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Polar noon (June Solstice)

  • 14-06-2020 9:26am
    #1
    Registered Users Posts: 462 ✭✭ oriel36


    In a week, the North pole will be midway to the planet's circle of illumination for the one and only time this year. Just as every location on the surface is at noon due to daily rotation when it exists midway to the planet's divisor, so too we have a meteorological milestone in tandem with an astronomical one.

    https://www.youtube.com/watch?v=bfEJR2B6w5I

    As the daily rise and fall in temperatures reflect to position of a location to the circle of illumination as the planet rotates once each day, temperatures continue to rise after noon until about 3 PM and fall thereafter.

    Likewise, the annual rise in temperatures for the Northern hemisphere occur after June polar noon until July/August as a reflection of an orbital surface rotation. This feature takes some explaining, however, the effect is the same as the daily temperature fluctuation in terms of location relative to the planet's circle of illumination.

    Meteorology and astronomy are inter-disciplinary even though many would wish to keep them separate. As long as meteorologists split the annual temperature cycle into astronomical and meteorological sub-groupings then the explain for the seasons and even the day/night temperature cycle will be lost.


Comments

  • Registered Users Posts: 462 ✭✭ oriel36


    (Continued)

    It may be the hardest motion to discern for the simple reason that daily rotation swamps it's presence apart from the North and South polar latitudes and it's effects at those latitudes which is governed by a single day/night cycle each year. Within that single day/night cycle is a single sunrise on one equinox and one on the opposite equinox with Polar noon happening this week.

    It can be discerned directly from observing other planets like Uranus where the HST captures both daily rotation and the slower surface rotation arising from the planet's orbital motion (about 50 sec in as the time lapse speeds up) -

    https://www.youtube.com/watch?v=612gSZsplpE

    To account for the change in position of the Earth's North and South poles to the circle of illumination and parallel to the orbital plane which is the orbital component of the seasons requires a simple analogy and experiment.


    If the floor represents the orbital plane of the Earth and the body of a person represents the surface of the Earth, walking/orbiting around a central object adequately explains both the Solstice event and the polar day/night cycle.

    The nose of a person represents the North pole so walking around an object while keeping the nose pointing in the same direction at all times has an astronomical equivalent in the direction of Earth's surface towards Polaris and that area of the galaxy (minus circumpolar motion and any daily rotational input) -

    https://www.youtube.com/watch?v=QwSlkJG8gTU


    Start by walking in the same direction around a central object (representing the Sun) and keeping the nose pointed in the same direction at all times. To maintain the same direction, the experiment demonstrates that the person sometimes has to walk sideways and backwards before facing forwards again thereby their entire body will turn a different side to the central object at one time or another. This is what is happening with Uranus as the planet turns about 4 degrees each Earth year while the Earth turns at a rate of about 1 degree per day.

    The North and South poles act like a beacon for the orbital behaviour of the Earth so while daily rotation is responsible for the 24 hour day/night cycle, the specific of orbital motion is responsible for the Polar day/night cycle including Polar noon in a week, the combination of the two surface rotations creates the hemispherical seasons and related weather events like the hurricane season, Arctic ice evolution and seasonal weather events like heatwaves and winter weather.


  • Registered Users Posts: 2,828 ✭✭✭ Nabber


    Follow the solar equator, this will help understand why some areas remain temperate all year round.
    Seasonal changes are not as distinctive as we see them in Ireland.


  • Registered Users Posts: 462 ✭✭ oriel36


    Nabber wrote: »
    Follow the solar equator, this will help understand why some areas remain temperate all year round.
    Seasonal changes are not as distinctive as we see them in Ireland.

    Following the North and South poles as they change position to the Sun and circle of illumination over the course of a year is far more productive and creative. This change is parallel to the orbital plane of the Earth.

    The myth of the astronomical seasons vs the meteorological seasons is dismissed insofar as the orbital cycle, including polar noon, follows the same principle as the daily noon cycle as temperatures rise after the noon event before slowly declining. In the case of daily rotational noon the rise happens towards 3 PM while the orbital equivalent is towards August so the idea of meteorological seasons is unhelpful in identifying the Earth's motions and cause and effect.

