MEDICANES

What Are Medicanes?

The term "medicane," short for “Mediterranean hurricane,” was introduced two decades ago to describe vortices similar to tropical cyclones, occurring in the Mediterranean region. Although medicanes rarely match the intensity of tropical cyclones, they can still cause significant damage through windstorms, floods, and storm surges. Affecting over 500 million people in one of the world's most densely populated regions, medicanes represent a significant environmental risk.

The Science Behind Medicanes

Research suggests that medicanes are sustained by a feedback loop between surface enthalpy fluxes and wind, akin to tropical cyclones. This has led to the broadly accepted view that medicanes are a distinct type of Mediterranean cyclone sharing many physical processes with tropical cyclones. Both exhibit similar features such as weakening after landfall, warm-core structures, weak environmental wind shear, and a decrease in the number of lightning flashes near the center at maturity. However, recent studies have shown that not all cyclones classified as medicanes develop through the same mechanisms as tropical cyclones, as baroclinic instability (typical of common mid-latitude cyclones) may play an important role even in the mature stage.

Defining Medicanes

A major challenge within the scientific community has been the lack of a consistent definition for medicanes. Different criteria used in research and observations have led to varying definitions, making it difficult to compare findings across studies. This inconsistency also complicates the issuance of weather warnings, leading to confusion among weather services and the public.

A New Definition for Medicanes

To address this issue, the MEDICANES project has recently introduced a standardized definition:

"A medicane is a mesoscale cyclone that develops over the Mediterranean Sea and affects its basin. It displays tropical-like cyclone characteristics, such as a symmetric deep warm core, an eye-like feature in its center, and a nearly windless center surrounded by maximum 10-meter wind speeds within a few tens of kilometers."

This phenomenological definition, based on observable structural characteristics, ensures objectivity and consistency in identifying medicanes. The use of Earth Observations (EOs) allows for equal accessibility and reproducibility in models, enhancing collaboration among weather services for issuing accurate warnings.