The Observation Study Of Number Concentration And Character Of Atmospheric Ice Nuclei In Huangshan Area

In this study, by using the new type high voltage ice nuclei collector and the new type static vacuum water vapor diffusion cloud chamber, built by author, combined with other atmospheric ice nuclei and meteorological elements observation instruments, the constant ice nuclei and meteorological elements were observed simultaneously at three height of Huangshan area from May to September in2011and from September to October in2012, the results are as below:1. The averaged number concentration of atmospheric ice nuclei of Huangshan on BJT10:00is18.37/L in-20℃activation temperature and adequate moisture conditions,. It appears that the number concentration of atmospheric ice nuclei in Huangshan Mountain area decreases along with altitude increasing and reaches its maximum in spring, minimum in summer and intermediate level in autumn regardless of total nucleation mechanism, condensation nucleation mechanism or deposition nucleation mechanism. At the same time, the standard deviation of the number concentration of atmospheric ice nuclei in total nucleation mechanism is the largest and that in deposition nucleation mechanism is the smallest and that in condensation nucleation mechanism keeps intermediate level. During a day, the number concentration of atmospheric ice nuclei in Huangshan Mountain area reaches its maximum in the afternoon, minimum at night. Compared to the number concentration of atmospheric ice nuclei in the Northern China, which in Huangshan Mountain area seems lower for the same period but higher in the sixties, which could further demonstrate the important role of the contribution of human activities to the number concentration of atmospheric ice nuclei.2. With the rising activation temperature, the number concentration of atmospheric ice nuclei in different nucleation mechanism in Huangshan Mountain area decreases in exponential form. With the increasing of humidity, the number concentration of atmospheric ice nuclei in different nucleation mechanism in Huangshan Mountain area is gradually ascending. For one thing, when relatively water surface is unsaturated and relatively ice surface is over saturated, ice crystal is formed through deposition nucleation. For another, when it reaches to or exceeds the saturated state of water surface, condensation and freezing mechanisms begin to take effect and promote the number concentration of atmospheric ice nuclei obviously. Due to the clean summit of Huangshan Mountain, atmospheric ice nuclei have been conveyed by southwest wind to the summit. When the wind speeds up, the number concentration of atmospheric ice nuclei is driven up. However, from the perspective of individual cases, aerosol transport over long distances from the northeast area has a more significant influence on the number concentration of atmospheric ice nuclei in Huangshan Mountain summit.Different process brings different effect on the number concentration of atmospheric ice nuclei in Huangshan Mountain summit.The number concentration of atmospheric ice nuclei on the top of Huangshan Mountain gradually decreases with the process of precipitation and fog going.Along with the pollution process,the number concentration of atmospheric ice nuclei in Huangshan Mountain summit rises by degrees.Cloudy process doesn’t affect the number concentration of atmospheric ice nuclei in Huangshan Mountain summit significantly.3.The empirical formula of the number concentration of atmospheric ice nuclei in Huangshan Mountain summit in total nucleation mechanism"N=6.12×10-5(-T)3.34(naer,0.5)(-0.00265T+0.0036),the empirical formula of the number concentration of atmospheric ice nuclei in Huangshan Mountain summit in condensation nucleation mechanism N=√2.78×10-5(-T)2.38(naer,0.5)(-0.06T-0.623)[(Si-1)(S0-1)-1]4.3concentration of atmospheric ice nuclei in Huangshan Mountain summit in deposition nucleation mechanism:N=√1.56×10-5(-T)2.27(naer,0.5)(-0.05T-0.612)[(Si-1)(S0-1)-1]3.8...