The Generalized Application of a New Surface Pressure Tendency Equation in Synoptic Weather Systems

摘要

The surface pressure tendency equation (SPTE) is an important theoretical tool in understanding the development of weather systems, with various forms being proposed over the past 100 years. In this study, a new version of the SPTE, which eliminates the explicit or implicit pressure tendency term on the right-hand side, is applied to three typical synoptic weather systems in terms of tropical cyclones, explosive cyclones anticyclones, and two mesoscale systems in terms of squall lines and supercells based on numerical simulations. Results reveal promising performance of the new equation in understanding the surface pressure tendency of three synoptic systems, showing advantages in uncovering their dominant physical processes as well as inherent discrepancies. For the tropical cyclone, the latent heating is largely responsible for the surface pressure fall, whereas the surface pressure rise of the anticyclone is mainly fueled by the upper-level advection of potential temperature. The leading factors for the explosive cyclone intensification demonstrate a transition from mid-level diabatic heating at the early stage to upper-level potential temperature advection related to stratospheric air intrusion during the later intensification period. For the squall line and supercell, however, local breakdown of hydrostatic balance can be as large as similar to 10, and consequently, caution should be taken when the equation is used in mesoscale systems, especially for the supercell. These results suggest that the new SPTE can be well applied in synoptic weather systems, and can provide new insights into their intensity evolutions and contributions of diverse physical processes. Plain Language Summary Surface pressure tendency can reflect the adjustment and evolution of the vertical arrangement of the atmosphere and therefore help us better understand the development of weather systems, or even climate change. A new form of the surface pressure tendency equation (SPTE) is examined and shows the possibility for wider application. The analysis of three typical cases including tropical cyclones, explosive cyclones and anticyclones shows that the new SPTE can unravel the mechanisms of their development. The tropical cyclone is mainly fueled up by deep convection, while the anticyclone is adiabatically fed by the horizontal potential temperature advection. The explosive cyclone can grow up through both advection and latent heating. Though they are all tropospheric phenomena, stratospheric processes are also important in the explosive cyclone and the anticyclone. The new SPTE is a great diagnostic tool, especially for synoptic weather systems. It can be used to dig out the basic characteristics of weather systems and help researchers to compare between different weather systems.