NYCB
I just looked up this site..
giss.nasa.gov
Lots of nice pictures, maps, and facts.
I think the overall interpretation of the risks sounds about right.
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Just plodding through the variables...
According to this site the maximum tidal range is about 6 feet.
bluewaterweb.com
Other sources of water to consider are flood water from rain and snow melt.
The weather is an important consideration looking at the shape of the coastline around NYC and Long Island. A strong Easterly or maybe a South Easterly could pile up the sea level quite a bit during a high tide. Atmospheric pressure over the region also contributes. Therefore a storm with stong winds is and important factor.
On top of these factors is the longer term factors of the Eastern States sinking, and the overall sea level rising.
So, all these factors combine or subtract in many ways to giving the possibility of an effect..a Flood. Statistics can be used to define the extent of a worst case scenario "100 year flood".
Trouble is statistics is developed from theory using certain assumptions that may not apply directly to the given conditions. Well, I should say they don't, they may approximate for the purpose of a useful calculation perhaps.
Therefore, one should not be surprised if the "100 year flood" is an under estimation, or in fact it might occur several times more frequently then once every 100 years.
The climate does seem to be changing. This includes rainfall and wind speeds and direction. Recent figures in the UK have shown some startling variations from normal.
Looking at the first link, yes given the other considerations I would be concerned about a flood risk in NYC.
Now, finally, comes the interpretation of the statistics. A useful "rule of thumb" is that the statistical interpretation will be bent out of true proportionately by the amount of financial interest at stake. Thus if i were considering buying a property for several million dollars, I would be very weary of statistical interpretations on the flood risk.
My own property is located at about 300 ft above mean sea level. Some people in the UK got flooded out, had there properties repaired etc, only to be flooded out again a month or two later. Their flood insurance was then either cancelled or the rate put so high they could not afford it.
I reckon 300ft above mean sea level is about right.
I would certainly be weary of anything below about 20 feet above mean sea level. The location of rivers and reservoirs also important considerations regarding a flood risk.
I would not catch the subway in NYC if there was any flood risk that day for sure, with an Easterly storm on its way. Knowing my luck the electricity would fail as the train was between stations.
That is my 15 minute amateur interpretation. -g- |
