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Geomagnetic excursions Interglacial Termination Abrupt Climate Change

  1. Mar 5, 2010 #1
    There are a series of papers that support the assertion that geomagnetic excursions cause Younger Dryas magnitude abrupt climate change events.

    There is a geomagnetic excursion that correlates with the Younger Dryas abrupt climate change and with similar abrupt climate change events.

    Looking at how the geomagnetic field has changed in the past (the frequency of reversals, the change in the periodicity of excursions during the current ice epoch, and the periodicity of the Younger Dryas type abrupt climate events, the following hypothesis can be formed.

    The periodicity of the forcing event that causes the geomagnetic excursion is around 12 kyr. The same forcing event (smaller magnitude) causes geomagnetic jerks which are secular geomagnetic field changes (regions on the planet surface that have stronger normal or reversed polarity in reference to the current geomagnetic field configuration.

    It appears the cyclic event that is forcing the geomagnetic field is external. The field changes are too closely spaced to be due to internal changes in the planet. As the liquid core is conductive rapid field changes in the liquid core induce counter fields in the conductive liquid which inhibits rapid field changes.

    The Paleoclimatic data shows that the Younger Dryas cooling event occurred over 15 years in three 5 years steps. The entire Younger Dryas cooling event was complete in 40 years. The planet cooled from interglacial warm to within 25% of the glacial temperatures. Temperature in the North America cooled by around 18F. What is interesting is the Younger Dryas is one of a series of similar cooling events, including the termination of past interglacial periods.

    During the glacial period the external forcing event has less affect on the geomagnetic field and planetary temperature as the planet is already cold and vast regions of the planet's surface is covered with ice sheets which insulate the planet's surface from the cyclic forcing event, and planetary temperature is already very cold so increased GCR has less effect.

    The affect of the external cyclic event that is forcing the geomagnetic event it appears is dependent on the earth’s axis tilt at the time of the event, timing of perihelion, the eccentricity of the earth’s orbit, the distribution of the continents on the surface of the planet, and the area of the planet’s surface covered by ice sheets.

    http://www.paleomag.net/members/qingsongliu/References/EPSL/Thouveny%20excursions%20since%20400%20ka%20EPSL%202004.pdf [Broken]

    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Mar 6, 2010 #2
    Sorry but this is really apples and oranges.

    Yes, there have been an abnormal amount of geomagnetic excurions in the current Lachamps chron, but it has nothing to do with the Younger Dryas stadial.

    See for instance Guyodo and Valet 1999 which concludes:

    Obviously the Younger Dryas has been associated with a erratic geomagnic reversal, known as the Gothenburg magnetic flip (Morner 1971), but that has only been found in one sediment core in the Botanical garden in Gothenburg. It has never been reproduced, despite vigourous attempts. But there was something wrong with that core. it was broken. Although it has never been officially withdraw, the Gothenburg flip is no longer considered (info oral lecture Prof Cor Langereis).

    Morner, R. A., 1971, Late Weichselian paleomagnetic reversal. Nature Physical Science, vol. 234, no. 52, pp. 173-174 (December 27, 1971).
  4. Mar 6, 2010 #3
    Yohan Guyodo & Jean-Pierre Valet's 1999 work "cold adjusted" the proxy data base that was used to determine geomagnetic field strength. The "cold adjustment" increased the geomagnetic field strength inferred from the ocean floor sediments during periods when the planet was cold which makes it appear the actual change in geomagnetic field strength did not cause the cooling.

    Subsequent geomagnetic field intensity proxy analysis used different proxies to find the "archeomagnetic jerks" which are abrupt secular (regional and hemispheric) changes to the geomagnetic field intensity with a periodicity of roughly 400 years. The secular geomagnetic field changes weakens the geomagnetic field temporarily in a specific region and hemisphere and changes the tilt of the field offsetting it from the rotational axis of the planet. The resultant archeomagnetic jerks is caused by the small version of what is forcing the geomagnetic field.

    There are far too many archeomagnetic jerks and geomagnetic excursions for the forcing function to be due to internal liquid core changes. It appears archeomagnetic jerks, geomagnetic field excursions, and geomagnetic reversals are being forced by a significant cyclic solar event.

    The same solar event is the reason for the anomalous planetary magnetic fields of Uranus and Neptune.

    The Younger Dryas is not a unique event. The termination of past interglacial periods was due to the same solar event that abruptly forces the geomagnetic field. As noted above affect of the solar event on the geomagnetic field is dependent on the tilt of the planet, the timing of perihelion, and the eccentricity of the planet's orbit. The affect is also dependent on whether there is or is not ice sheets on the planet's surface (ice is an insulator) and the position of continents.

    The solar event comes in a small, medium, large, and super large. An event cyclically abruptly changes the geomagnetic field has a significant amount of energy. There are other geological events that are forced by the same cyclic (period of the solar event is not fix but the event occurs again and again) solar event.

    http://sciences.blogs.liberation.fr/home/files/Courtillot07EPSL.pdf [Broken]


    Last edited by a moderator: May 4, 2017
  5. Mar 6, 2010 #4
    Check the graph of planetary temperature change out (figure 1. Increase the magnitude to 150%.) It is difficult for humans living in the current interglacial period to imagine a Younger Dryas type abrupt climate change. It seems physically impossible without a mechanism.

    The city of Chicago was covered with a mile thick ice sheet during the last glacial phase. The city of New York is the center of an ice sheet due to high levels of snowfall on the ice sheet fed by the warm moist air from the Atlantic.

    Current insolation at 65N matches the insolation during the coldest part of the last glacial period. When you look at figure 1, it is obvious that there is some massive cyclic event that forces the planet's climate. Orbital insolation changes are not causing what is observed.

