Circulation Budgets of Supercell-spawned Tornado-like Vortices

Circulation, and sometimes circulation budgets, have been used by other investigators in both multi-radar studies and in idealized models consisting of Eulerian and/or Lagrangian frameworks in an effort to understand tornado maintenance. Here, an Eulerian circulation analysis was performed for a simulated tornado-like vortex and parent supercell mesocyclone using output from the idealized model, CM1. Starting with a long-lived simulated tornado, several new simulations were performed with different model physics settings (e.g., microphysics) and environments (e.g., weakened low-level shear), resulting in tornadoes of differing intensity and longevity. The circulation analysis was used to investigate the dominant terms in the circulation budget between the different simulations in relation to the tornado lifecycle and associated low-level cold pool behavior.