Is the ocean broken?

Discussion in 'All Things Boats & Boating' started by daiquiri, Oct 24, 2013.

  1. Will Gilmore
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    Will Gilmore Senior Member

    As far as I know, there is only one magnetic pole, but I admit that that has just been an assumption on my part.
    I N quotes "poles" plural, which leads me to believe he was referring to the axial poles.
    It has been known that the Earth's axis has a wobble. But since the axial poles are the standard by which a true compass bearing is based, as Yob noted, all movement from there is South or North, depending on which we are referencing.

    If the geographic pole wanders, does that mean a new axis? Yet, wouldn't that also bring True North right along with it or do we maintain the old geographic North separate from the axial North?
    First I've heard of drifting poles other than the magnetic pole. Last I heard of the drifting magnetic pole was it was moving farther South after having crossed its most Northern position.
    So, True North and Geographical North are not the same. Now I know about three different North Poles. Very confusing. I'm glad there are only two represented on the charts.

    -Will
     
  2. hoytedow
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    hoytedow Fly on the Wall - Miss ddt yet?

  3. ImaginaryNumber
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    ImaginaryNumber Imaginary Member

    Actually, there are two magnetic poles ... sort of!!!! See below.
    I am using the term "geographical pole" to refer to where the lines of longitude converge. Those two points (north and south) are also suppose to be where the axial poles are, but, as we've found out, the axial poles move some. The geographical poles aren't suppose to move. If they did it would affect the coordinates of every place on Earth. Though thanks to continental drift I guess every place is moving some all the time. I wonder how often they have to update the GPS satellites?
    Looks like there are four poles: geographical, axial, magnetic, geomagnetic.

    North magnetic pole

    [​IMG]

    The north magnetic pole is a point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards (in other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down). There is only one location where this occurs, near (but distinct from) the geographic north pole. The geomagnetic north pole, a related point, is the pole of an ideal dipole model of the Earth's magnetic field that most closely fits the Earth's actual magnetic field.​

    [​IMG]
    The movement of Earth's north magnetic pole across the Canadian Arctic in recent centuries,
    continuing in recent years across the Arctic Ocean towards Siberia
     
  4. goodwilltoall
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    goodwilltoall Senior Member

    20210430_034844.jpg If Earth wobbles, drifts, axis pole shifts, etc.. then why is the North Star- polaris fixed and never ever moved in all recorded history. The sky is an ageless map, all stars maintain constant and precise locations in relation to each other since ancient times.

    The evil Georgia guidestones built in 1980 have a small hole where tonight if you desire, you can look thru and see the North Star same exact location as when when built 40 years ago. Many other similar structures from centuries and even millennia past are evidencing same proof of a stationary, none moving Earth

    Know and accept the Truth or disregard to hold up beliefs
     
    Last edited: Apr 30, 2021
  5. Will Gilmore
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    Will Gilmore Senior Member

    Look up Hypparchus.

    It takes about 25,000 years for the axis to go through a complete cycle.
    upload_2021-4-30_5-17-22.png

    -Will
     
  6. ImaginaryNumber
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    ImaginaryNumber Imaginary Member

    It is also good to think, study, and learn from others before setting your own thoughts in concrete.

    This implies that, until the last few decades, pole movement has been ~0.2mm (~.007")(~two thicknesses of paper) per year. Do you really think that a hole in a rock can detect that sort of motion?

    BTW, Polaris is not at true north, only near true north...at the moment.

    Pole star
    History
    [​IMG]
    The path of the north celestial pole among the stars
    due to the effect of precession, with dates shown

    [​IMG]
    The path of the south Celestial pole among the stars
    due to the effect of precession

    In classical antiquity, Beta Ursae Minoris (Kochab) was closer to the celestial north pole than Alpha Ursae Minoris. While there was no naked-eye star close to the pole, the midpoint between Alpha and Beta Ursae Minoris was reasonably close to the pole, and it appears that the entire constellation of Ursa Minor, in antiquity known as Cynosura (Greek Κυνόσουρα "dog's tail")[1] was used as indicating the northern direction for the purposes of navigation by the Phoenicians.[2] The ancient name of Ursa Minor, anglicized as cynosure, has since itself become a term for "guiding principle" after the constellation's use in navigation.[...]
    Polaris
    [...]The celestial pole will move away from α UMi after the 21st century, passing close by Gamma Cephei by about the 41st century, moving towards Deneb by about the 91st century. The celestial pole was close to Thuban around 2750 BC,[22] and during classical antiquity it was slightly closer to Kochab (β UMi) than to Polaris, although still about 10° from either star.[23] It was about the same angular distance from β UMi as to α UMi by the end of late antiquity. The Greek navigator Pytheas in ca. 320 BC described the celestial pole as devoid of stars. However, as one of the brighter stars close to the celestial pole, Polaris was used for navigation at least from late antiquity, and described as ἀεί φανής (aei phanēs) "always visible" by Stobaeus (5th century), and it could reasonably be described as stella polaris from about the High Middle Ages. On his first trans-Atlantic voyage in 1492, Christopher Columbus had to correct for the "circle described by the pole star about the pole".[24] In Shakespeare's play Julius Caesar, written around 1599, Caesar describes himself as being "as constant as the northern star", though in Caesar's time there was no constant northern star.[...]
     
