(CNN Spanish) — That is a weather phenomenon Historically It is associated with disasters, floods and general rain damage. It is called “cold drop” in Dana and colloquially.
Despite this association, the DANA is far from being synonymous with catastrophe, rather, it is an occasional event in the Mediterranean between June and October. As it explains National Meteorological Institute of Spain (INM).
What is it about? Next, we give an explanation of this phenomenon.
What is Dana or “Cold Drop”?
INM points out that DANA is an acronym for isolated depression at high levels.
A DANA is “an isolated depression (or storm) at upper atmospheric levels formed by cold air.”
Remember that in the atmosphere, a depression is “an area where the atmospheric pressure is lower than that of the surrounding air”. Complutense University of Madridwhich usually creates Cloud, rain and wind.
Isolation depression occurs more frequently in Dana.
Why the alleged isolation at higher levels? This depression emanates from a belt of winds established in the troposphere and lower stratosphere. These belts may be polar jets or subtropical jets where the air is cooler, INM says.
These jet air currents usually move around the Earth, but their movement is not in a straight line, but sometimes so pronounced that a part of the air mass is choked and cut off, isolating itself from the original flow. INM explains.
Disconnected and isolated from the original jet, this cold air mass floats over DANA and lower levels, where it can produce precipitation and strong winds.
“If one of these waves or ridges (troughs, in meteorological jargon) gets too big, it becomes strangled and forms an isolated cold depression or cold drop. Remember, a cold drop is polar air that floats down the latitudes. Usually that cold air is encroached upon,” says The. INM.
The INM stresses that DANA is not synonymous with a natural disaster, as it is an occasional occurrence in summer and autumn in areas such as the Mediterranean.
A Dana can have severe consequences due to strong rain and wind, but this is not always the case. In fact, there are fewer times when DANA can do massive damage I.N.M.
Dana, therefore, should not be a cause for pointless alarm, but caution and caution.