How does storm surge work? (Miami: tornado, houses, banks)

[randian]

Is it an avalanche of water slamming into the coastline line a tsunami, or is it more like being in a giant tub that slowly fills over the course of a day?

[sunrico90]

Storm surge is simply water that is pushed toward the shore by the force of the winds swirling around the storm. This advancing surge combines with the normal tides to create the hurricane storm tide, which can increase the mean water level 15 feet or more. In addition, wind driven waves are superimposed on the storm tide. This rise in water level can cause severe flooding in coastal areas, particularly when the storm tide coincides with the normal high tides. Because much of the United States' densely populated Atlantic and Gulf Coast coastlines lie less than 10 feet above mean sea level, the danger from storm tides is tremendous.

The level of surge in a particular area is also determined by the slope of the continental shelf. A shallow slope off the coast (right, top picture) will allow a greater surge to inundate coastal communities. Communities with a steeper continental shelf (right, bottom picture) will not see as much surge inundation, although large breaking waves can still present major problems. Storm tides, waves, and currents in confined harbors severely damage ships, marinas, and pleasure boats.

[randian]

I know what storm surge is. A simpler way to ask my question is "during a storm surge, how likely is structural damage caused by huge waves slamming into buildings, and how does that compare to damage caused by simple submersion?"

[Lindsey_Mcfarren]

From what they have said on the news, storm surge has taken away alot of the beaches along the East coast of Florida. They have shown video of it beating away at the coast, I would imagine it would HAVE to be alot stronger then simple submersion. The waves are higher and stronger.

[mccarley]

Go to this site.
gulflive.com: The Mississippi Press
Look at the Aug. 30 2005 edition of the newspaper. Its the last on the list. Its a very good education on storm surge and hurricanes.

[tallrick]

My grandfather went through the hurricanes of 1926, 1935 and 1960 and told me his experience of storm surge. The wind and rain come first, then the water slowly rises from the ocean. wind driven waves are on top of it. The problem is that there is no way to keep the water from rising and some people just drown in their homes as the water can rise 10-20 feet in a matter of minutes. He never said anything about a tidal wave, but a friend of his actually was in a home that floated inland and ended up in a hardwood hammock west of US-1. In today's Miami the storm surge would knock out power, and cause objects to float around everywhere. Even caskets were comming out of the ground in 1926. I would never want to be in a storm surge, too much debris floating around and wind and waves pushing it around.

[sapling]

It's not generally a "huge, single wave", though I won't say that's impossible. The problem is, though the overall water level is rising, not coming in as a wave, there's a huge amount of wind that is making its own waves. So if you submerge your house up to 6 in of water and then have hurricane force winds causing 2-3 foot waves to smack into your house repeatedly, it can cause a lot of damage.

I drove through the coastal areas of my city after a major hurricane a few years back, and all I can say is that convinced me I NEVER want to live directly on the coast (I live about 10 minutes inland). 90% of the houses were completely gone - the only indication you had there was a house there, ever, was the concrete slab of the foundation it had once stood on.

[ara^bess]

Originally Posted by randian

I know what storm surge is. A simpler way to ask my question is "during a storm surge, how likely is structural damage caused by huge waves slamming into buildings, and how does that compare to damage caused by simple submersion?"

It depends on where you live and what body of water 'type' is most likely to cause you problems. I used to live on the beach...this would be something much like a tsunami, due to the ocean tide itself, accompanied by heavy tornado strength winds.

Now, I live on a river....this would be more like a surge that would cause the bathtub flooding effect you were referring to. If the bathtub effect doesn't come with extreme winds or a tornado....it would just be flood damage....a continual rise of water until it crested and eventually receded back to it's normal banks. This is true for MOST of Florida, other than your coastal areas.

I hope that helped!