Today at Radikite, the kitesurfing school in Tarifa, we want to talk to you about coastal breezes, the famous thermal winds that save many of our kite sessions during spring and summer.
During the warm seasons in areas close to the coast, a meteorological phenomenon occurs where air circulations are established due to the daytime heating and nighttime cooling of the land and the sea. The temperature contrast between the sea and the land generates local low-pressure gradients, but sufficient enough to provide us with a good day of kiting.
There are two types of breezes:
Brisa marina o virazón: Circulación de aire desde mar a tierra
Air circulation from the sea to the land. You have probably heard a kiter talking about thermal winds at the beach, well, this is what they are referring to. Let’s understand it a little better…
During the day, as the sun heats up the land, a stream of air from the sea appears over the coastal strip. As the morning progresses, it grows in thickness and horizontal extension towards the mainland. Subsequently, as the breeze develops, it extends further out to sea as well.
This breeze usually penetrates inland between 20 and 50 kilometers in mid-latitudes, while in the tropics, it can reach up to 300 kilometers.
The sea breeze consists of a surface wind current and a weaker but vertically thicker upper current, known as the return flow or reflux, which completes the cycle.
The wind intensity can range from Beaufort force 3 to 4 (7-16 knots), occasionally reaching force 5 (17-21 knots) in some cases. Generally, the maximum wind speeds are reached shortly after the maximum temperatures are recorded.
It is important to consider other factors such as topography, orography, or local conditions for this phenomenon to occur.
Land breeze or “terral”:
Air circulation from the land to the sea. As the sun sets, the opposite of the “virazón” occurs. The land begins to cool down, while the sea remains warm, causing the air circulation to change direction, establishing the “terral,” but with less intensity than the “virazón” (force 1-2).
The terrain’s topography, orographic features, or soil types can also influence the behavior of land breezes, and in some cases, even nullify them.