Geomagnetic Reversal
The Earth has a magnetic field that goes for the core of our
Earth well into the surrounding space. This magnetic field
(also referred to as the geomagnetic field) interacts with
tthe solar wind. The solar wind is the charged particles are
are being shot off of the sun. The geomagnetic field
protects the Earth from these charged particles. Since the
magnetic field is an electrical charge it deflects the
charged particles coming from the solar winds.
Image supplied by NASA
The magnetic field flips its polarity many times over the years. These flips are often referred to as the geomagnetic reversal. Typically the reversal happens (roughly) every 200,000 to 300,00 years. The most recent reversal was the Brunhes-Matuyama reversal which was about 780,000 years ago. Based off of the information we have at hand we are overdue for a geomagnetic reversal and it can happen at any point.
One concern about the geomagnetic reversal is that we won't
be protected from the incoming solar winds. NASA states,
"Another doomsday hypothesis about a geomagnetic flip plays
up fears about incoming solar activity. This suggestion
mistakenly assumes that a pole reversal would momentarily
leave Earth without the magnetic field that protects us from
solar flares and coronal mass ejections from the sun. But,
while Earth's magnetic field can indeed weaken and
strengthen over time, there is no indication that it has
ever disappeared completely."
So while the field wont disappear completely, it could
certainly get weaker during a potential geomangetic
reversal. A weaker field could lead to increase in solar
radiation reaching Earth. This increase in solar radiation
reaching Earth could potentially damage our electronics just
as electronics on spacecrat are impacted by solar particles.
While this is all speculation, as we haven't seen a magnetic
reversal during a period which we've had electronics as we
do today, there doesn't seem to be a major concern of our
electronics being destroyed during this event. As NASA
stated, this "doomsday hypothesis" is not very plausible,
but it does have some truth behind it.