    From an analytical standpoint if one picks incorrect mechanisms (There are at least four paradigm type errors in geological science) the problem becomes impossible to solve. i.e. The method to solve the problem is to look at the anomalies as a group. i.e. If any one fundamental mechanism is incorrect it is not possible to solve the problem or understanding the observations. Look at the data and then develop hypotheses as opposed to starting with a set of mechanisms and then try to adjust the mechanisms to match the observations. i.e. A mechanism has limits. An analogy would be Kelvin's assumption that the source of the sun's energy was gravitational collapse which would limit the age of the earth to thousands of years as opposed to billions of years. An entire set of scientific hypotheses changed when it was accepted that the planet is billions of years old rather than thousands of years old. The point is accepting the observations and following their implications.

    An analogy of the issues that must be addressed to solve this problem is the discovery of tectonic plate motion. Prior to the creation of the tectonic plate hypothesis there were dozens of unexplained anomalies such a matching rare geological formations on the edges of continents that match the same rare geological formation on the adjacent continent, the fact that continental coastlines shapes fit together as pieces of a puzzle and so on.

    The geomagnetic field was assumed to not be capable of rapid changes because it was assumed to be core generated. The geomagnetic liquid core based computer models are 100% theoretical (There is no data on liquid core movements, the models in question are not realistic due to computer limitations. There are unproven theoretical hypotheses.). The recent discovery of very, very, rapid geomagnetic field changes is a paradox. Something that is physically possible with a liquid core field generating mechanism. What should have happened, is geomagnetic science should have raised a flag that there is a paradox.

    The discovery of abrupt climate change and the glacial/interglacial cycle is also a paradox. The climate models that purport to be able to produce a glacial/interglacial cycle do so by creating a model that is unstable, a knife edge model that can theoretically jump. The current data shows the planet resists forcing changes to climate. The recent glacial/interglacial oscillations are a paradox. Abrupt climate, Younger Dryas type climate changes is a paradox. There are no internal changes on the planet that can cause the planet's climate to abruptly change for over a thousand years.

    A very, very, power forcing function is required to abrupt force the geomagnetic field. The same forcing function leaves its mark on the planet causing other geological anomalies such as super volcanoes and kimberlite pipes.

    From Wikipedia:
    http://rsai.geography.ohio-state.edu/courses/G820.01/WI05 climate history/2002PA000791.pdf

    Last edited by a moderator: Apr 24, 2017
  6. Mar 6, 2010 #5
    The discovery that Uranus and Neptune's planetary magnetic field is offset both from the planet's rotational axis and offset from the center of the planet should have been a clue that something is fundamental incorrect with the theory as to what creates a planetary magnetic field. Look at the Uranus and Neptune observations and then think of the cyclic abrupt changes to the geomagnetic field. Add the very recenting finding of a ribbon of gas at the edge of the solar system that is at right angles the planet's orbital plane about the sun. Think of what could abrupt change a planet's magnetic field.

    The solar event exits the sun at the solar equator. This is a very, very, large event and is cyclic. Following the analog of the paradigm shift associated with accepting the planets, sun, stars, and so forth are billions of years old as opposed to 1000's of years old (the point is then one must solve the problem as it is then recognized as unsolved problem), from an astrophysical standpoint what is causing this observation? I have been looking at the astrophysical problem have found a whole set of astronomical anomalies that point to a mechanism. I will start a thread in the astrophysical section as I am starting to make progress.

    The New Solar System, 4th Edition by J. Beatth, C. Peterson, A Chaikin

  7. Mar 6, 2010 #6
    Maybe also consider this quotation of Alfred Wegener:

    Planetary magnetism is only a part of that story. There is a lot more to consider. it should also be considered that even the things that we think we know may be different like for instance the Last Glacial Maximum around 20,000 years ago, with those mile thick ice sheets on America, when the Mammoths roamed the Siberian megafauna steppes; see this post.

    So, before hypothezing all kind of new things, we should really wonder if we cover each and every aspect from the past with that.
  8. Mar 6, 2010 #7
    How problems are solved is as important as the solution. In the case of earth sciences there is curiously sufficient information now to solve the problem. As has happened in the past when people start to discuss the solution suddenly papers will be submitted with the solution.

    The phrase "abrupt climate change" does communicate what has happened in the past. Dangerous, deadly abrupt cooling climate change perhaps would be better. What we have heard concerning warming which cannot occur because the planetary temperature governor regulates temperature is what has happened in the past to explain the glacial/interglacial cycle and the Younger Dryas type abrupt cooling events. The abrupt change to the geomagnetic fields interrupts the planet's climate regulator.

    The abrupt event changes the geomagnetic field first in a secular manner and later over a thousand years of so is integrated by the liquid core to increase or decrease the net geomagnetic field intensity depending on the hemisphere and polarity of the strikes.

    The initial secular geomagnetic field changes will therefore not affect the entire planet in the same manner. It is called secular because regions and one hemisphere is affected more than another. The secular geomagnetic field changes explains why in the middle of a glacial phase specific regions can experience warming.

    What is missing from the discussion is the reality of what has happened in the past and what appears to happening again. The forcing function appears to be a specific solar event that is caused by an interruption of the solar magnetic cycle.

    A cyclic solar event that is capable altering the geomagnetic field will have other affects, in addition to abrupt climate change.

    This paper is interesting. The planet as this paper notes has been cooling for the last few thousand years.

    http://epic.awi.de/Publications/Mac2000c.pdf [Broken]

    Last edited by a moderator: May 4, 2017
  9. Mar 7, 2010 #8


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