SEA-BREEZE - KEY PARAMETERS

• Temperature difference between land and sea
  Cool sea adjacent to the warmer land surface
• Low-level geostrophic flow
  Weak geostrophic wind at lower levels favours the development of Sea-Breeze. A weak opposing flow in the lower troposphere (850 hPa) tends to increase the Sea-Breeze circulation.
• Surface winds
  Onshore winds during the afternoon. Further inland wind direction opposing the wind direction at coast.
• Convergence near surface
  Convergence produced by opposing surface winds.

Temperature difference between land and sea

31 May 2001/12.00 UTC - 2-metre temperature on Northern Baltic Sea. Sea surface temperature (not shown) in this case was just above zero on northernmost parts of the Baltic.	31 May 2001/12.00 UTC - Meteosat IR image

Low-level geostrophic flow

13 June 2001/12.00 UTC - 850 hPa wind (barbs) and geopotential height (black) on Iberian peninsula

Surface winds

13 Jun 2001/12.00 UTC - surface synoptic wind observations with an estimated position of Sea-Breeze front (dashed line)	13 Jun 2001/12.00 UTC - Meteosat VIS image

A Sea-Breeze observed on the Spanish south-east coast. The line of the Sea-Breeze front cannot be delineated accurately due to insufficient surface observations, but (almost acute angle) onshore wind is apparent at the coast, while inland the wind direction is more random.

Convergence near surface

	31 May 2001/12.00 UTC - convergence at 1000 hPa, magenta dashed: divergence, magenta solid: convergence

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SUB-MENU OF SEA-BREEZE

METEOROLOGICAL PHYSICAL BACKGROUND

TYPICAL APPEARANCE IN VERTICAL CROSS SECTIONS

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