    Polar noon or the June Solstice is when the North pole is midway to the planet's circle of illumination therefore the maximum surface area where the Sun is constantly in view (Arctic circle) is reached before declining over the coming months. This affects such things as hurricane season or Arctic sea ice evolution and should be an enjoyable area of research and inspection.

    https://www.youtube.com/watch?v=xvbV9llG5L8

    The meteorological and temperature fluctuations between either poles thereby influencing large scale seasonal events is a signature of two surface rotations to the Sun as opposed to the deficient notion of a 'tilting' Earth.


  • Registered Users Posts: 462 ✭✭ oriel36


    To appreciate polar noon where the North pole will be half way to the circle of illumination shortly thereby creating the largest surface area where the Sun is constantly in view (Arctic circle), a number of historical and technical adjustments are necessary.

    https://en.wikipedia.org/wiki/Axial_precession#/media/File:Earth_precession.svg

    Copernicus and his contemporaries were tied to the Ptolemaic framework where he was forced into an attempt to mesh his new system of cause and effect between cyclical events experienced on the surface with predictive astronomy which served astronomers since remote antiquity.

    Copernicus correctly identified the change on position of the North pole to the circle of illumination and the central Sun in his original description found in the Commentariolus which was conceived about 30 years before De Revolutionibus -

    "The third is the motion in declination. For, the axis of the daily rotation is not parallel to the Grand Orb's axis, but is inclined [to it at an angle that intercepts] a portion of a circumference, in our time about 23 1/2°. Therefore, while the earth's center always remains in the plane of the ecliptic, that is, in the circumference of a circle of the Grand Orb, the earth's poles rotate, both of them describing small circles about centers [lying on a line that moves] parallel to the Grand Orb's axis. The period of this motion also is a year, but not quite, being nearly equal to the Grand Orb's [revolution]. The Grand Orb's axis, however, being invariant with regard to the firmament, is directed toward what are called the poles of the ecliptic. The poles of the daily rotation would always be fixed in like manner at the same points of the heavens by the motion in declination combined with the Orb's motion, if their periods were exactly equal."
    Copernicus

    http://copernicus.torun.pl/en/archives/astronomical/1/?view=transkrypcja&


    Why the actual behavior of the North and South poles in relation to the Solstice and Equinox points as an annual event was conceptually shifted to a 25,920 year cyclical conclusion is a long and complex story of timekeeping astronomy vs interpretative astronomy and the inability to make the two mesh hence the deficiencies we inherited today in respect to astronomy and meteorology.

    I understand that Copernicus would be crippled with objections had he maintained the correct perspective by his contemporaries whereas today the original proposal needs inspection for its validity. The issue of meteorological seasons vs astronomical seasons is exceptionally unhelpful or what effectively is an attempt to exclude the astronomical components in weather and cyclical seasonal events like the hurricane or Arctic sea ice seasons.


  • Registered Users Posts: 8,201 ✭✭✭ Gaoth Laidir


    I really don't get the message behind this thread.


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  • Registered Users Posts: 462 ✭✭ oriel36


    I really don't get the message behind this thread.

    You can always follow the current hideous 'explanation' of polar noon based on a tilting circle of illumination on a planet with a zero degree inclination -

    https://apod.nasa.gov/apod/ap170319.html

    People have been kind so far in allowing a more suitable explanation of the June Solstice and why the area where the Sun is constantly in view reaches it's maximum circumference known as the Arctic circle and starts contracting after the Solstice event. It also explains why temperatures fluctuate between either poles due to a combination of daily and orbital motion -

    https://www.youtube.com/watch?v=xvbV9llG5L8&t=19s


    Meteorology and the great cyclical events like hurricane and Arctic sea ice season is tied to the astronomical points intimately so creating a meteorological vs astronomical seasons disrupts this appreciation.

    There are many hundreds of points involved but if you believe the NASA 'explanation' for the seasons then you will not get a single one of those points. It is therefore for meteorologists who can move effortlessly between planetary dynamics and weather as an inter-disciplinary necessity.


