INDIRECT EFFECT OF AEROSOLS ON GLOVAL COOLING

为了评估气溶胶颗粒对气候的间接影响，在日本岩手县Kamaishi矿业公司一个深为430m的废弃竖井中建立的人工云实验系统（ACES）中进行了名为Magic Monkey Project （MMP）的现场实验。2002 ~ 2005年，每年11月进行（NH4）2SO4/NaC1气溶胶粒子数浓度对形成的云滴性质影响的实验。在ACES顶部有两个风扇，在ACES内部产生上升气流，最大速度为1.4[m/sec]。在ACES中，任何适合测量的高度都可以通过从底部到顶部固定的梯子到达。云滴在底部上方30米处可见。在ACES底部，由雾化器产生的硫酸铵和氯化钠气溶胶颗粒进入空气中。根据初步实验的结果，从底部到100米的高度进行了强烈的测量。云滴由几个高度的撞击器取样。在ACES内部，底部的温度非常稳定，大约在13.0摄氏度左右。ACES的温度曲线显示，在ACES底部上方30-50m处，也就是云层开始形成的地方，温度递减率很小。当在底部产生硫酸铵和氯化钠等气溶胶颗粒时，云滴的数量浓度增加，直径减小，液态水含量几乎保持不变。在影响气候变化的参数中，气溶胶的间接效应是不确定性最大的一个。虽然这里得到的结果被设想用于一般循环模型（GCM），但我们不能直接使用这些结果。本文还考虑了对GCM模型所得结果的修正过程。

For evaluation of indirect effects of aerosol particles on climate, field experiments, named with Magic Monkey Project (MMP), were carried out in Artificial Cloud Experimental System (ACES) established in an abandoned vertical shaft with 430m depth in Kamaishi Mining Co. in Iwate pref., Japan. The experiments evaluating the influence of the number concentration of (NH4)2SO4/NaC1 aerosol particles on the properties of resulting cloud droplets were performed in November every year from 2002 to 2005.At the top of ACES there were two fans which made updraft inside ACES at the maximum 1.4[m/sec]. In the ACES any favorable altitude for measurement are accessible by ladders settled from the bottom to the top. Cloud droplets were visible around 30m above the bottom. Aerosol particles of ammonium sulfate and sodium chloride were generated at the bottom of ACES by atomizers into the air. According to the results obtained in the preliminary experiments intense measurements were carried out between the bottom and the altitude of 100m from there. Cloud droplets were sampled by impactors at several altitudes.Inside ACES the temperature is very stable around 13.0 degree Celsius at the bottom. Temperature profiles in the ACES showed that temperature lapse rates were small around 30-50m above the bottom of ACES where cloud generation started. When aerosol particles, such as ammonium sulfate and sodium chloride, were generated at the bottom, the number concentration of cloud droplets increased and their diameter decreased keeping the amount of liquid water contents almost constant.Among the parameters influenced to change the climate, the indirect effect of aerosol is the one with largest uncertainty. Although the results obtained here are envisioned to be used in a general circulation model (GCM), we can not use those result directly. The procedure to modify the obtained results for GCM model was also considered.