In this presentation, data sets from three different field campaigns are analyzed to investigate characteristics of the nocturnal boundary layer and the evolution low level jets. The field campaigns considered include the Lower Atmospheric Boundary Layer Experiments (LABLE), conducted in northern Oklahoma in 2012 and 2013, the 2015 Plains Elevated Convection at Night (PECAN) experiment that targeted central Kansas as study area, and the Perdigao campaign which took place in summer 2017 in Portugal. Observations are also supplemented by output from three-dimensional simulations with the Weather Research and Forecasting (WRF) model. In the US Central Plains low level jets frequently formed which influences the turbulence and thermodynamic structure of the nocturnal boundary layer. The spatial evolution of the low level jets over the gently sloping terrain was also found to play an important role. At the Perdigao site, which is located in a valley between two parallel ridges, flow patterns were very complex with multiple vertical layers and wave patterns were also common features.
Dr. Petra Klein earned a Diploma in Physics (1993) and a Ph.D. in Civil Engineering (1999) from the University of Karlsruhe in Germany. After a Post-Doc appointment at ETH Zuerich in Switzerland, she joined the School of Meteorology at the University of Oklahoma, in 2002 as Assistant Professor. She was promoted to Associate Professor in 2016 and to Professor in 2017. She began her current position as Executive Associate Dean of the College of Atmospheric and Geographic Sciences at the University of Oklahoma in August 2017. She has participated in numerous measurement campaigns and is an author of 50 peer reviewed papers. Her awards include an NSF Career Award in 2006 and the Edith Kinney Gaylord Presidential Professorship in 2009. She serves on the UCAR Board of Trustees (2015) and in this role she serves on the Executive Committee of the Board of Trustees (2016) and as Co-chair of the Board of Trustees (2017). Her primary research area is boundary layer meteorology. Particular research interests include tropospheric pollution problems, flow and turbulence characteristics in urban areas, wind-tunnel modeling of geophysical flow phenomena, atmospheric measurement techniques, stable boundary layers, and low-level jets.