摘要
卷云通常存在于6 km以上的高空,由非球形冰晶粒子组成,其对地球系统辐射平衡有着重要的影响作用。原位观测实验表明卷云中存在着大量的空心冰晶粒子,然而在激光雷达观测实验中,由于缺乏合适的正演模型,空心冰晶粒子的存在往往被忽略。本文基于前人的原位观测结果,建立了冰晶空心度与冰晶长度的经验关系式,克服了传统空心冰晶模型中采用固定空心度的缺点。文中详细介绍了光束分裂物理光学近似方法的推导和空心冰晶后向散射特性的计算过程。仿真研究发现532 nm和1064 nm波长下冰晶粒子的退偏比和色比与粒子大小具有依赖性,其中色比随着粒子增大而单调递减。
Cirrus clouds,typically found at altitudes above 6 km,consist of non-spherical ice crystals and play a crucial role in the earth's radiation balance.Previous in-situ observation experiments have revealed a significant presence of hollow ice crystals in cirrus clouds.However,due to the absence of appropriate forward model,the existence of these hollow ice crystals is often overlooked in lidar observation studies.Based on prior in-situ observations,this paper establishes an empirical relationship between the hollowness and the length of hollow ice crystals,addressing the limitations of the fixed hollowness assumption used in previous hollow ice crystal models.The derivation of the physical optics approximation method based on beam-splitting and the calculation process for the backscattering properties of hollow ice crystals are introduced in detail.The simulation results show that both the wavelength depolarization ratio and the color ratio of ice crystals at 532 nm and 1064 nm are dependent on crystal size,and especially,the color ratio of ice crystal dooecreases monotonically with the increase of crystal size.
作者
祝宣浩
刘东
ZHU Xuanhao;LIU Dong(Key Laboratory of Atmospheric Optics,Anhui Institute of Optics and Fine Mechanics,HFIPS,Chinese Academy of Sciences,Hefei 230031,China;Science Island Branch of Graduate School,University of Science and Technology of China,Hefei 230026,China;Nanhu Laser Laboratory,National University of Defense Technology,Changsha 410073,China)
出处
《大气与环境光学学报》
2025年第3期367-384,共18页
Journal of Atmospheric and Environmental Optics
基金
安徽省自然科学基金资助项目(2208085UQ01)
合肥研究院院长基金拔尖人才培育项目(BJPY2021A03)。
关键词
卷云
冰晶
非球形粒子散射
激光雷达
cirrus cloud
ice crystal
scattering properties of non-spherical particle
lidar
