Toward the definition of “Medicane”

As part of the EU COST Action on Mediterranean cyclones, an initiative was launched aimed at defining “Medicane”, a portmanteau for Mediterranean hurricane. In the literature, the term Medicane has been adopted in different ways, depending on the purpose of the study and the instrument adopted for the analysis. The purpose of this activity is to converge towards a shared definition, which will be able to bring together the numerical and satellite approach, the meteorological and climatological perspectives in a single and complete vision.

Although there is still no consensus on the definition, Medicanes are generally considered to be baroclinic cyclones that evolve into vortices with structural characteristics similar to tropical cyclones, i.e., axisymmetric, deep warm core with a windless center surrounded by strong winds. The synergy between baroclinic instability and diabatic processes is fundamental for the intensification of Medicanes.

Stimulating discussions emerged in some online meetings and in the subsequent debate. While up to now the term Medicane has been used for both cyclones with tropical characteristics and for weaker subtropical cyclones, a certain consensus has been reached in considering the latter category as separate, considering the different convective cloud cover, the fact that a significant part of the energy is received from baroclinic sources and that the area with maximum wind is farther from the center.