  • Registered Users Posts: 8,201 ✭✭✭ Gaoth Laidir


    I'm now even more lost. Are you seriously saying that we don't know that the sun is shining 24/7 at the North Pole right now?


  • Registered Users Posts: 462 ✭✭ oriel36


    This is for those who can appreciate that the widest possible circumference, with the North pole at its centre, where the Sun remains constantly in view (Arctic circle) is reached today before that circumference starts to shrink over the next 3 months.

    The North polar latitude changes position of the Sun and circle of illumination as a function of the orbital motion of the Earth so whereas it now exists half way to the circle of illumination today as viewed from the orbital plane -

    https://www.youtube.com/watch?v=bfEJR2B6w5I

    The North pole (where daily rotation is absent) will change position parallel to the orbital plane and will have a position on the circle of illumination on the September Equinox as viewed from the orbital plane -

    https://en.wikipedia.org/wiki/Deep_Space_Climate_Observatory#/media/File:EpicEarth-Globespin-tilt-23.4.gif

    Just as any location (apart from the North and South poles) where the Sun comes into view at dawn and disappears before twilight, noon is when that location is half way to the circle of illumination and temperatures rise well into the afternoon then so with Polar noon and the temperature rises in the Northern hemisphere into July/August.

    When daily rotation and all its effects are subtracted, the entire surface of the Earth still turns once to the Sun as a function of the specific way the Earth orbits the Sun with each individual location experiencing noon and midnight simultaneously through an orbit.

    Daily rotation and its traits swamps the orbital surface rotation, however, two places on the surface of the Earth where daily rotational velocity reduce to zero (North and South poles) act like beacons for the magnificent orbital surface rotation to the Sun.


    The polar day/night cycle and its rotational cause prohibits splitting the seasons into meteorological and astronomical sub-groupings.


  • Registered Users Posts: 8,201 ✭✭✭ Gaoth Laidir


    But what's your point?! Why is every answer an obscure essay? A simple one-liner reply in simple English, please, with no links.


  • Registered Users Posts: 462 ✭✭ oriel36


    But what's your point?.

    From experience of over 30 years dealing with academics, that isn't a question but rather a self-protecting statement signifying that you can't discuss or consider the material. Once again, this is for people who can appreciate polar noon in much the same way as daily rotational noon from a meteorological standpoint rather than presenting the explanation for those who can't.

    https://www.youtube.com/watch?v=bfEJR2B6w5I

    The June Solstice or polar noon is when the North pole is half way to the planet's circle of illumination (line dividing daylight and darkness). It creates a maximum circumference with the North pole at its centre where the Sun remains constantly in view (Arctic circle) before that circumference starts to shrink for the next 3 months until the September Equinox with a single sunset at the North pole on that date -

    https://en.wikipedia.org/wiki/Deep_Space_Climate_Observatory#/media/File:EpicEarth-Globespin-tilt-23.4.gif

    Another view is that on the Solstice, the maximum length of time between sunrise and noon is symmetrical to the length of time from noon to sunset as throughout the year that symmetry is maintained between sunrise/noon/sunset in keeping one rotation in sync with one day/night cycle. Modelers refuse to accept these principles by conjuring up solar days and sidereal days just as the same airheads create meteorological seasons vs astronomical seasons with predictable hideous results -

    " It is a fact not generally known that,owing to the difference between solar and sidereal time,the Earth rotates upon its axis once more often than there are days in the year" NASA /Harvard

    Much like the meteorological vs astronomical seasons, that solar vs sidereal fiction is an impossibility and lacks physical considerations.


    Met Eireann staff should be ashamed of themselves for promoting the recent development of the meteorological seasons for no more than there is a meteorological noon each day vs astronomical noon, neither is there an annual equivalent and exposes how little meteorologists appreciate cause and effect in terms of cyclical temperatures and associated events.


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  • Registered Users Posts: 7,510 ✭✭✭ Doctor Jimbob


    But what's your point?! Why is every answer an obscure essay? A simple one-liner reply in simple English, please, with no links.

    Seems that was too much to ask for.


