February 8, 2011
There is good physical evidence that the magnetic poles of the Earth have inverted from time to time. It seems to be around every 300,000 years or so but it appears that it has been over 700,000 years since there has been a magnetic pole reversal recently. To avoid confusion we must note that there are multiple poles of the Earth. There are the geographic North and South poles which are marked as 90 degrees North latitude and 90 degrees South latitude where all the meridians of longitude intersect at the rotational axis of the earth like on a desk top globe at the bottom and top.
The rotational axis of the Earth is tipped at about 23 degrees from the plane of the planets in the solar system and this axial tilt is what gives rise to our seasons as the sun revolves around the sun in a year. The Earth spinning on its axis makes it relatively stable like a gyroscope and it has been pointing toward the star Polaris for a long time. In fact there is just a little bit of wobble, like a top or gyroscope has, because of asymmetries in the Earth’s shape. This is called precession and involves a change of about 1 degree in wobble in the angulation of the earth’s axis per 100 years. Astrology, the parent of Astronomy, was tied to associating predictive value to the constellations that surround the equator at certain times. This precession of the equinoxes has recently created a 13th house of the zodiac.
The other two poles are the North and South magnetic poles. The geographic poles are relatively stable. These magnetic poles on the other hand may move around 50 miles or more in a day. The magnetic poles are what a conventional compass seeks. As you approach a magnetic pole, the compass points more and more down toward the Earth. At the exact magnetic pole, the magnetic lines are perpendicular to the surface of the Earth and at the North pole, the north needle will point straight down and south needle straight up. At the South pole, the opposite situation is true. The North magnetic pole is a long way from the North geographic pole. In fact it is above the US and Canada about even with the northern extreme of Alaska latitude wise. 82.7 degrees North and 114.7 degrees West. The South magnetic pole is even more asymmetric. It is not even on Antarctica. It is 64.5 degrees South (remember south geographic pole is 90 degrees South) and 37.7 degrees EAST. That is south of Australia. That means the axis of the magnetic poles is already at a whopping angle. Starting in the West, going under Canada and North America, crossing through the center of the Earth behind Africa and coming out in the East between Australia and Antarctica. The speed of the surface of the Earth at the equator (zero degrees latitude) is a little over 1000 miles per hour. Under the crust of the earth are mysteries including a molten layer that overlies other mysteries. The core is presumed to be mostly iron but there are many other elements including carbon. The CO 2 in our atmosphere originally was boiled out of the molten earth. Diamonds are a form of carbon spewed forth from volcanic vents. A lot of deep oil is probably non-organic or abiotic (made the same way diamonds are). It is estimated that there are 20,000,000,000,000,000 tons of primal carbon in the earth. The movement of the crust over the molten magma and iron core powered by the rotation of the Earth with variable velocities of 1000mph at the equator and zero at the geographic poles results in powerful electrical currents within the Earth that give rise to the magnetic field. The position of the tectonic plates and continents affect the lines of magnetic force. These lines of magnetic force enter and leave the Earth at the magnetic poles.
Navigation has traditionally been greatly facilitated by the use of the magnetic compass. Geographers and cartographers learned that there is substantial variation between geographic and magnetic North. This is so ubiquitous that formal charts used for navigation have isogonal and agonic lines drawn on them so navigators can make appropriate corrections for magnetic declination or magnetic deviation as it is also known. Agonic lines are lines where geographical and magnetic headings are the same. Isogonal lines are lines where there is variance between geographic headings and magnetic headings. By convention on NOAA government maps, agonic lines are green. The red isogonal lines are separated by two degrees of East deviation and the blue isogonal lines are separated by two degrees of West deviation. Records are available on aviation charts going back 50 years for most of the world that detail what the magnetic deviation is. Claims have been made that the magnetic deviation is changing faster than it ever has before. It is not clear that this is the case, but it may be so. Historical data was reviewed at www.ngdc.noaa.gov/geomag for 1961, 1971, 1981 1991,2001 and 2011 in Leon County Texas.
To reach zero degrees magnetic deviation, a correct geographic and magnetic heading or an agonic reading the drift would need to continue to the West for 217 minutes of longitude which will take 31 years if you assume 7 minutes of longitude change per year. If you average the change and use 5 minutes, it takes 43 years to reach a true heading.
- A d v e r t i s e m e n t
Most things in nature are cyclical and tend to trend up and down. Assuming that the trend to the West continued at an increased rate of 10 minutes longitude per year indefinitely (which I think very unlikely) then tipping the magnetic axis 90 degrees would take 540 years. This would give us time to adjust to new weather patterns.
Predicting the weather is a hard thing to do long term. The Farmer’s Almanac has an algorithm relating to the phases of the moon and has proven surprisingly accurate. Recent study has shown that particles ejected from the sun in solar wind are heavily involved in seeding the atmosphere for cloud and rain formation. The moon tweaks the shape of the magnetic fields surrounding the Earth and so has great influence on how much of the particles from the solar wind get in. Normally our Earth’s magnetic field is roughly perpendicular to the orbital path and thin at the magnetic poles. That is why you see the Aurora Borealis in far northern climes. This is also why the vast majority of solar wind does not come straight on into the atmosphere. In fact the magnetic field shunts a vast majority of the solar wind around the Earth through the Van Allen Radiation Belts. This is why people are so concerned that if the magnetic poles become unstable, wobbly or suddenly reverse, we could be subject to radiation and very extreme and crazy weather. The above projection indicates that a shift would more likely be slow and take a thousand years for a full reversal.
The more catastrophic thing to contemplate is that if the massive magma flows caused tectonic binding and the whole thing got out of balance like a washing machine with the load unbalanced, we could have a shift in the geographic poles and then humanity would not survive the ride unless we had colonized near space. One nice note, the washing machine rarely unbalances when there is water in the hopper. We still have a lot of water in our machine.