初生对流的地基综合观测和微波辐射模拟研究

Convective initiation, which has a complex trigger mechanism, is an important precursor to the development of strong convective weather. Existing research on its understanding is still very limited. The project will carry out comprehensive observations of convective clouds in southern China using advanced atmospheric measurement equipment, such as total-sky cloud imager, ceilometer, weather radar, wind profiler radar, laser radar, cloud radar, radiosonde and microwave radiometer. Using the identification method for convective initiation, we will build a data set that contains a number of convective initiation cases and continuous improvement. By analyzing of all observation data and carrying out research on fusion algorithms, the macroscopic, microphysical and microwave radiation characteristics of clouds can be obtained when convective initiation happened. To further understand the impact of cloud microphysical structure at convective initiation on passive and active microwave radiation, the simulation method of passive and active microwave radiation will be established, and then the sensitivity tests for the microwave radiation under different cloud droplets phase, concentration and particle size distribution will be done. The research not only can promote the understanding of physical process and radiation characteristics at convective initiation stage, but also can facilitate the short-term early warning for strong convective weather and provide guidance for weather modification operations, which has important scientific significance and application prospects.

初生对流是强对流天气发展的重要前兆，其触发机理复杂，现有的研究对其了解还十分有限。本项目拟联合利用地基全天空云观测系统、激光云高仪、天气雷达、风廓线雷达、激光雷达、云雷达、探空和微波辐射计等先进的探测仪器在华南地区开展对流云的地基综合观测，结合初生对流识别方法，建立初生对流个例集并不断完善。综合分析多种地基观测资料及其融合算法，开展对流初生时云的宏观、微物理和微波辐射特征提取。建立主被动微波辐射传输模拟方法，开展不同云滴相态、浓度和粒径分布下的主被动微波辐射敏感性试验，深入理解初生对流发生时云的微物理结构对主被动微波辐射的影响。这一研究成果能够有效提高对初生对流的物理过程和辐射特性的理解，有助于强对流天气的短时临近预警并指导人影作业，具有重要的科学意义和应用前景。

初生对流是强对流天气发展的重要前兆，其触发机理复杂，现有的研究对其了解还十分有限。本项目依托中国气象科学研究院在龙门云物理野外科学试验基地架设的各类先进的主被动探测仪器连续四年开展对流云的地基综合观测，获得了大量地基观测资料，并建立了初生对流个例集。利用地基全天空云观测系统在全国多个气候区域的历史观测资料，研究了云量和云状自动观测方法，以及对流初生时天空中云的宏观特征变化规律，为对流初生时云的宏观特征分析提供了技术保障。研究了对流初生时云的运动规律、风场的变化趋势及大气能见度的估算方法。开展了基于激光雷达的边界层高度计算方法。分析了不同空气污染情况下的太阳辐射，为低能见度和高污染情况下的辐射提供了技术积累。探讨了利用风云三号D星中的微波温度计（MWTS）和微波湿度计（MWHS）来开展海洋上大气中的云液水和可降水含量的反演方法，力求从云水变化的角度来分析对流的形成过程。深化了主被动微波辐射传输模式PAM-VRT的研发，基于一维变分算法开展了大气温湿度廓线的反演方法研究，并对不同类型探空系统获取的相对湿度进行了对比分析。深入研究了非球形冰晶粒子的微波散射特性，并开展了各种敏感性试验，相关工作已集成到自主研发的快速辐射传输模式ARMS中。这一研究成果能够有效提高对初生对流的物理过程和微波辐射特性的理解，具有重要的科学意义和应用前景。