  • Registered Users Posts: 462 ✭✭ oriel36


    Seems that was too much to ask for.

    Irish people are more or less decent and can easily comprehend that temperatures rise past the Solstice just as they rise past 12 noon until 3 PM or so.

    It is not always possible to reach everyone as perhaps they lack the talent to put the seasonal rise in temperatures in temperatures after polar noon today in terms of sea ice decline, hurricane season or some other topic.

    It is fine to be mean-spirited and dour but that can only get contributors so far as otherwise it is all positive. As the North pole departs its position half way to the circle of illumination after today moves closer then so does the area around the North pole shrinks.

    Beautiful insight for beautiful people if any can be found.


  • Registered Users Posts: 8,201 ✭✭✭ Gaoth Laidir


    Seems that was too much to ask for.

    Wayyyy too much...


  • Registered Users Posts: 462 ✭✭ oriel36


    Wayyyy too much...

    It takes courage to inspect principles that are technically and historically deficient so that people can enjoy a more suitable explanation for the seasons and milestones like polar noon today, not just the astronomical event itself but also the cyclical meteorological events which occur over the next few months as the ocean heats up towards the North pole and links the hurricane season with Arctic sea ice disappearance under a dynamical cause.

    https://www.youtube.com/watch?v=xvbV9llG5L8

    There is no point reading what I present so that is the best I can do for you in one sentence.


  • Registered Users Posts: 2,828 ✭✭✭ Nabber


    Wayyyy too much...

    Rule III Gaoth Laidir, please pay attention you Newtonian heathen :pac::pac:


  • Registered Users Posts: 462 ✭✭ oriel36


    Nabber wrote: »
    Rule III Gaoth Laidir, please pay attention you Newtonian heathen :pac::pac:

    Unfortunately it is more like mob rule here but nothing I haven't seen and dealt with before despite the rudeness involved.

    Whether readers like it or not, the links between cause and effect, astronomy and meteorology or what amounts to the same thing - the motions of the planet and the Earth science of meteorology can't be split apart hence it's inter-disciplinary nature.

    Polar noon today represents not only a milestone in terms of planetary dynamics, it is also a meteorological milestone similar to 12 noon each day as a location exists half way between sunrise and sunset or technically - half way to the circle of illumination.

    Irish people are generally fair and not so small that they can't give time to the links between cause (astronomy) and effects (meteorology).


  • Registered Users Posts: 462 ✭✭ oriel36


    I quite understand the meteorologist perspective which excludes the astronomical component from cyclical weather events but the discipline becomes so much more impoverished on that account. The larger and more expansive perspective prevents modeling based on temperatures/pressure alone and brings in geographical and planetary dynamics which have been excluded for so long.

    It is a different and more productive way of doing things for those who are fair and more willing to push the boat out into astronomy rather than attempting to partition meteorology and astronomy.

    Look at the other planets again with the blue line representing their orbital plane and the relationship of axial inclination to that blue line -

    https://calgary.rasc.ca/images/planet_inclinations.gif

    Jupiter has an inclination of 87 degrees to the orbital plane. If the Earth had that inclination, the seasonal variations in daylight/darkness across all latitudes would be quite small and barely noticeable throughout the year much like areas around the Equator or what effectively are 'no seasons'.

    Uranus has an 8 degree inclination to the orbital plane. If the Earth had that inclination, the seasonal variations in daylight/darkness would be extreme across all latitudes much like those experienced within the Arctic circle presently.

    So, it is possible to model weather conditions across latitudes for all planets within a spectrum of 90 degrees (equatorial) and 0 degrees (polar) based on inclination relative to the orbital plane. The Earth is largely towards the equatorial end of the spectrum with a sizable polar component ( 23 1/2 degrees) using the new format.

    Far more fascinating, creative and productive than the 'tilted' Earth explanation which is rather forced and doesn't account for observations which today can be made up close from the perspective to the orbital plane. The old folks or those who trot out the old 'tilted' explanation might complain but for everyone else it is a 21st century way to look at the seasons from the orbital point of view where the Earth moves and the Sun is stationary and central.


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