• Sea Surface Temperature Gradients and Convective Aggregation
    Convective Aggregation, meaning the clustering of convective clouds, is a key element in tropical dynamics. It manifests in the Intertropical Convergence Zone (ITCZ) and the Madden-Julian-Oscillation (MJO) and is also a prerequisite to tropical cyclogenesis. Convection-permitting numerical modeling studies of radiative convective have shown that convective aggregation occurs also when boundary conditions and forcing (sea surface temperatures (SSTs) and insolation) are horizontally homogeneous, and is then referred to as convective self-aggregation. Still, in nature, equatorial waves, low-level convergence and SST-gradients, are the main drivers of convective aggregation.
    In this numerical modeling study we introduce SST gradients to a convection-permitting numerical model of RCE. With this experimental design we investigate both convective self-aggregation and convective aggregation that is forced through a SST-gradient. We use the ICON spherical limited area model and investigate four different SST-profiles.
    I presented first result at EGU conference 2018 in Vienna with this poster.

  • Tropical dynamics: the role of deep convection in tropical wave generation
    In this main topic of my PhD I investigate the controls of tropical convection on the gravity wave spectrum that it generates. For this we developed a Spherical Limited Area Model, using the non-hydrostatic modelling framework ICON. It is a Aqua Planet with a shrinked radius and characterized by a zonally symmetric gradient in sea surface temperatures, peaking at the central parallel. By that we obtained an experimental framework for testing the sensitivity of convectively generated gravity waves to model characteristics like grid spacing and the parameterization of convection. In this analysis I also included ICON-NARVAL simulations and a NICAM model simulation.
    This work is published in the Journal of Advances in Modeling Earth Systems: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2018MS001390
  • Tornadic supercells in landfalling tropical cylones
    ... is the title of my master's thesis, which I did under supervision of Prof. Roger K. Smith in his group on Tropical Meteorology and Cyclones at the Meteorological Institute in Munich.
    • This video of one of my simulations gives an impression of how a supercells forms and intensifies in a landfalling tropical cyclone, by showing dynamical properties like vertical velocity and vorticity.
    • The plots in the figure below focus on the simulation's tornadic phase and captures well-established stages of tornadogenesis. The plots show 3D-rendering of vertical velocity, vertical vorticity, negative pressure perturbations, rain water content, all of them exceeding suitable thresholds, as well as potential temperature perturbations and winds at the bottom level.