What causes a storm surge?
As the Environment Canada weather warning indicates, a storm surge is caused by a combination of factors. • The intensity and size of the surge depends on the strength of the winds. Most storm surges occur during hurricanes and usually the stronger the hurricane, the higher the storm surge. • Low pressure acts like a vacuum, creating taller waves and raising the sea level. • The direction of the wind is important, wind blowing on to the coastline pushes water inland, wind blowing along the coast (as is sometimes the case in a hurricane) pushes the water along the shore. • A lower elevation (as in Bangladesh, which is often threatened by storm surges) means the storm can move water further inland. • The slope of the sea bottom can also magnify a storm surge under certain conditions. • Higher tides at the time of a storm surge sometimes called storm tides produce surges that can be 50 per cent higher than normal high tides. How dangerous is a storm surge? The U.S. National Ocean and Atmo
