Start
April 25, 2024 - 3:00 pm
End
April 25, 2024 - 3:30 pm
Categories
Convective Meteorology (Mesoscale Dynamics)Convective Meteorology (Mesoscale Dynamics)
Oluwafemi Omitusa
Characterizing the Effects of Land Cover Heterogeneity on Convective Cells and Precipitation in Houston, Texas
April 25th, 2024
3:00 pm / NWC 1350
Abstract: Urbanization profoundly impacts local meteorology and precipitation processes, as urban landscapes modify heat, moisture, and momentum fluxes in the boundary layer. For example, past modeling studies have revealed that urban areas can enhance rainfall by over 30% through mechanisms such as increased moisture convergence and the urban heat island effect. In addition, the coastal environment has unique mechanisms, such as sea breeze, that control the distribution of convective precipitation. However, few observational analyses utilizing high-resolution meteorological measurements of deep convection in coastal urban environments are available, which limits our process-level understanding of these modeled relationships. In particular, knowledge gaps remain regarding how ambient environmental conditions evolve as convective cells traverse heterogeneous landscapes, as prior works have not examined linkages between the environments of different land cover and convective storm char
acteristics. We address these knowledge gaps by utilizing radar observations, remote sensing, and geospatial analysis to investigate how the urban area of Houston, Texas systematically modulates the characteristics and environments of convective storms compared to its surrounding regions. We utilize observations from the KHGX NEXRAD Level-II data for the Houston area for Summer 2022 to track convective cells and analyze their relationship with both rainfall occurrence and intensity. We also utilize sounding measurements to understand how the near-storm environments and pre-convective conditions vary throughout the lifecycle of convective cells in the urban region compared to surrounding rural/suburban areas. Finally, we examine changes in the dynamics of these cells, highlighting how different areas and environmental conditions influence the development of various precipitation particles, such as rain, hail, snow, or mixed phases. The findings will reveal nuanced insights into urba
n–convection interactions, elucidating the causal pathways fundamental to projected increases in extreme rainfall associated with urban areas globally.