Studies on physical-chemical processes of aerosol-cloud interaction

云凝结核（CCN）的活动是由气溶胶的直径，水溶性组分的分数，和表面张力。我们将CCN活动作为这些参数的函数进行量化，并将它们与云形成过程联系起来。A）城市空气中气溶胶CCN活动的控制因素我们使用气溶胶质谱仪、黑碳（BC）仪器和CCN计数器测量了东京气溶胶的化学成分、混合状态和CCN活动。我们发现，厚涂层BC的CCN活性受水溶性化合物的化学组成控制。B）气溶胶-云相互作用的测量我们在春季对日本附近1-2公里处云内外的气溶胶和云粒子进行了飞机测量。我们发现，厚涂层的BC颗粒被有效地吸收到云中，与地面测量结果一致。这也是S ...更多信息 C）云凝结核形成的时间常数根据韩国济州岛的观测资料，我们发现，在几天内从亚洲大陆输送来的气溶胶的云凝结核活动主要受水溶性组分的影响。有机气溶胶表面张力的降低也是导致云凝结核活动的原因之一。同时还对北京附近地区的各种气溶胶进行了云凝结核活性的测量。观测到的云凝结核活动与在东京和济州岛获得的理解是一致的。D）云探测器的校准及其空气动力学特性光散射云探测器使用高精度的标准粒子进行校准。我们对安装在飞机上的探测器周围的气流进行了空气动力学计算，发现云滴的收集效率很高。E）我们使用轨迹模型计算了根据不同CCN浓度预测的云滴尺寸分布。通过数值试验估计了云凝结核-云相互作用的敏感性。少

Cloud condensation nuclei (CCN) activity is determined by aerosol diameter, fraction of water soluble components, and surface tension. We quantified CCN activities as a function of these parameters and related them with cloud formation processes.A)Controlling factors of CCN activities of aerosol in urban airWe measured chemical composition, mixing states, and CCN activity of aerosol in Tokyo using an aerosol mass spectrometer, black carbon (BC) instruments, and a CCN counter. We found that CCN activity of thickly coated BC is controlled by the chemical composition of water soluble compounds. The CCN activity of thinly coated BC is controlled by the thickness of the coating.B)Measurements of aerosol-cloud interactionWe conducted aircraft measurements of aerosol and cloud particles inside and outside of clouds located at 1-2 km near Japan in spring. We showed that thickly coated BC particles were taken up into clouds efficiently, consistent with the ground based measurements. This also s … More hows that BC can be a good tracer to quantitatively study aerosol-cloud interaction.C)Time constant of CCN formationWe showed that CCN activity of aerosol transported from the Asian continent within a few days is controlled mainly by the fraction of water soluble components from the data obtained in Jeju Island, Korea. Decrease in the surface tension of organic aerosol is also estimated to is contribute to the CCN activity. The CCN activity of various types of aerosol was measured also near Beijing. The observed CCN activity is consistent with the understandings obtained in Tokyo and Jeju Is.D)Calibration of the cloud probe and its aerodynamical characteristicsLight scattering cloud probe was calibrated using standard particles with high precision. We made aerodynamical calculations of airflows around the probe mounted on the aircraft and found high collection efficiency of cloud droplets.E)We calculated size distribution of cloud droplets predicted from various CCN concentrations using a trajectory model. Sensitivity of CCN-cloud interaction was estimated by the numerical experiments. Less