Sea breeze

For the amusement park, see Seabreeze Amusement Park.

A: Sea breeze, B: Land breeze

A sea-breeze (or seabreeze) is a wind from the sea that develops over land near coasts.

Because it is a transparent liquid the sea is warmed by the sun to a greater depth than the land. The sea therefore has a greater capacity for absorbing heat than does the land and so the surface of the sea warms up more slowly than the land's surface. As the temperature of the surface of the land rises, the land heats the air above it. The warm air is less dense and so it rises. This rising air over the land lowers the barometric pressure by about 0.2%. The cooler air above the sea then flows towards the land into the lower pressure, creating a cool breeze.

Sea-breezes occur most often in mid-summer when there is a large difference between the temperature of the air over the land and the temperature of the air over the still cold sea. Sometimes in early summer relatively warm air flowing into the area over a cold sea can create advection fog. The sea-breeze effect can pull this fog on to the land near the coast. 'Haar' is the colloquial term for these conditions in the parts of Scotland and Northeast England, which are near the North Sea.

A sea-breeze front is a weather front created by a sea-breeze. The cold air from the sea meets the warmer air from the land and creates a boundary like a shallow cold front. When powerful this front creates cumulus clouds, and if the air is humid and unstable, cumulonimbus clouds, the front can sometimes trigger thunderstorms. At the front warm air continues to flow upward and cold air continually moves in to replace it and so the front moves progressively inland. Its speed depends on whether it is assisted or hampered by the prevailing wind. At night, the sea-breeze usually vanishes but it can occasionally reverse itself into a land-breeze, sometimes causing showers or even thunder-showers, over the water.

Sea-breezes in Florida

Thunderstorms caused by powerful sea breeze fronts frequently occur in Florida, a peninsula surrounded on both the east and west by the Atlantic Ocean and Gulf of Mexico, respectively. No matter which direction the winds are blowing, they are always off the water, thus making Florida the place most often struck by lightning in the United States, and one of the most on Earth. On especially calm days with little prevailing wind, sea-breezes from both coasts may collide in the middle, creating especially severe storms down the center of the state. These storms also tend to produce significant hail due to the tremendous uplift it causes in the atmosphere. In Florida, a sea-breeze pushed by prevailing winds may also continue past the land and out over the water at night, creating spectacular cloud-to-cloud lightning shows for hours after dark. ucks