It appears that humans are finally beginning to understand how dynamic the geology of the earth is over thousands, ten thousands or even hundred thousands of years.
Apparently, geomagnetic reversals are much more frequent than previously thought and their impact on climate are long lasting (hundreds if not thousands of years) and very dramatic!
Given the still very sketchy knowledge we have about geomagnetic reversals it is possible that we are approaching or entering a phase the next geomagnetic reversal. Scientists so far distinguish between geomagnetic reversals and geomagnetic excursions. "Excursion events typically only last a few thousand to a few tens of thousands of years, and often involve declines in field strength to between 0 and 20% of normal."
The last major geomagnetic reversal happened around 780,000 years ago. The last geomagnetic reversal occurred roughly 42,000 years ago. Scientists have documented about 12 geomagnetic reversals during the last 780,000 years. That translates to a minor geomagnetic reversal event roughly every 65,000 years on average. If you assume for a moment that there were perhaps yet to be discovered minor geomagnetic excursions over that period, then another minor geomagnetic reversal event might be imminent.
"At present, the overall geomagnetic field is becoming weaker; the present strong deterioration corresponds to a 10–15% decline over the last 150 years and has accelerated in the past several years; geomagnetic intensity has declined almost continuously from a maximum 35% above the modern value achieved approximately 2,000 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—10 kilometres (6.2 mi) per year at the beginning of the 20th century, up to 40 kilometres (25 mi) per year in 2003,[23] and since then has only accelerated." (Source)
"Geological archives record multiple reversals of Earth’s magnetic poles, but the global impacts of these events, if any, remain unclear. Uncertain radiocarbon calibration has limited investigation of the potential effects of the last major magnetic inversion, known as the Laschamps Excursion [41 to 42 thousand years ago (ka)]. We use ancient New Zealand kauri trees (Agathis australis) to develop a detailed record of atmospheric radiocarbon levels across the Laschamps Excursion. We precisely characterize the geomagnetic reversal and perform global chemistry-climate modeling and detailed radiocarbon dating of paleoenvironmental records to investigate impacts. We find that geomagnetic field minima ~42 ka, in combination with Grand Solar Minima, caused substantial changes in atmospheric ozone concentration and circulation, driving synchronous global climate shifts that caused major environmental changes, extinction events, and transformations in the archaeological record."
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