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Of moon and tides



 
 
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  #1  
Old January 31st 18, 03:16 PM posted to uk.sci.astronomy
N_Cook
external usenet poster
 
Posts: 86
Default Of moon and tides

A quirk of celestial mechanics.
As the last blood-red , blue-moon, super-moon was 31 March 1866 we'll
have to wait 55458 days for the next coincidence of the tides in the
channel , presumably.
I wonder what conjuction of tidal harmonics gives a 55,458 day repeat.

The high tides in ports of a large part of the English channel today are
all the same time. I originally thought there was a problem with big-data
http://www.ntslf.org/storm-surges/la...ast?port=Dover
http://www.ntslf.org/storm-surges/la...?port=Newhaven
http://www.ntslf.org/storm-surges/la...ort=Portsmouth

And from the UK Hydrographic office, high tide times today
Portsmouth,10:53, 23:24
Newhaven, 10:43 , 23:17
Dover, 10:44, 23:09
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  #2  
Old January 31st 18, 04:25 PM posted to uk.sci.astronomy
N_Cook
external usenet poster
 
Posts: 86
Default Of moon and tides

On 31/01/2018 14:16, N_Cook wrote:
A quirk of celestial mechanics.
As the last blood-red , blue-moon, super-moon was 31 March 1866 we'll
have to wait 55458 days for the next coincidence of the tides in the
channel , presumably.
I wonder what conjuction of tidal harmonics gives a 55,458 day repeat.

The high tides in ports of a large part of the English channel today are
all the same time. I originally thought there was a problem with big-data
http://www.ntslf.org/storm-surges/la...ast?port=Dover
http://www.ntslf.org/storm-surges/la...?port=Newhaven
http://www.ntslf.org/storm-surges/la...ort=Portsmouth

And from the UK Hydrographic office, high tide times today
Portsmouth,10:53, 23:24
Newhaven, 10:43 , 23:17
Dover, 10:44, 23:09


Hydrographic Office EasyTide ďpredictions" for 31st March 1866Ö

Portsmouth times LW=04.40 HW=1129 LW=1658 HW=2353
Dover times Lw=0640 HW=1126 LW=1854 HW=2342

so once in a blood-red , blue-moon, super-moon

Now to find out any significance in
55458= 13x54x79
or in terms of 18.61 year or 8.85 year normal tide cycles

  #3  
Old January 31st 18, 05:17 PM posted to uk.sci.astronomy
Martin Brown[_3_]
external usenet poster
 
Posts: 174
Default Of moon and tides

On 31/01/2018 14:16, N_Cook wrote:
A quirk of celestial mechanics.
As the last blood-red , blue-moon, super-moon was 31 March 1866 we'll
have to wait 55458 days for the next coincidence of the tides in the
channel , presumably.
I wonder what conjuction of tidal harmonics gives a 55,458 day repeat.


It is double the named "Short Callipic Cycle" 2I+S = 75.9y 27729.22d

27729.22 x 2 = 55458.44 but according to the catalogue is unnamed.

I = Inex ~29y and S = Saros ~18y

They are the fundamental periodicities that allow you to catalogue
eclipse cycles. It will be interesting to see if the strong tides this
year drive any climatic effects from deep ocean mixing.

http://www.staff.science.uu.nl/~gent...ipsecycles.htm

Inex gives you an eclipse about the same longitude but opposite latitude
and 3x Saros gives you about the same eclipse conditions in about the
same place on the Earth. Or for an overviews and better explanation

https://eclipse.gsfc.nasa.gov/SEsaro...riodicity.html

The high tides in ports of a large part of the English channel today are
all the same time. I originally thought there was a problem with big-data
http://www.ntslf.org/storm-surges/la...ast?port=Dover
http://www.ntslf.org/storm-surges/la...?port=Newhaven
http://www.ntslf.org/storm-surges/la...ort=Portsmouth

And from the UK Hydrographic office, high tide times today
Portsmouth,10:53,¬*¬*¬* 23:24
Newhaven, 10:43¬*¬*¬* ,¬*¬*¬* 23:17
Dover, 10:44,¬*¬*¬* 23:09



--
Regards,
Martin Brown
  #4  
Old January 31st 18, 07:03 PM posted to uk.sci.astronomy
N_Cook
external usenet poster
 
Posts: 86
Default Of moon and tides

On 31/01/2018 16:17, Martin Brown wrote:
On 31/01/2018 14:16, N_Cook wrote:
A quirk of celestial mechanics.
As the last blood-red , blue-moon, super-moon was 31 March 1866 we'll
have to wait 55458 days for the next coincidence of the tides in the
channel , presumably.
I wonder what conjuction of tidal harmonics gives a 55,458 day repeat.


