Collaborative Research: Impact of Snowfall Processes on Potential Vorticity Generation in High-Latitude Snow Events

降水过程，如蒸发和凝结，有能力影响它们所处的大尺度天气系统。该研究奖将为研究人员合作团队提供资金，研究降雪过程如何影响整体风暴演变。这项研究将利用地面仪器、遥感和数值模拟来更好地了解风暴中雪花的轮廓，以及这些模型是否正确地代表了雪。观测和模式之间的差异将表明降雪过程在风暴事件中的相对重要性。该奖项的结果应该是改善天气和气候目的的建模，并加强美国、挪威和瑞典之间的国际科学合作。学生将受到教育和培训，确保下一代科学家的发展。研究小组计划将实际观测到的降雪的空间和垂直分布与数值模型中的表现进行对比，并试图量化任何差异对风暴演变的影响。目标是更好地确定三个气象上不同的高纬度极端天气（阿拉斯加、挪威和瑞典）的微物理过程和动力过程之间的关系。该研究的观测部分将包括使用多角度雪花相机进行雪花统计的现场测量，以及使用现有卫星雷达降雪检索方案进行雷达遥感。工作的建模方面将使用HARMONIE、ECMWF-IFS和WRF系统执行。该项目将解决三个主要目标：1)量化每个站点具有不确定性的真实降雪微物理特性垂直剖面；2)比较不同天气条件下降水特性垂直剖面的观测值及其在数值模式中的表示；3)评估每个站点模拟和观测降水剖面的差异对潜在涡度修正预测风暴事件的影响。

Precipitation processes, such as evaporation and condensation, have the ability to affect the large-scale weather systems in which they are embedded. This research award will provide funding for a collaborative team of researchers to study how snowfall processes affect overall storm evolution. The research will make use of ground-based instrumentation, remote sensing, and numerical modeling to gain a better picture of the profile of snowflakes in a storm and whether the models are representing the snow correctly. Differences between the observations and the models will indicate the relative importance of snowfall processes in storm events. The result of the award should be improved modeling for both weather and climate purposes and enhanced international scientific collaboration between the United States, Norway and Sweden. Students would be educated and trained, ensuring the development of the next generation of scientists.The research team plans to contrast real-world observations of the spatial and vertical distributions of snowfall with the representation in numerical models, and seek to quantify the impacts of any differences on storm evolution. The goal would be to better define the relationships between microphysical and dynamical processes for three meteorologically distinct high-latitude meteorological extremes (Alaska, Norway and Sweden). The observational component of the research will include in-situ measurements of snowflake statistics using the Multi-Angle Snowflake Camera and remote sensing from radars using an existing satellite radar snowfall retrieval scheme. The modeling aspect of the work would be performed using the HARMONIE, ECMWF-IFS, and WRF systems. Three main objectives will be addressed in the project: 1) Quantify real-world vertical profiles of snowfall microphysical properties with uncertainties at each site, 2) Compare observations of the vertical profile of precipitation properties with their representation in numerical model for different synoptic conditions, and 3) Evaluate the impact of discrepancies in modeled and observed precipitation profiles on potential vorticity modification for forecast storm events at each site.