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  7. goodwilltoall
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    goodwilltoall Senior Member

    20210430_075747.jpg Keep disregarding what is actual proof as you see every night w your own eyes, feeling no crazy speeds, and then try to comprehend the illogical helio theory to believe a fairy tale

    "Belief is the enemy of knowing"
     
    Last edited: Apr 30, 2021
  8. ImaginaryNumber
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    ImaginaryNumber Imaginary Member

    Speed at which world’s glaciers are melting has doubled in 20 years
    • On average glaciers lost 4% of their volume over 20 years
    • Between 2000 and 2019, they lost 267 gigatonnes (Gt) of ice per year, equivalent to 21% of sea-level rise
    • This was 47% higher than the melting ice sheet in Greenland and more than twice that from the ice sheet in Antarctica
    • As a cause of sea-level rise, glacier loss was second only to thermal expansion
    • The study uses historical Nasa satellite data going back 20 years and covering 99.9% of the world’s glaciers
    The lead author, Romain Hugonnet, of the University of Toulouse, said the data was an urgent warning. “A doubling of the thinning rates in 20 years for glaciers outside Greenland and Antarctica tells us we need to change the way we live. We need to act now,” he said. “It can be difficult to get the public to understand why glaciers are important because they seem so remote, but they affect many things in the global water cycle including regional hydrology, and by changing too rapidly, can lead to the alteration or collapse of downstream ecosystems.”

    The paper was published in Nature
     
  9. goodwilltoall
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    goodwilltoall Senior Member

    People can publish n say what they want but we see the same weather patterns in our life year after year. Yes, there were great cataclysms in past times which ALL cultures recorded (much more accurate historical accounts than modern day expositors of the religion of Scienctism rewriting history to fit their beliefs). Mankind has very little effect regarding weather however, the technocracy practicing pseudoscience will pull at any straws
     
    Last edited: Apr 30, 2021
  10. Will Gilmore
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    Will Gilmore Senior Member

    Very nice write up.

    +1 but... can one really know?

    And one must resist indoctrination? How does one pass on a sense of values to the next generation?

    Do you fly? Does it feel like 500 knots is faster that 50 mph in your car? It's force we feel, not speed, and only when it is uneven across our bodies. That's why we exprienced gravity, but don't really feel it when we fall, until we stop.

    -Will
     
  11. goodwilltoall
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    goodwilltoall Senior Member

    20210430_111131.jpg After hundreds of years trying to prove gravity it's still only a theory, never seen, quantified, or experimentally duplicated Density n buoyancy are know n quantifiable equations with electrostatic electricity/magnetism explaining n PROVING things like water clinging to a window.

    Only in an enclosed system can you isolate variables, trying staying outside your car at 50mph, now a plane at 500mph, or the sr-71 at 2100mph (which was designed to expand 8" in flight) but the ISS supposedly going 17,000mph can do space walks, let alone believing the earth traveling 2.2 million mph thru space and still holding on to its gases while existing in the most powerful vacuum imaginable
     
    Last edited: Apr 30, 2021
  12. Yobarnacle
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    Yobarnacle Senior Member holding true course

    Inside the cover of the NauticalAlmanac are the corrections for latitude by Polaris. Part of the table is a correction that varies by the month. However, all the corrections combined are tiny. For small boat navigation such as yachts, getting an accurate sextant sight is difficult and usually has more human error than the table corrects for, so you may assume the altitude of Polaris read directly on your sextant equals your latitude, in a practical sense. The Vikings sailed the north Atlantic with cruder calculations.
    [​IMG]
     
  13. ImaginaryNumber
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    ImaginaryNumber Imaginary Member

    Human behavior must be factored into climate change analyses
    • When temperatures rise among inland fisher households in Cambodia people fish less often
    • At the same time stocks of fish and other aquatic foods also rise with temperatures, leading to slightly larger catches
    • It would appear that overall fish catches appear unchanged annually, when in fact, more nuanced dynamics are at play
    • This study highlights why it’s necessary, when studying changing environmental conditions, to include human behavior along with ecosystem responses
    This research was published in the journal Science Advances
     
  14. hoytedow
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    hoytedow Fly on the Wall - Miss ddt yet?

    The problem is not human behavior; it's human misbehavior.
     

  15. ImaginaryNumber
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    ImaginaryNumber Imaginary Member

    We are certainly keeping our eye on you! <laugh>
     
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