Numerical investigations of turbulence in Mediterranean cyclone events: insights from the Turbimecs project

The tropical cyclones are one of the biggest hazards to life and socio-economic activities even in the formative stages of their development. Some of their main features, especially in the shape evolution and in the dynamics, are common with events that in recent years are increasingly affecting the Mediterranean basin, defined as Mediterranean Tropical-Like Cyclones (MTLCs), or Medicanes.

In this study, we investigate the spatial and temporal properties of two Medicanes through high spatial resolution (1 km) reanalysis-based numerical simulations, generated using the Weather Research and Forecasting (WRF) model. The events examined are Qendresa (occurred in November 2014) and Ianos (occurred in September 2020), both developing over the Mediterranean Sea.

The WRF reanalyses were also used to conduct sensitivity studies on the parameterizations of atmospheric physics, focusing on PBL, radiation and microphysics schemes.

In order to address the problem in the classical fluid turbulence picture, the results were also analyzed using the Proper Orthogonal Decomposition (POD) method. With the aim of providing a first approach to understand how different contributions, operating on distinct spatio-temporal scales, can influence the local dynamics and the evolution of the medicanes. In addition the analysis will uncover the formation of coherent structures in the extreme event maturation.