It is double the named "Short Callipic Cycle" 2I+S = 75.9y 27729.22d

27729.22 x 2 = 55458.44 but according to the catalogue is unnamed.

I = Inex ~29y and S = Saros ~18y

They are the fundamental periodicities that allow you to catalogue
eclipse cycles. It will be interesting to see if the strong tides this
year drive any climatic effects from deep ocean mixing.

http://www.staff.science.uu.nl/~gent...ipsecycles.htm

Inex gives you an eclipse about the same longitude but opposite latitude
and 3x Saros gives you about the same eclipse conditions in about the
same place on the Earth. Or for an overviews and better explanation

https://eclipse.gsfc.nasa.gov/SEsaro...riodicity.html

The high tides in ports of a large part of the English channel today
are all the same time. I originally thought there was a problem with
big-data
http://www.ntslf.org/storm-surges/la...ast?port=Dover
http://www.ntslf.org/storm-surges/la...?port=Newhaven
http://www.ntslf.org/storm-surges/la...ort=Portsmouth

And from the UK Hydrographic office, high tide times today
Portsmouth,10:53, 23:24
Newhaven, 10:43 , 23:17
Dover, 10:44, 23:09




Ta for that, I'll let the local NOC academic oceanographers know, to
avoid too much head-scratching.
Next stop Milankovitch cycles
  #5  
Old January 31st 18, 09:29 PM posted to uk.sci.astronomy
Martin Brown[_3_]
external usenet poster
 
Posts: 174
Default Of moon and tides

On 31/01/2018 18:03, N_Cook wrote:
On 31/01/2018 16:17, Martin Brown wrote:
On 31/01/2018 14:16, N_Cook wrote:
A quirk of celestial mechanics.
As the last blood-red , blue-moon, super-moon was 31 March 1866 we'll
have to wait 55458 days for the next coincidence of the tides in the
channel , presumably.
I wonder what conjuction of tidal harmonics gives a 55,458 day repeat.


It is double the named "Short Callipic Cycle" 2I+S = 75.9y 27729.22d

27729.22 x 2 = 55458.44 but according to the catalogue is unnamed.

I = Inex ~29y and S = Saros ~18y

They are the fundamental periodicities that allow you to catalogue
eclipse cycles. It will be interesting to see if the strong tides this
year drive any climatic effects from deep ocean mixing.

http://www.staff.science.uu.nl/~gent...ipsecycles.htm

Inex gives you an eclipse about the same longitude but opposite latitude
and 3x Saros gives you about the same eclipse conditions in about the
same place on the Earth. Or for an overviews and better explanation

https://eclipse.gsfc.nasa.gov/SEsaro...riodicity.html


Ta for that, I'll let the local NOC academic oceanographers know, to
avoid too much head-scratching.
¬*Next stop Milankovitch cycles


Checking there was also a nice juicy total lunar eclipse in 1942 Mar 3
which is midway between the one you quoted and now (ie every 2I+S).

https://en.wikipedia.org/wiki/March_1942_lunar_eclipse

Any interesting tides observed back then?

The one later in the year promises to have better UK visibility but we
still won't see totality well - moon will rise in eclipse for the UK:

https://www.space.com/33786-lunar-eclipse-guide.html

Some of these empirical eclipse rules have been known since Babylonian
times! Predicting solar eclipses was a blood sport in the early days of
colonising China when Ferdinand Verbiest nearly got killed before
inflicting that fate on the indigenous lazy court "astronomers".

https://en.wikipedia.org/wiki/Ferdin...onomy_contests

Enjoy! Sometimes truth is stranger than fiction.

--
Regards,
Martin Brown
  #6  
Old February 1st 18, 09:45 AM posted to uk.sci.astronomy
N_Cook
external usenet poster
 
Posts: 86
Default Of moon and tides

On 31/01/2018 20:29, Martin Brown wrote:
On 31/01/2018 18:03, N_Cook wrote:
On 31/01/2018 16:17, Martin Brown wrote:
On 31/01/2018 14:16, N_Cook wrote:
A quirk of celestial mechanics.
As the last blood-red , blue-moon, super-moon was 31 March 1866 we'll
have to wait 55458 days for the next coincidence of the tides in the
channel , presumably.
I wonder what conjuction of tidal harmonics gives a 55,458 day repeat.

