In the last few days weve again experienced "storm surge", which is something that caused a great deal of havoc here along the Chesapeake Bay during hurricane Isabel, back in 2003. That seems minimal compared to what has occured in the past few days from New Jersey to New York City and beyond because of Hurricane Sandy.
Storm surge has to do with water rising in response to winds from a storm. Storm surge along ocean beaches is usually larger and more intense than in bays and tributaries, where the intensity is controlled by a number of factors. Not being a Meteorologist, mine will be a loose explanation.
How storm surge occurs in a body of water such as the Chesapeake Bay has to do, not only with a storms strength, but where the storms center is relative to that Bay. The main winds of cyclones in the Northern Hemisphere spin in a counter-clockwise direction, thus a storm traveling on a Northwest track and coming ashore South of the Bay will create winds that move from the Southeast to the Northwest, which is to say up and into the Bay. Isabel traveled just such a path and piled great amounts of water into the Bay, resulting in a large Storm Surge. Many people were severly hit by flooding; some losing their homes to that storm surge, both along the Bay and throughout its major rivers and tributaries. ??
Track of Isabel is South of The Chesapeake Bay. Image from NOAA.Gov
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? Our shop, which is along the water, was badly flooded in Isabel and ever since we have been wary of any major storm that comes up the Atlantic to our area.
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Our workshop after Hurricane Isabel in 2003 (in the early days of digital cameras).
Sandy,unlike Isabel, traveled a Northwest path, but came ashore North of the Bay and the counterclockwise push of water was largely out of the Bay. That is, during the initial impact. As Sandy moved inland part of that circular motion began to push from the Southwest, but with far less impact than Isabel. You may want to play with a compass and piece of paper to illustrate the principle.
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Hurricane Sandys path was North of the Chesapeake Bay. Image from NOAA.gov
Twice, the storm surge from Sandy moved to within a few feet of our shop, causing a lot of stress, but neither time did it quite get inside. We were extremely lucky. From the information I could find I believe that our storm surge was probably about 3 feet above mean high tide. Here are two, very different photos of David and the Annie Buck, one from the first day that the rain bands came ashore, the second taken during the storm, but a short time before the peak of the surge. Notice the differences in, not only the height of the water, relative to the pier, but also how much higher the boats are floating.
An average high tide here is not much higher than this.
This is a dangerous situation. The storm surge has reached a little under 3 feet. If you could see the shorelines, the creek looks much larger than normal.
We were lucky around here. A lot of other people faired far worse and our thoughts are with them. I know that there was a whole lot of damage North of us. Depending upon how bad that damage is, this storm may be remembered for taking the tall ship "Bounty". Like most hurricanes, there are a lot of stories that will come out of it.
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