Nearly 42,000 years ago, when the Earth’s magnetic fields turned, this triggered major environmental changes, extinct events, and long-term changes in human behavior, a new study reports. The findings, made possible by a new radiocarbon plaque derived from old kauri trees in New Zealand, raise important questions about the microscopic effects of geomagnetic inversion and rotations across the plate. deepest geology, the authors say. “Before this work,” author Chris Turney said in a related video, “we knew a lot of things were happening around the world at 42,000 years ago, but we didn’t know for sure how … For the first time, we were able to find out exactly what happened when the Earth ‘s magnetic fields last moved. “Written in the geological chart there are several situations where magnetic poles moved. planet. Today, an event like this would certainly wreak havoc with today’s electronic and satellite technologies. However, the potential impact of such events is almost unknown. The latest major magnetic movement, Laschamps tour, is a relatively short geomagnetic event that occurred ~ 41,000 years ago, providing one of the best opportunities to study the potential effects of major changes in the Earth’s magnetic field. However, despite strong evidence from a number of paleo-environmental records which show that it coincided with major environmental and ecological changes, the ability to accurately identify this event and its role has been demonstrated. confirmation – if any – of contemporary global changes has been constrained by indefinite radiocarbon calibration for the time being. . In this study, Turney, Alan Cooper and colleagues present a new atmospheric radiocarbon plate with a date derived from the rings of old kauri trees preserved for thousands of years in the wetlands of New Zealand. Like a lost keystone, this new record allowed the authors to better align global radiocarbon records and other ice with the Laschamps. Cooper et al. it marked a significant increase in atmospheric radiocarbon during the period of weakening magnetic field strength before polarity reversal. In shaping the effect of this increase, they found that the geomagnetic field was not at least, when it was estimated that the Earth’s magnetic field was only ~ 6% of the levels. normal, which induced large changes in ozone density in the atmosphere. These trends may have been caused by global climate and environmental changes seen in other climate records that occurred 4242,000 years ago. The finding that geomagnetic field variables can influence global temperature and atmospheric circulation provides a model for understanding irregular and sudden paleo-environmental movements, the authors say.
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