Oleg Zabluda's blog
Wednesday, October 31, 2012
 
Hurricane Sandy happened right around Full Moon, when lunar and Solar tides add up. Tidal forces are proportional to...
Hurricane Sandy happened right around Full Moon, when lunar and Solar tides add up. Tidal forces are proportional to the mass and inversely proportional to the cube of the distance

solar mass/mass of the Moon = 27M
the Moon is 400x closer then the Sun. 400^3=64M
which makes lunar tides 64/27=2.4 times larger then solar (~40% diff).

If the Distance to the Moon is the same, the tide when the Moon is in syzygies (Full/New), when tides add, is 2.4 times larger than when the Moon is 90 deg to the side (almost, but not quite when the Moon is in Frist/Last Quarter), when tides subtract.

Full Moon was on Oct 29, 2012, when the Moon, luckily, was pretty far 403229 km away, almost as far as it can possibly be (406528 km, like Nov  1, 2012 perigee of 406049 km). The closest Full Moon is 356898 km, making this lunar tide (403229/356898)^3=1.4 times smaller then it could have been, but Sun tide stays almost constant (differs at most by 1.03^3=10%). 

Also see  May 5, 2012 Supermoon 
https://plus.google.com/112065430692128821190/posts/d27aYvbzLDw

In NYC Battery park, high tides (measured from the lowest tide) were:
May 05, 2012 - 6.3 ft
Oct 29, 2012 - 5.4 ft
1.4x ration from above can be obtained if measured from 6.3/2=3.15.

http://tidesandcurrents.noaa.gov/noaatidepredictions/NOAATidesFacade.jsp?Stationid=8518750


http://jgiesen.de/moon/FullMoon/
http://www.fourmilab.ch/earthview/pacalc.html
http://jgiesen.de/moon/FullMoon/

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