It is double the named "Short Callipic Cycle" 2I+S = 75.9y 27729.22d

27729.22 x 2 = 55458.44 but according to the catalogue is unnamed.

I = Inex ~29y and S = Saros ~18y

They are the fundamental periodicities that allow you to catalogue
eclipse cycles. It will be interesting to see if the strong tides this
year drive any climatic effects from deep ocean mixing.

http://www.staff.science.uu.nl/~gent...ipsecycles.htm

Inex gives you an eclipse about the same longitude but opposite latitude
and 3x Saros gives you about the same eclipse conditions in about the
same place on the Earth. Or for an overviews and better explanation

https://eclipse.gsfc.nasa.gov/SEsaro...riodicity.html


Ta for that, I'll let the local NOC academic oceanographers know, to
avoid too much head-scratching.
Next stop Milankovitch cycles


Checking there was also a nice juicy total lunar eclipse in 1942 Mar 3
which is midway between the one you quoted and now (ie every 2I+S).

https://en.wikipedia.org/wiki/March_1942_lunar_eclipse

Any interesting tides observed back then?

The one later in the year promises to have better UK visibility but we
still won't see totality well - moon will rise in eclipse for the UK:

https://www.space.com/33786-lunar-eclipse-guide.html

Some of these empirical eclipse rules have been known since Babylonian
times! Predicting solar eclipses was a blood sport in the early days of
colonising China when Ferdinand Verbiest nearly got killed before
inflicting that fate on the indigenous lazy court "astronomers".

https://en.wikipedia.org/wiki/Ferdin...onomy_contests

Enjoy! Sometimes truth is stranger than fiction.


I doubt anything noticed 1942, any more than generally this week.
Its only the heights that are generally noticed and they are perfectly
normal spring tides this week and this year.
As part of local marine flooding potential, I daily look at NTSLF surge
plots for Pompey, Newlyn and Dover.
Superimposed on the plots is the high tide times ,only, not low tides,
graphically. So it was obvious to the resolution of the plots the times
were the same, highly odd and seemingly in error, Newhaven showed the
same times.
Normally, springs and neaps, the tide pulse goes west to east about 6
hours Newlyn too Pompey and 6 hours Pompey to Dover, where it just about
coincides with the tide pulse down the east coast.

  #7  
Old February 4th 18, 10:50 AM posted to uk.sci.astronomy
N_Cook
external usenet poster
 
Posts: 86
Default Of moon and tides

On 01/02/2018 08:45, N_Cook wrote:
On 31/01/2018 20:29, Martin Brown wrote:
On 31/01/2018 18:03, N_Cook wrote:
On 31/01/2018 16:17, Martin Brown wrote:
On 31/01/2018 14:16, N_Cook wrote:
A quirk of celestial mechanics.
As the last blood-red , blue-moon, super-moon was 31 March 1866 we'll
have to wait 55458 days for the next coincidence of the tides in the
channel , presumably.
I wonder what conjuction of tidal harmonics gives a 55,458 day repeat.

It is double the named "Short Callipic Cycle" 2I+S = 75.9y 27729.22d

27729.22 x 2 = 55458.44 but according to the catalogue is unnamed.

I = Inex ~29y and S = Saros ~18y

They are the fundamental periodicities that allow you to catalogue
eclipse cycles. It will be interesting to see if the strong tides this
year drive any climatic effects from deep ocean mixing.

http://www.staff.science.uu.nl/~gent...ipsecycles.htm

Inex gives you an eclipse about the same longitude but opposite
latitude
and 3x Saros gives you about the same eclipse conditions in about the
same place on the Earth. Or for an overviews and better explanation

https://eclipse.gsfc.nasa.gov/SEsaro...riodicity.html


Ta for that, I'll let the local NOC academic oceanographers know, to
avoid too much head-scratching.
Next stop Milankovitch cycles


Checking there was also a nice juicy total lunar eclipse in 1942 Mar 3
which is midway between the one you quoted and now (ie every 2I+S).

https://en.wikipedia.org/wiki/March_1942_lunar_eclipse

Any interesting tides observed back then?

The one later in the year promises to have better UK visibility but we
still won't see totality well - moon will rise in eclipse for the UK:

https://www.space.com/33786-lunar-eclipse-guide.html

Some of these empirical eclipse rules have been known since Babylonian
times! Predicting solar eclipses was a blood sport in the early days of
colonising China when Ferdinand Verbiest nearly got killed before
inflicting that fate on the indigenous lazy court "astronomers".

https://en.wikipedia.org/wiki/Ferdin...onomy_contests

Enjoy! Sometimes truth is stranger than fiction.


