Ta-Chih (TC) HSIAO | 蕭大智

Research

In the past years, I have conducted several NSC/MOST projects and can be classified into 3 categories:
Aerosol Instrumentation, Atmospheric Aerosol & Ambient Monitoring, PM & Nanoparticle Toxicity.

Atmospheric Aerosol & Ambient Monitoring:

Cloud Condensation Nuclei, CCN

(MS. Student: Edgar Yeh, James Yeh, W.J. Hsieh; 南海空氣品質國際監測合作計畫/環保署/ EPA-102-FA11-03-A217))

In this study, we present CCN measured near the Biomass-burning (BB) source regions over northern Southeast Asia (Doi Ang Khang, Thailand) and at downwind receptor areas (Lulin Atmospheric Background Station, Taiwan). In this study, the time of 13 – 20 March as part of 2013 spring campaign of the Seven SouthEast Asian Studies (7-SEAS) intensive observation was selected as “golden days” for detail data analyses as DAK was affected by two different weather systems in the early and late stages of this period. The CCN activity of BB aerosols in terms of AR and hygroscopicity (κ value) was investigated and analyzed with the diurnal variation of other variables such as fire counts, particle size, BC mass concentration, and Delta-C values. κ values in Southeast Asian BB source regions based on ground-based measurements are very rare and are valuable to global climate modeling studies and to studies on CCN. These data provide the most extensive characterization of the CCN Activity and BC Mass Concentrations of BB aerosols in SouthEast Asia (SEA) until now.

Ta-Chih Hsiao*, Wei-Cheng Ye, Sheng-Hsiang Wang, Si-Chee Tsay, Wei-Nai Chen, Neng-Huei (George) Lin, Chung-Te Lee, Hui-Ming Hung, Ming-Tung Chuang, and Somporn Chantara. Investigation of the CCN Activity, BC and UVBC Mass Concentrations of Biomass Burning Aerosols during the 2013 BASELInE Campaign. Aerosol and Air Quality Research, 2015 Accepted.
Ta-Chih Hsiao*, Neng-Huei Lin, Si-Chee Tsay, Sheng-Hsiang Wang, Zhong-Sin Ye, Wei-Cheng Ye, An Overview of Microphysical Properties of Biomass Burning Aerosols during 2013 BASELInE Campaign, 2014 International Aerosol Conference, Busan, Korea, Aug. 28–Sept. 2, 2014.

Atmospheric Aerosol Optical Properties

(MS. Student: Edgar Yeh, James Yeh, W.J. Hsieh; 鹿林山與偏遠離島背景測站參與國際科技研究及操作維護/環保署/ EPA-103-U1L1-02-101)

The Lulin Atmospheric Background Station (LABS, 23.47 ̊ N 120.87 ̊ E, 2862 m ASL) located in the central of Taiwan was constructed in 2006 for investigating the long-range transport of air pollutants. The recently researches suggested that these long-range transported pollutants may reach the vicinity of Taiwan at high attitude (Wai et al., 2008; Sheu et al., 2010; Ou-Yang et al., 2012). In this study, the two key aerosol optical properties for estimating radiation forcing, the Mass Scattering Efficiency (MSE) and Mass Absorption Efficiency (MAE), were investigated. The MSE (or MAE), which means scattering (or absorption) intensity per gram of PM2.5, is defined as slope of correlation between scattering (or absorption) coefficients and corresponding PM2.5 mass concentrations. The data was collected during 2013 to 2014 using nephelometer, Particle Soot Absorption Photometer, Tapered Element Oscillating Microbalance and Scanning Mobility Particle Sizer. The HYSPLIT 5-day backward trajectories were used to classify the biomass burning (BB) events or non-biomass burning (NBB) events. Moreover, the radiation forcing efficiency was also estimated based on these observed aerosol optical properties.

Manuscript entitled: “Characteristics of Aerosol Optical Properties at Lulin Atmospheric Background Station in Taiwan” was in preparation.
Wei-Chung Ye, Ta-Chih Hsiao*, Sheng-Hsiang Wang, Neng-Huei Lin and Si-Chee Tsay, Characteristics of Aerosol Optical Properties at Lulin Atmospheric Background Station in Taiwan, 2015 Asian Aerosol Conference, Kanazawa, Japan, Jun. 24-26, 2015.
Wang, S. H.*, Welton, E. J., Holben, B. N., Tsay, S. C., Lin, N. H., Giles, D., Stewart, S. A., Janjai, S., Nguyen, X. A., Hsiao, T. C., Chen, W. N., Lin, T. H., Buntoung, S., Chantara, S., & Wiriya, W. Vertical Distribution and Columnar Optical Properties of Springtime Biomass-Burning Aerosols over Northern Indochina during 2014 7-SEAS Campaign. Aerosol and Air Quality Research, 2015, 15, 2037-2050.
Andrew M. Sayer*, N. Christina Hsu, Ta-Chih Hsiao, Peter Pantina, Ferret Kuo, Chang-Feng Ou-Yang, Brent N. Holben, Serm Janjai, Somporn Chantara, Shen-Hsiang Wang, Adrian M. Loftus, Neng-Huei Lin, Si-Chee Tsay. In-situ and Remotely-sensed Observations of Biomass Burning Aerosols at Doi Ang Khang, Thailand during 7-SEAS/BASELInE 2015. Aerosol and Air Quality Research, 2015 Accepted.

Hygroscopic Behavior of Fresh and Aged/Long-range transported Biomass Burning Aerosols

(MS. Student: Edgar Yeh, K.C. Chen, James Yeh, W.J. Hsieh)

In this study, we propose

to establish a hygroscopic tandem differential mobility analyzer (H-TDMA) and a hygroscopic coupled DMA and APM system (H-DMA-APM) for studying diameter (volume) changes and mass change due to water uptake;
to establish wet and dry nephelometers for determining the scattering enhancement factor, f(RH), which is the ratio between the scattering coefficients at a certain RH;
to compare and analyze κ evaluated through three different methods (calculated based on GFd, retrieved based on the scattering enhancement factor, f(RH), and the dry PSD, and estimated based on the CCNc measurements with the operation of S-scan.