From Glossary of Meteorology
(Redirected from Meddies)
A short form for Mediterranean Eddy.
Meddies are salt lenses containing high amounts of original Gibraltar Outflow Water in their interior. With spatial scales smaller than the internal Rossby radius, they belong to the energetic class of submesoscale coherent vortices. They rotate clockwise (anticyclonically) like solid bodies and are encapsulated by strong contrasts (gradients) of water masses (properties) and a sharp vorticity front at their periphery. Meddies interact with partner vortices, depending on their geographical position and eddy population. Spontaneous Meddy release represents random salt sources within the Mediterranean salt tongue and questions a large-scale advection–diffusion salt balance in the North Atlantic. Typical Meddy scales and properties include diameters of ∼50–80 km, a vertical extent of ∼600–1400 m, a drift velocity of ∼2–3 cm s-1 (with occasional stalls), a rotation velocity of ∼20–30 cm s-1, a rotation period of ∼4–10 days, a lifetime of months to two years, and a salinity core contrast of 0.2–1 psu.