A new study published just last month ties magnetic reversals to mass extinctions.
This is exciting to me, because that’s what I’ve been saying for years in both Not by Fire but by Ice and Magnetic Reversals and Evolutionary Leaps.
The authors maintain that “evolution of life is affected by variations of atmospheric oxygen level and geomagnetic field intensity.’
Entitled “Oxygen escape from the Earth during geomagnetic reversals: Implications to mass extinction,” the new study found that geomagnetic field reversals “substantially” weaken the protection afforded by our atmosphere.
Because our magnetic field weakens during a polarity reversal, the authors propose that more oxygen ions are able to escape our atmosphere, which leads to mass extinctions. As they put it, “accumulated oxygen escape during an interval of increased reversal rate could have led to the catastrophic drop of oxygen level, which is known to be a cause of mass extinction.”
“Oxygen can escape into interplanetary space as ions after gaining momentum from solar wind, but Earth’s strong dipole field reduces the momentum transfer efficiency and the ion outflow rate, except for the time of geomagnetic polarity reversals when the field is significantly weakened in strength and becomes Mars-like in morphology.
The study, by Yong Wei et al., used a simulated oxygen escape rate on Mars to support their hypothesis.
“A geomagnetic reversal could enhance the oxygen escape rate by 3–4 orders,” they found, suggesting a possible “correlation between geomagnetic reversals and mass extinction.”
See entire paper:
(Earth and Planetary Science Letters, 15 May 2014)
Thanks to Skip’py for this link