Study: Geomagnetic Field Of Earth Not Flipping Within Human Lifetime

Study: Geomagnetic Field Of Earth Not Flipping Within Human Lifetime - The Earth’s magnetic field won’t flip within our lifetime, a new research announces.

Scientists reveal in a scientific article published in Proceedings of the National Academy of Sciences this week that the geomagnetic field of Earth may be getting weaker, but it’s not yet below the long-term average.
Paleomagnetism expert Dennis Kent, one of the authors of the research, says the Earth’s magnetic field may even “go back the other direction” in the next 100 years. 

The Earth’s magnetic field is one of the reasons why you, me and the whole human civilization still exist. Without it, our planet could turn into a barren world like Mars.

About 4.3 billion years ago, Mars had an ocean of water. But NASA said recently in a study that it had lost about 87 percent of its surface water after the Sun’s solar wind stripped its atmosphere which may be about the same size or larger than Earth’s. Apparently, Mars has no inner dynamo that can create a magnetic field - so after billions of years, Earth maintained its surface liquid water, while Mars didn’t and died.

Weakening magnetic field

A study published last year suggested that the Earth’s magnetic field is weakening, and it may be 10 times faster now.

The Earth’s magnetic field deflects the Sun’s harmful solar wind and cosmic rays. When the geomagnetic field is weaker, more radiation gets through, and it will disrupt man-made power grids and other platforms used for communication.

For the new research, scientists say they’ve used a new technique to measure changes in the magnetic field’s strength in the past - and they found that its long-term average intensity over the past 5 million years was only about sixty (60) percent of the geomagnetic field’s strength today.

Scientists say the results of their research fits expectations that the intensity of the Earth’s magnetic field should be twice at the equator.

In contrast, the research adds, the time-averaged intensity calculated from the paleointensity database doesn’t meet the “two-to-one, poles-to-equator dipole hypothesis,” and the database calculation suggests that the long-term average intensity over the past five million years is similar to the field’s intensity today.

Researchers believe the difference is in how the samples were analyzed.

In the new research, scientists used ancient lava flows from sites near the Earth’s equator and compared the paleointensity data with from lavas collected near the planet’s South Pole.

As the lava cools, says researchers, iron-bearing minerals form inside and act like tiny magnets, and they align with the Earth’s geomagnetic field. Scientists can analyze these ancient lavas to determine both the magnetic field’s intensity and direction at the time of the lava’s formation.

The team analyzed multi-domain samples using a new technique, and they worked with a representative range from the past five million years using 27 lavas taken from the Galapagos Islands, about 1 degree of latitude from the equator. Results from the area were then compared to results from 38 lavas with single-domain properties taken near McMurdo Station in Antarctica, about 12 degree of latitude from the South Pole.

The results of their study show that Earth’s time-averaged magnetic field intensity over the past 5 million years is about sixty percent of the field’s intensity today, and their findings align with the geocentric axial dipole hypothesis, or the GAD hypothesis, both in intensity and direction.

Kent says other studies using only single-domain basalt glass from ocean floor have found a similar time-averaged intensity, but they didn’t have samples to test the polar-to-equator ratio. Source: StGist
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