Coastal Flooding | floodzee-informatics

Coastal Flooding - Coastal flooding is sometimes called tidal flooding. It is usually the second most destructive form of flooding. It primarily occurs at the time of the highest spring tides. These occur approximately every 2 weeks all year around. Their natural cycle is influenced by the pull of the moon and all other planets including the sun. These effects are variable and as a result the coastal flood cycle brings higher tides and flooding potential at different times each month and each year.

There are typically four highest spring tides each year coinciding with the winter and summer solstice and the spring and autumn equinox. These occur around Dec 21st Mar 21st Jun 20th and September 21st each year. In addition one of the tidal cycles each month is typically higher than the other. As global warming increases it is likely that instead of 4 high tides per annum we will be exposed to 8, 16, 32 and so on high tide cycles as levels increase.

Coastal flooding is also affected by additional surge from low pressure systems, on shore winds and on shore wave action. These effects typically occur as part of Atlantic storm systems. So coastal flooding can combine with winter storms to cause even more serious flooding. These combined events have also occurred frequently in the past.

Prediction of these combined probability events is additionally difficult to coastal flooding prediction on its own. Therefore coastal flood prediction is the second most important from of flood outlook status and alert.