Collapsed magnetic field had massive impact on EarthPre 42.000 years, the temporary collapse of the Earth's magnetic field led to mass extinctions and climate change.
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Researchers at the University of South Wales in Australia have shown that the temporary collapse of the Earth's magnetic field has led to extreme climate change. Changes in human behavior as well as mass extinctions over hundreds of years can also be attributed to the event.
Changing the poles is considered a Laschamp event , had led to this collapse. Now researchers know that it was 42.000 years ago and lasted for 800 years. During this period, the Earth was not protected from cosmic rays, which led to thunderstorms, spectacular auroras, increased ultraviolet radiation, and climate changes, among other things.
Ancient tree gives information
Researchers were able to determine the exact timing using an ancient preserved New Zealand kauri tree. The radiocarbon method was used for this purpose. It measures the amount of radioactive C14 atoms in organic material. They provided information on when there was a jump in radiocarbon in the atmosphere. The trees stored these changes in their rings.
The period after the Laschamp event was christened by researchers Adams Transitional Geomagnetic Event or "Adams Event" for short. This is a reference to the author Douglas Adams, who in his novel "The Hitchhiker's Guide to the Galaxy" answered the question about life, the universe and everything with "42". In the original English, the audiobook is narrated by author and actor Stephen Fry, who now also explains the Adams effect for a YouTube video. The look of the video is based on the associated BBC series from 1981.
During the Adams event, Earth's magnetic field still had no more than 6 percent of its original strength, scientist Chris Turney says in a statement. "We basically had no magnetic field at all anymore – our shield against cosmic radiation was gone".
Sun protection and moving into the cave
According to Turney, unfiltered radiation from space caused air particles to ionize in the Earth's atmosphere. Electrons are removed. This ionized air had almost "fried" the ozone layer. Thus provided for climatic changes. These changes can also be read from previous observations. Thus the extinction of the Australian megafauna falls into this period.
People moved into caves due to increased UV radiation
Cave paintings also appear to document the event. Researchers suspect that early humans in different parts of the world sought increased dwellings as a result of the Adams Event. Possibly people sought protection from the increase in ultraviolet radiation. "This could also explain an increased use of red ochre sunscreens," the researchers write. Their paper appeared in the journal Science.
Reducing CO2 emissions
Researchers warn strongly that the next reversal of polarity would have catastrophic consequences. "If a similar event were to occur today, the consequences for modern society would be huge. Cosmic rays would destroy our power grid and satellite networks," explains Alan Cooper, co-author of the study.
There is an urgent need to reduce carbon emissions before there is another reversal of polarity or an extreme change in solar activity. The high levels of carbon in the atmosphere could otherwise lead to an extreme acceleration of climate change.