Hmmm, came across a forwarded mail warning about the impending doomsday, end of the world etc etc....the world's gonna end by 2012 it announced. Usually, i delete all this stuff from my inbox, but today i desisted. Had nothing better to do, so decided to go thru it, wasn't much long anyway.
"The world will end in 2012, say experts" went the subject line...it had all myriad kinds of doomsday theories ranging from scientific to religious, stupid to the macabre...the one which caught my eye was regarding swapping of earth's poles....
So I ended up googling up the stuff, and wound up with some interesting findings. The claim it seems isn't half as false as the other theories in the mail. I got references to this in websites of NASA, some educational instutions, other blogs and more doomsday prophets...
At present, the overall geomagnetic field is becoming weaker at a rate which would, if it continues, cause the dipole field to temporarily collapse by 3000-4000 AD. The "South Atlantic Anomaly" (localized field reversal) is believed by some to be a product of this. The present strong deterioration corresponds to a 10-15% decline over the last 150 years and has accelerated in the past several years; however, geomagnetic intensity has declined almost continuously from a maximum 35% above the modern value achieved approximately 2000 years ago. The rate of decrease and the current strength are within the normal range of variation, as shown by the record of past magnetic fields recorded in rocks.The Earth's magnetic north pole is drifting from northern Canada towards Siberia with a presently accelerating rate. It is also unknown if this drift will continue to accelerate.
Glatzmaier and collaborator Paul Roberts of UCLA have made a numerical model of the electromagnetic, fluid dynamical processes of Earth's interior, and computed it on a Cray super-computer. The results reproduced key features of the magnetic field over more than 40,000 years of simulated time. To top it off, the computer-generated field reversed itself.
- Its unknown whether this field decay will continue further.
- Some speculate that a greatly diminished magnetic field during a reversal period will expose the surface of the earth to a substantial and potentially damaging increase in cosmic radiation. However, homo erectus and their ancestors certainly survived many previous reversals.
- There is no uncontested evidence that a magnetic field reversal has ever caused any biological extinctions.
- A possible explanation is that the solar wind may induce a sufficient magnetic field in the Earth's ionosphere to shield energetic particles even in the absence of the Earth's normal magnetic field.
- Present society with its reliance of electricity and electromagnetic effects (e.g. radio, satellite communications) may be vulnerable to technological diruptions in the event of a full field reversal.
- Natural Phenomenon like the aurora borealis, bird migrations etc. may vanish..
pretty heavy stuff huh???...
so till l8r...