I doubt anything noticed 1942, any more than generally this week.
Its only the heights that are generally noticed and they are perfectly
normal spring tides this week and this year.
As part of local marine flooding potential, I daily look at NTSLF surge
plots for Pompey, Newlyn and Dover.
Superimposed on the plots is the high tide times ,only, not low tides,
graphically. So it was obvious to the resolution of the plots the times
were the same, highly odd and seemingly in error, Newhaven showed the
same times.
Normally, springs and neaps, the tide pulse goes west to east about 6
hours Newlyn too Pompey and 6 hours Pompey to Dover, where it just about
coincides with the tide pulse down the east coast.


From one of the NOC experts on deep-sea oceanography
"I would be very surprised if the tides have any significant effect on
deep ocean mixing."
"tides" in this context referring the recent anomolous tides as
exemplified at Dover last week
  #8  
Old February 5th 18, 10:01 AM posted to uk.sci.astronomy
Martin Brown[_3_]
external usenet poster
 
Posts: 174
Default Of moon and tides

On 04/02/2018 09:50, N_Cook wrote:
On 01/02/2018 08:45, N_Cook wrote:
On 31/01/2018 20:29, Martin Brown wrote:
On 31/01/2018 18:03, N_Cook wrote:
On 31/01/2018 16:17, Martin Brown wrote:

I = Inex ~29y and S = Saros ~18y

They are the fundamental periodicities that allow you to catalogue
eclipse cycles. It will be interesting to see if the strong tides this
year drive any climatic effects from deep ocean mixing.

http://www.staff.science.uu.nl/~gent...ipsecycles.htm

Inex gives you an eclipse about the same longitude but opposite
latitude
and 3x Saros gives you about the same eclipse conditions in about the
same place on the Earth. Or for an overviews and better explanation

https://eclipse.gsfc.nasa.gov/SEsaro...riodicity.html

Ta for that, I'll let the local NOC academic oceanographers know, to
avoid too much head-scratching.
¬* Next stop Milankovitch cycles

Checking there was also a nice juicy total lunar eclipse in 1942 Mar 3
which is midway between the one you quoted and now (ie every 2I+S).

https://en.wikipedia.org/wiki/March_1942_lunar_eclipse

Any interesting tides observed back then?


[snip]

From one of the NOC experts on deep-sea oceanography
"I would be very surprised if the tides have any significant effect on
deep ocean mixing."
"tides" in this context referring the recent anomolous tides as
exemplified at Dover last week


I know it is out of fashion at the moment but I think the Keeling tides
paper PNAS 1997 August, 94 (16) 8321-8328 was actually onto something
(although some of the analysis is flawed and the MEM spectrum (fig 4) is
over fitted causing peak splitting of the 18y Saros peak to 15y & 21y.

They see a strong peak at 58y (2x Inex but fail to comment on it).

http://www.pnas.org/content/94/16/8321

My contention is that there is evidence in their analysis despite them
having removed a fair amount of the longer periodicities for tidal
forcing at 2xInex = 58 years. HADCRUT also shows periodic positive
excursions around 2000, 1940 and 1880 separated by about the Inex
period. You would also expect something at ~54 years which is a period
for about the same eclipse at about the same longitude and especially
when the eclipse is at or near perigee.

My email address is valid so if you would be kind enough to your NOC
expert to get in touch I would be interested to discuss with them why
they would dismiss the possibility of tidal forcing out of hand.

--
Regards,
Martin Brown
  #9  
Old February 5th 18, 12:52 PM posted to uk.sci.astronomy
Andy Walker[_3_]
external usenet poster
 
Posts: 2
Default Of moon and tides

On 31/01/18 14:16, N_Cook wrote:
A quirk of celestial mechanics.

[...]
The high tides [...].


Nothing directly to do with this [interesting] discussion,
but the BBC's programme on the supermoon was trying to explain what
was meant by full/new/quarter Moon, why some were "super", etc.,
the usual stuff. In the middle of which they told us that when the
Moon was new, its pull reinforced that of the Sun, and we had higher
tides than usual. Nothing said directly, but any normal listener
would have inferred that when it was full, and its pull was opposed
to that of the Sun, tides would be lower. I've heard physicists,
who really should know better, say exactly that on TV.

