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，有能力影响它们所在的大范围天气系统。这一研究奖将为一个合作的研究团队提供资金，以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暴风雪中雪花的轮廓，以及模型是否正确地表示了雪。观测和模型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进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。学生们将接受教育和培训，以确保下一代科学家的发展。研究团队计划将降雪的空间和垂直分布的真实观测与数值模型中的表示进行对比，并寻求量化任何差异对风暴演变的影响。其目标是更好地确定三个在气象上截然不同的高纬度气象极端(阿拉斯加、挪威和瑞典)的微物理和动力过程之间的关系。研究的观测部分将包括使用多角度雪花相机对雪花统计数据进行现场测量，以及使用现有的卫星雷达降雪恢复方案从雷达进行遥感。这项工作的建模方面将使用Harmonie、ECMWF-IF和WRF系统进行。该项目将涉及三个主要目标：1)量化每个地点具有不确定性的降雪微物理性质的真实世界垂直廓线，2)比较不同天气条件下降水性质垂直廓线的观测值及其在数值模式中的表示，以及3)评估模拟和观测降水廓线的差异对每个地点预报风暴事件的潜在涡度修正的影响。

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.