Proxigean Spring Tide

Stayed up all night Wednesday to improvise a Kayak-Shelter, then spend all day yesterday paddling a K-1 kayak.  Now, my entire body aches.

Hope to paddle K1 more, it forces me to pay close attentions to details in body postures, blade angle, balance, and even trim.  

Anyway, I just screwed up in reading the calendar and fooled Dennis into giving me another day on his weekend :)  Good thing he is so knowledgeable, turns out new moon and full moon doesn't make much of a difference.  What REALLY makes a difference, is the Proxigean Spring Tide that only occurs once every 19 months.

(Quoting the Astronomy Cafe)

The Proxigean Tide occurs when the Moon is at its closest point in its orbit to the Earth and in its New or Full Moon phase. At this time, its tidal effect on the Earth is maximum. Tidal gravitational forces vary as the third power of the distance between Earth and Moon, so even a small difference in distance can translate into a big effect. The orbit of the moon varies from a distance of 356,500 to 406,700 kilometers with an average distance near 380,000 kilometers. The variation between the maximum and minimum distances results in tidal force changes of a factor of 1.2 times the average tidal forces.

The times when this will happen often coincide with major coastal flooding events. Between 1997 and 2020 there will be 102 times when this will happen. You can see the list by looking at Fergus J. Wood's book Tidal Dynamics published in 1978 by D. Reidel Publishing company, Dordrecht Holland. There are tables computed by van Flandern at the U.S. Naval Observatory. Here is a short list of the most extreme events based on the time between perigee and syzygy being less than 5 hours:

PST Date:

3/11/2003 (N) 

1/10/2005(N)

2/28/2006 (N)

12/12/2008 (F)

1/30/2010 (F)

3/19/2011 (F)

5/6/2012 (F)

6/23/2013 (F)

8/10/2014(F)

9/28/2015(F)

11/14/2016(F)

5/25/2017 (N)

1/2/2018 (F)

7/13/2018 (N)

8/30/2019 (N)

10/16/2020 (N)

12/4/2021 (N)

1/21/2023 (N) 

New Moon is pretty bad because both the Sun and the Moon are on the same side of the Earth, and with the Moon near its closest point to the Earth, the tide- making potential is highest. I will probably not plan to be on the beach on the above dates!