong University, Ji’nan, Shandong, China 5.School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, Guangdong, China

Outline • Why chose the two mountains • Some results (ozone, PM, cloud)

As a part of the National Basic Research Program on Acid Rain Pollution in China (2005-2010)

Aircraft, 2007 Beijing, 2008 Mt. Tai, 2007

Mt. Heng, 2009

http://www.cgrer.uiowa.edu/EMISSION_DATA_new/index_16.html.

Why Mt Tai? •

The highest point in CEChina

•

Strong emissions

•

Suitable to study cloudpollution interaction

Measurements at Mt Tai (1534 m a.s.l.) Periods ：spring phase: 2007.3.17 -4.24 Periods：spring 2007.3.17-4.24 2007.6.14-7.22 summer phase: 2007.6.14-7.22 Species:


Precursors and trace gases SO2, NOx, NH3, NOy, PAN, CO, VOCs




Oxidants O3, Total peroxides




Aerosols PM2.5, PM10, BC, IC, EC/OC, WPS, Filter sampling




Precipitation pH, ions, organic acids, H2O2




Cloud/Fog pH, ions, organic acids, H2O2, HCHO, S(IV)

Why Mt. Heng? • Within the region of the most acidic rain in southern China • Frequent clouds/fogs • Good location to study long-range transport From Report on the state of the environment in China 2008.

Measurements at Mt. Heng (1269 m a.s.l. 14 March – 1June, 2009) Speices

Gases

Aerosol

Cloud/Fog Meteor. Parameters

Techniques/Instrements

Resolution

O 3 , CO, SO2 , CO2

TEI analyzers

30s

NO, NO2

TEI 42I + Blue light converter

30s

NOy , NH3

TEI 42CY + Mo converters

30s

HNO 3 , PNO3 -

TEI 42CY + Mo converters +Filters

30s

HCl, HNO 3 , SO 2 , NH3 VOCs OVOCs

ChemComb/URG3000K denuder Canister + GC/FID GC×GC - FID/MS

12h episode day episode day

PM2.5 Mass

TEOM 8500

5min

PM10 Mass BC (880nm and 370nm) σsp (520nm) Particle number spectrum (10-10000nm) PM2.5 ions

TEOM 1400 Magee 21 Ecotech M9003 WPS 1000 URG + IC

5min 5min 1min 8min 24h

PM2.5 samples

Teflon and Quartz filters

24h

PM10 samples Segregated PM samples pH, EC, ions, trace metels, DOC, organic acids, S(IV), HCHO, H2 O2

Quartz filter MOUDI

24h 24h, sunny days

Temp, Pres, Wind, RH, Solar, TUV, and visibility

CASCC2 Weather Station

1min

The Site at Mt. Heng

Results • Ozone • Dust storms and interactions with pollution • New particle formation/growth •Cloud water composition • Air-mass transport

Ozone pollution at Mt. Heng Moderate pollution was observed on sunny days.

Ozone Mt. Heng

Mt. Tai

140 120

O3

100 80 60 40

y = 0.81x + 60.38

20

2

R = 0.38

0 0

25 50 PAN+Total N

75

A dust event at Mt. Heng The impact of dust storm was observed, with PM10 concentrations exceeding 800 µg/m3.

From MODIS, Apr23

From MODIS, Apr24

Dust event at Mt. Tai in 2007

3月 月31日 日

4月 月1 日

4月 月2 日

Reactions on dust surfaces in the North and South Dust at at Mt. Mt. Tai Heng Dust

Mt. Tai

Paticle formation and growth Mt. Heng

Cloud water composition

Mt Heng (spring) VWM pH = 3.75 range: 2.91~ 6.91

Mt Tai (one year) VWM pH=3.86 range: 2.65 ~ 7.64

Major air masses at Mt. Heng

HYSPLIT4.8 (NOAA/ARL)

5 day 3-D backward Trajectory

Ending point: 1500 m a.s.l.

Cluster analysis with Ward’s method

Major air masses at Mt. Heng

Summary • Comprehensive data were collected at two mountain sites • Serious pollution was indicated (ozone, PM, cloud and rain) • New particle formation frequently occurred • Reactions on dust surfaces were observed • In-depth analyses are ongoing

Acknowledgements • China National Basic Research Program on acid rain pollution and control (973 project 2005CB422203) • HKPU Niche Area Development Scheme (1BB94)

Additional collaboration with Dr. Jeff Collett’s group and Dr. Don Blake’s group

Thank you!

Removal and in-cloud affect the conc. and size of aerosols

Air pollutants Clouds ???

- gases -aerosols (size & comp.) -cloud comp.

Microphysical properties - CCN -cloud albedo (Twomey effect) -cloud life time -semi-indirect -others

Acidic cloud/fog water Frequent cloud/fog events occurred. － 194 samples for 24 events. The cloud water were mostly acidic. pH range: 2.91~6.91 VWM pH = 3.75

7

Max 6.91

pH VWM

6

SO42-,NH4+,

-,

NO3 and

pH

The dominant ions are: Na+.

5

4

3.47 3

Min 2.91 3.11 3.27 4.03 4.12 4.20 5.02 5.12 5.27 pH changes of cloudwater at Mount. Heng in 2009

Date

Particle formation/growth

To study regional pollution in Southern and Northern China and impact on clouds

OH，H2O2 O3等 PM 光化学 城市扬尘、 沙尘暴和水泥工业等

中和作用

NH3

农业施肥 和畜牧业

VOC 工业、交通和植被等 National Basic Research Program on Acid Rain Pollution and Control in China

Project 3: 2005CB422203

Impact of different air masses on cloud compositions at Mt. Tai