If the phenomenon of El Niño appears at the same time as an extraordinary astronomical tide, of the cycle of 4-5 years, the effects add and cause extraordinary levels of the sea which cause floods in the coast. This happened in 1997 when the Isla Damas in Quepos and other great floods throughout the Pacific Coast of Costa Rica occurred.

Terrestrial factors exist in addition, other components that produce variations in the level of sea like:

* tectonic movements of the terrestrial crust,

* variations in the atmospheric pressure,

* water piling up or retirement by wind that blows towards or from the coast,

* heating of waters by phenomena like El Nino and global warming.