Date of Award
Master of Science
Geological and Atmospheric Sciences
During the spring and summer months, convective precipitation is a common occurrence across the central United States. This frequent precipitation often comes in the form of mesoscale convective systems (MCSs), which provide a large amount of the necessary water to the agricultural industry of the region. MCSs, which require large amounts of moisture and wind shear to form, are often fueled in this region by the Great Plains Low-Level Jet (LLJ). These phenomena are responsible for a large majority of the moisture transport into the region and are a main ingredient in summer MCSs. While numerical weather prediction has improved greatly in recent years, accurate forecasting of the LLJ still remains a challenge. Therefore, a further understanding of LLJ simulation is needed to better predict MCSs. To understand how models can simulate the LLJ, atmospheric conditions with the planetary boundary layer (PBL) must be analyzed and understood within numerical models. Parameterization is important in representing small-scale processes and closing systems of dynamic equations, but model sensitivity to these parameterization schemes is something that has not been greatly explored. This work focuses on investigating how three different PBL schemes, the Mellor-Yamada-Janjic (MYJ) scheme, the Mellor–Yamada–Nakanishi–Niino (MYNN) scheme, and the Yonsei University (YSU) scheme, impact the simulation of the PBL and the impact those conditions have on LLJs.
Garberoglio, Michael, "Sensitivity of boundary layer characteristics and related low-level jet behavior to planetary boundary layer schemes in the WRF for several MCS cases" (2020). Graduate Theses and Dissertations. 18129.