Evaluation of the Cloud Particle Imager and Investigations of Ice Multiplication

该项目的重点是评估一种名为CPI（云粒子成像仪）的新仪器的性能特征，并将该仪器应用于云中冰晶的机载研究。基于先进的光学设计和复杂的图像处理，CPI可以探测并生成小至几微米大小的云粒子的高分辨率图像，远远超过以前仪器的能力。对于定量云物理研究，CPI不仅要能够探测和形成冰晶图像，还要能够测量它们在空间中的浓度。这种测量需要了解仪器的灵敏度和响应，以及观察到的信号对可调系统参数（如激光束强度、最小可接受粒度和颗粒检测阈值）的依赖性。因此，该项目的第一个目标是进行理论计算、实验室研究和空中测量，旨在评估CPI的性能特征。这项工作将与国家大气研究中心的研究人员合作完成。第二个目标是将CPI应用于具有高浓度冰晶的云区研究。这些研究涉及冰晶倍增的问题，将与新墨西哥矿业与技术研究所的艾伦·布莱斯博士合作进行。该计划预计将导致对CPI的能力和局限性的透彻理解，处理CPI数据的新算法，以及对流云中冰晶的数据，这将使冰晶乘法的不同理论的测试成为可能。

This project is centered on an evaluation of the performance characteristics of a new instrument called the CPI (cloud particle imager) and application of the instrument to airborne studies of ice crystals in clouds. Based on advanced optical design and complex image processing, the CPI detects and produces high-resolution images of cloud particles down to a size of several micrometers, far exceeding the capabilities of previous instruments. For quantitative cloud physics studies, the CPI must be able not only to detect and form images of ice crystals, but also measure their concentration in space. This measurement requires an understanding of the sensitivity and response of the instrument, and the dependence of the observed signals on adjustable system parameters such as the intensity of the laser beam, the minimum acceptable particle size, and the particle detection threshold. Accordingly, the first objective of the program is to carry out theoretical calculations, laboratory studies, and airborne measurements designed to evaluate the performance characteristics of the CPI. This work will be done in collaboration with researchers from the National Center for Atmospheric Research. The second objective is to employ the CPI in studies of cloud regions having high concentrations of ice crystals. These studies bear on the question of ice crystal multiplication and will be conducted in collaboration with Dr. Alan Blyth of the New Mexico Institute of Mining and Technology. The program is expected to lead to a thorough understanding of the capabilities and limitations of the CPI, new algorithms for processing CPI data, and data on ice crystals in convective clouds that will enable the testing of different theories of ice crystal multiplication.