Mesoscale Motions Over the Plains from MST Radar Observations

本研究的目的是研究MST/ST雷达观测在中尺度环流方面的应用。特别是，位于伊利诺伊州香槟附近的平地雷达的观测结果将被用来探索三个问题。第一个问题是，需要更好地了解垂直运动的空间和时间尺度之间的关系，特别是关于解释ST雷达测量的垂直运动和天气或次天气尺度环流的关系。伴随这一问题的是，需要确定测量的垂直速度的明显向下偏差的来源。其次，用五波束配置进行的测量现在已经可用，并将用于研究重力波。将使用案例研究和水平动量垂直通量等特征的统计摘要来描述中尺度运动的来源机制和不同背景天气条件的影响。此外，它们还将有助于解释水平运动的方差谱。第三，来自Flatland的数据将与附近的其他中尺度观测系统相结合，例如由NOAA操作的微型气压计阵列和Urbana ST雷达，以提供单一雷达无法提供的中尺度过程的物理洞察。

The object of this research is to investigate the application of observations from MST/ST radars to aspects of mesoscale circulation. In particular, observations from the Flatland radar located near Champaign, Illinois, will be used to explore three issues. The first issue is that there is a need for better understanding of the relationship between the space and time scales of vertical motions, especially relating to the interpretation of measurements of vertical motions by ST radars and the synoptic or sub-synoptic scale circulation. Coupled with this issue is a need to identify the source of the apparent downward bias in measured vertical velocities. Second, measurements taken with a five-beam configuration are now available and will be used to study gravity waves. Case studies and statistical summaries of features such as the vertical flux of horizontal momentum will be used to characterize the source mechanisms of mesoscale motions and the effects of varying background weather conditions. Also, they will help interpret the variance spectrum of horizontal motions. Third, the data from Flatland will be combined with other mesoscale observing systems located nearby, such as the microbarograph array operated by NOAA and the Urbana ST radar, to provide physical insights of mesoscale processes not possible with a single radar.//