Storm surge is created primarily by the powerful winds of a storm pushing water towards the shore.
Here's a breakdown of the process:
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Wind's Driving Force: The strongest factor in creating a storm surge is the immense power of the wind circulating around a storm (like a hurricane or cyclone). These winds, blowing persistently towards the coastline, essentially drag the surface water along with them.
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Shallow Water Amplification: As the water approaches the shallower coastal areas, the seafloor restricts its movement. This restriction causes the water to pile up, dramatically increasing the water level.
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Storm's Low Pressure (Minor Impact): While the low atmospheric pressure of a storm contributes to a rise in sea level, its effect on the overall storm surge is relatively small compared to the force of the wind. The low pressure allows the sea to bulge upward slightly, but this is less significant.
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Coastal Geography: The shape of the coastline also influences the surge. Funnel-shaped bays or inlets can concentrate the water, leading to even higher surge levels.
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Forward Speed and Angle of Approach: The speed at which the storm moves and the angle at which it approaches the coast impact where the highest surge will occur. A slower-moving storm allows the wind to push water onshore for a longer period, resulting in a higher surge. A storm that approaches perpendicular to the coast is likely to cause a higher surge than one that runs parallel.
In summary, the creation of a storm surge is a complex interaction of factors, with the storm's powerful winds being the dominant force pushing water towards the coastline and causing a dangerous rise in sea level.
