Interactions between surface cold pools and mesoscale convective systems: Sensitivity to land surface processes and initial conditions

Description

This study investigates the interaction between surface cold pools and mesoscale convective systems (MCSs). Specifically, we examine the properties of surface cold pools that influence the evolution and sustainability of MCSs. High-resolution mesoscale numerical simulations (at ~ 1 km) are performed using the Weather Research and Forecasting (WRF) model with major MC3E cases. The sensitivity of numerical simulations of MCSs to land surface schemes and initial conditions is evaluated. It is found that accurate numerical simulations of MCSs and surface cold pools are sensitive to land-surface processes. Assimilation of surface Mesonet observations helps improve the representation of surface cold pools in numerical simulations. Further diagnoses of the model results indicate that the sustainability of a surface cold pool-associated outflow boundary is a major mechanism that determines the maintenance and development of multi-cell MCSs. Surface heat and moisture fluxes are strongly associated with the sustainability of the convection and outflow boundary.