项目名称: 基于观测资料和数值模拟的积云夹卷混合过程研究
项目编号: No.41305120
项目类型: 青年科学基金项目
立项/批准年度: 2014
项目学科: 天文学、地球科学
项目作者: 陆春松
作者单位: 南京信息工程大学
项目金额: 25万元
中文摘要: 积云中的夹卷混合过程对云与气候之间的反馈过程以及暖云降水过程有着重要的影响。夹卷混合过程的研究包括夹卷率和混合蒸发机制两个方面,分别为干空气被卷入云内的速率,以及云滴在干空气中的蒸发过程。目前对这两方面的认识处于争论之中,迫切需要对这两方面进行综合研究,并探讨夹卷率对云微物理量、云滴谱型的影响。本项目基于积云飞机观测资料(已获得),利用申请人最近开发的夹卷率估算方法,研究夹卷率对云微物理量、云滴谱型的影响;利用申请人最近提出的一个无量纲数,区分不同的混合蒸发机制,并以该无量纲数为衔接点,综合研究夹卷率与混合蒸发机制之间的关系。利用高分辨率的夹卷混合气泡模式,从微观角度研究夹卷混合过程的机理;模拟研究夹卷率对云微物理量、云滴谱型的影响以及夹卷率和混合蒸发机制之间的关系,并与观测结果结合进行分析。所得结果将有利于改进低分辨率模式中夹卷混合过程的参数化方案,增强模式对气候/天气的模拟和预测能力。
中文关键词: 夹卷;混合;云;观测;模拟
英文摘要: Entrainment-mixing processes in cumulus clouds are very important for cloud-climate feedbacks and warm-rain initiation. Studies on the entrainment-mixing processes have two sides: entrainment rate and mixing-evaporation mechanisms. Entrainment rate is the speed at which dry air is entrained into clouds and mixing-evaporation mechanisms are evaporation processes of cloud droplets in dry air. Until now, understanding of the two sides is still a matter of debate, and it is needed to carry out comprehensive studies on the above two sides and on how entrainment rate affects cloud microphysical properties and cloud droplet size distributions. In this project, based on the dataset of cumulus clouds from aircraft observations, the effects of entrainment rate on cloud microphysical properties and cloud droplet size distributions will be studied with the entrainment rate estimation approach, which was recently developed by the applicant; different mixing-evaporation mechanisms will be distinguished with a dimensionless number recently defined by the applicant, and taking this dimensionless number as a connection between entrainment rate and mixing-evaporation mechanisms, the relationships between the two sides will be studied comprehensively. A high-resolution entrainment-mixing parcel model will be used to study entrainm
英文关键词: Entrainment;Mixing;Cloud;Observation;Simulation