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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