title: Observation of aerosol number size distribution and new particle formation at a mountainous site in Southeast China.
abstract: To quantify the physical/chemical properties, and the formation and growth processes of aerosol particles on mountainous regions in Southeast China, an intensive field campaign was conducted from April to July 2008 on the top of Mt. Huang (1840m above mean sea level). The average particle number concentration was 2.35×103cm-3, and the ultrafine particles (<0.1μm) represented 70.5% of the total particle number concentration. Excluding the accumulation mode particles, the average daytime particle number concentrations were prominently higher than those measured at nighttime, suggesting there was a diurnal pattern of changes between planetary boundary layer and free troposphere air. The aerosol spectra were classified into two categories: the first category (FCS) exhibited a clear diurnal cycle, with relatively higher number concentration (3.19×103cm-3), smaller sizes and air masses from the inland; the second category (SCS) presented less obvious diurnal cycle, with lower number concentration (1.88×103cm-3), larger sizes and air masses from coastal regions. Air mass sources, weather conditions, and new particle formation (NPF) events were responsible for the differences of these two particle spectra. Six NPF events were identified, which usually began at 10:00-11:00 LT, with the estimated formation rate J10in the range of 0.09-0.30cm-3s-1and the growth rate at 1.42-4.53nmh-1. Wind speed, sulfur dioxide and ozone concentrations were higher on NPF days than those on non-NPF days, whereas temperature, relative humidity, concentrations of nitrogen oxide and carbonic oxide were lower on NPF days. Sulfur dioxide and ozone might be main potentially precursor gases for those NPF events. The NPF events at Mt. Huang corresponded closely to a southwest winds. These results are useful for improving our understanding of the main factors controlling the variation of aerosol size distribution and NPF events in this region.
authors.affiliation: Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Xiaoru
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China. Electronic address: yinyan@nuist.edu.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yin
authors.affiliation: Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Zhenyi
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Yongxiang
authors.initials: Y
authors.lastname: Han
authors.affiliation: Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Hao
authors.affiliation: Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Yuan
authors.affiliation: Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Kui
authors.initials: K
authors.lastname: Chen
authors.affiliation: Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Chen
authors.affiliation: Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China; Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Shaofei
authors.initials: S
authors.lastname: Kong
authors.affiliation: Atmospheric Science Division, Desert Research Institute, 2215 Raggio Parkway, Reno, NV 89512, USA.
authors.forename: Yunpeng
authors.initials: Y
authors.lastname: Shan
authors.affiliation: Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Xiao
authors.affiliation: Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing 210044, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Tan
keywords: Aerosols; High mountain; New particle formation; Size distribution; Southeast China