In trying to explain this to people, they can usually accept
that we get "spring" tides when the Moon-tide and the Sun-tide are
reinforcing each other, and "neap" tides when they oppose. The hard
part is explaining why the Moon-tide bulges both towards and away
from the Moon. You can explain till you're blue in the face that the
Moon's gravity pull is stronger on the side of Earth facing the Moon
and weaker on the side facing away, so the water piles up [a little!]
on both sides, but somehow that gets confused with ellipses with the
Earth at one focus, and/or with the phase of the Moon.

I had one former colleague, a highly intelligent and competent
pure mathematician, who came to me regularly to explain this. "We
did this last year!" "Yes, but I've forgotten, and the children have
asked again, and anyway [famous name] was on TV and his explanation
was different. Surely we get lower high tides at full Moon?" "No,
because [blah]." "No, you've lost me. Are you saying that [name]
was wrong?" "Yes. Let's try again ...."

--
Andy Walker,
Nottingham.
  #10  
Old February 5th 18, 03:44 PM posted to uk.sci.astronomy
N_Cook
external usenet poster
 
Posts: 86
Default Of moon and tides

On 05/02/2018 09:01, Martin Brown wrote:
On 04/02/2018 09:50, N_Cook wrote:
On 01/02/2018 08:45, N_Cook wrote:
On 31/01/2018 20:29, Martin Brown wrote:
On 31/01/2018 18:03, N_Cook wrote:
On 31/01/2018 16:17, Martin Brown wrote:

I = Inex ~29y and S = Saros ~18y

They are the fundamental periodicities that allow you to catalogue
eclipse cycles. It will be interesting to see if the strong tides
this
year drive any climatic effects from deep ocean mixing.

http://www.staff.science.uu.nl/~gent...ipsecycles.htm

Inex gives you an eclipse about the same longitude but opposite
latitude
and 3x Saros gives you about the same eclipse conditions in about the
same place on the Earth. Or for an overviews and better explanation

https://eclipse.gsfc.nasa.gov/SEsaro...riodicity.html

Ta for that, I'll let the local NOC academic oceanographers know, to
avoid too much head-scratching.
Next stop Milankovitch cycles

Checking there was also a nice juicy total lunar eclipse in 1942 Mar 3
which is midway between the one you quoted and now (ie every 2I+S).

https://en.wikipedia.org/wiki/March_1942_lunar_eclipse

Any interesting tides observed back then?


[snip]

From one of the NOC experts on deep-sea oceanography
"I would be very surprised if the tides have any significant effect on
deep ocean mixing."
"tides" in this context referring the recent anomolous tides as
exemplified at Dover last week


I know it is out of fashion at the moment but I think the Keeling tides
paper PNAS 1997 August, 94 (16) 8321-8328 was actually onto something
(although some of the analysis is flawed and the MEM spectrum (fig 4) is
over fitted causing peak splitting of the 18y Saros peak to 15y & 21y.

They see a strong peak at 58y (2x Inex but fail to comment on it).

http://www.pnas.org/content/94/16/8321

My contention is that there is evidence in their analysis despite them
having removed a fair amount of the longer periodicities for tidal
forcing at 2xInex = 58 years. HADCRUT also shows periodic positive
excursions around 2000, 1940 and 1880 separated by about the Inex
period. You would also expect something at ~54 years which is a period
for about the same eclipse at about the same longitude and especially
when the eclipse is at or near perigee.

My email address is valid so if you would be kind enough to your NOC
expert to get in touch I would be interested to discuss with them why
they would dismiss the possibility of tidal forcing out of hand.


I'll tell him of your recent post and "newspam"@... em address, remove
both " ?

My interest is a bit more parochial.
I wonder if the "sotonisation" of the pompey tides
https://www.admiralty.co.uk/Admiralt...20stan ds.pdf
and multiple high-waters for Soton also since the end of 2015,
(correspondence with Southampton Hydrographic office confirming this
phenomenom but no insight as to cause, from them)
change in Lymington tide times, growth of a spit at Pagham Harbour are
all connected.
Perhaps connected to whatever tidal harmonic constituents are close to
syncing together for 2 or more years , along with the super-blue-blood
moon, and all these local effects might drop out again after 2 more years.

Myself and 3 proper NOC oceanographers are intrigued about this local
effect, so far tentatively "blamed" on dredging for aggregates in the
English channel, but an astronomic cause is much more interesting.

 




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