Sunday, 22 January 2017
4E (Washington State Convention Center )
The Plains Elevated Convection at Night (PECAN) field campaign took place from 1 June through 15 July 2015. The primary objective of the campaign was to gain a better understanding of conditions and mechanisms contributing to nocturnal precipitation. PECAN focused on the study of nocturnal convection initiation, the internal structure of mesoscale systems, and the wave-like disturbances that occur as a result of these convective storms. Measurements from the Sigma Space Micropulse Lidar MPL-111 located at FP3 in Ellis, Kansas during this project will be summarized alongside a case study of the low level jet event that occurred on 22 June 2015. The Great Plains low level jet is a recurring feature of the summertime boundary layer over the central plains, and is responsible for the influx of heat and moisture important to the initiation and maintenance of convection across the PECAN domain. The Lidar was used mainly to determine the height of the planetary boundary layer, as well as support the other instruments at FP3 and the PECAN domain as a whole. Instrumentation used in conjunction with the Lidar include an MFAS SODAR, 10m, Flux Tower, WeatherPak, and Radiosondes, which are all a part of Millersville University’s Atmospheric Research and Aerostat Facility (MARAF). The MPL-111 has the ability to generate three products that are compiled from thirty second averages: Raw, R2, and Normalized Relative Backscatter. The backscatter plot denotes the location of aerosols, cloud tops and bottoms, and the location of the boundary layer up to five kilometers. These products can be found on the PECAN field campaign website. A case study of the 22 June nocturnal low level jet event is presented. The passage of the jet can be observed in the Lidar data through examining the dissipation of the residual layer and the collapse of the boundary layer. Accompanying wind and surface flux data can be found on the corresponding Millersville University posters (see N. Midzak and J. Hane). Through examination of the data collected at FP3, we hope to expand the understanding of these nocturnal precipitation events in the Great Plains.
- Indicates paper has been withdrawn from meeting
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