2012 Geomagnetic Reversal of the PolesAnother theory proposed by the 2012 phenomenon is that there will be a geomagnetic reversal on December 21, 2012, which could cause a severe disruption in technology. Doomsday theorists claim that this event could possibly leave the Earth vulnerable to extreme doses of solar radiation. Their theory is supported by evidence that the Earth's magnetic field is weakening, indicating a possible reversal, and predictions for an unusually high solar maximum by NASA scientists in 2011 and 2012. Scientists do claim that Earth is overdue for a reversal of its magnetic field as the last reversal is believed to have been 780,000 years ago. They also claim however, that a reversal could take up to 5,000 years to complete. NASA has said that high solar maximums occur every 11 years and the event is not unusual.
Criticisms of the 2012 PhenomenonDespite these various theories and their spread through various forms of media and communication, there are criticisms- the strongest of which have come from Mayan scholars. These scientists claim that any "Mayan Prophecies" should be read very carefully mainly because the artifacts from their history are fragmentary and the whole picture is unknown. They also say that many of the prophecies are contradictory and combine ideas from the Maya, Aztec and Mixtec- all of which had different calendars and end dates for those calendars.
Scholars also claim that the history of the Maya may have been manipulated either by their own leaders, other civilizations such as the Aztec or Spanish colonists. Finally, critics of the 2012 phenomenon as it applies to the Maya say that there is no mention of destruction or the end of civilization on 18.104.22.168.0 and there are implications that life and their calendar would continue after the end date.
To learn more about the Maya and the 2012 Phenomenon, visit About.com's Archaeology site featuring a section on Mayan Civilization and the Foundation for the Advancement of Mesoamerican Studies.