Convergence zone

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For other uses, see Convergence.
Mesoscale sea breezes in Cuba converge from both coasts to form lines of cumulus.

A convergence zone in meteorology is a region in the atmosphere where two prevailing flows meet and interact, usually resulting in distinctive weather conditions.[1] This causes a mass accumulation that eventually leads to a vertical movement and to the formation of clouds and precipitation.[1] Large-scale convergence, called synoptic-scale convergence, provides weather systems such as baroclinic troughs, low-pressure areas, and cyclones. Small-scale convergence will give phenomena from isolated cumulus clouds to large areas of thunderstorms.

The inverse of a convergence is a divergence.

Large scale[edit]

An example of a convergence zone is the Intertropical Convergence Zone (ITCZ), a low pressure area which girdles the Earth at the Equator. Another example is the South Pacific convergence zone that extends from the western Pacific Ocean toward French Polynesia.

Mesoscale[edit]

Convergence zones also occur at a smaller scale. Some examples are the Puget Sound Convergence Zone which occurs in the Puget Sound region in the U.S. state of Washington; Mohawk–Hudson convergence in the U.S. state of New York; the Brown Willy effect which can be generated when south-westerly winds blow over Bodmin Moor in Cornwall; and the Pembrokeshire Dangler which can form when northerly winds blow down the Irish Sea. They can also be associated with sea breeze fronts.

References[edit]

  1. ^ a b LEUNG Wai-hung (June 2010). "Meteorology Basics: Convergence and Divergence". Hong Kong Observatory. Retrieved November 25, 2015.