Continuation of Ice Crystal Observations at South Pole Station and Collection of Cloud Microphysical Data on Ross Island in Support of ANTCI and RIME

该项目是对2001年2月至2002年2月期间在南极站收集的100多万个冰晶的大小、形状、浓度和散射相函数的支持的先前研究的继续。这是第一个由南极冰晶的高清晰度数字图像组成的统计大数据集，其中包括子弹花环、萌芽花环、实心圆柱体和钻石尘埃。玫瑰花仅占冰粒数量的25%左右，但约占粒子质量的70%，而钻石尘埃约占粒子数量的30%，但仅占质量的15%左右。作为这一项目的一部分，南极站继续进行的地面微物理数据收集将得到长期(超过24小时)的云微物理和辐射数据垂直剖面的加强，新的系留气球系统将把云粒子成像仪和其他气象仪器提升到两公里的高度。系留气球的数据将提供对南极和罗斯岛云的微物理的第一次洞察，因为在这两个地点之前几乎没有现场云微物理测量。在较低纬度进行的一些理论和实验研究表明，粒子的大小和形状强烈影响云粒子的辐射效应，特别是冰晶。单独的观测以及集体统计数据将大大增加几个同时进行的关于雪、大气中冰晶和地表附近温室气体排放特征的实验。这些数据，加上对云底高度、温度和湿度结构等环境条件的测量，将允许开发云和云颗粒特性的气候学，并开发新的算法，以显著改善大气环流模式中辐射过程的表示。

This project is the continuation of a previous study that supported the collection of the size, shape, concentration and scattering phase function of over 1 million individual ice crystals at South Pole Station during February 2001 and 2002. This first statistically large data set of high-definition digital images of antarctic ice crystals showed that these consisted of bullet rosettes, budding rosettes, solid columns, and diamond dust. Rosettes accounted for only about 25% of the number of ice particles, but comprised about 70% of the particle mass, while diamond dust accounted for about 30% of the number of particles, but only about 15% of the mass. As part of this project, the continued ground-based collection of microphysical data at South Pole station will be enhanced by long-duration (greater than 24 hour) vertical profiles of cloud microphysical and radiation data with a new tethered balloon system that lifts a cloud particle imager and other meteorological instrumentation to an altitude of two kilometers. The tethered balloon data will provide the first insights into the microphysics of clouds at South Pole and Ross Island, since there have been virtually no previous in situ cloud microphysical measurements at either location. A number of theoretical and experimental studies at lower latitudes have demonstrated that particle size and shape strongly affect the radiative effects of cloud particles, and specifically ice crystals. The individual observations, as well as the collective statistics will significantly add to several concurrent experiments concerning the emission characteristics of snow, of ice crystals in the atmosphere, and of greenhouse gases near the surface. This data, together with measurements of environmental conditions such as cloud base altitude, temperature, and humidity structure, will allow the development of a climatology of cloud and cloud particle properties, and of new algorithms to substantially improve representations of radiation processes in general circulation models.