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How does Solar Max affect the Earth's magnetosphere?
Electromagnetic radiation from the flares arrives at Earth
in about eight minutes and can cause severe disruptions in
the Earth's upper atmosphere, where the radiation is absorbed.
It takes about 70 hours for the CME particles and its associated
magnetic shock wave to arrive at Earth.
In periods of intense solar activity, CMEs can compress the
Earth's magnetosphere. CMEs that travel faster than the low-speed
solar wind produce leading shock waves and force energetic
protons (H+) into the Earth's radiation belt where
they remain for weeks or months following the passage of the
shock front through the magnetosphere. Others work their way
back out into the magnetosheath and are lost to space.
A small number of charged solar wind particles reach the
Earth's atmosphere. If these particles strike gaseous atoms
and molecules in the Earth's atmosphere, they excite them.
When the atoms and molecules "de-excite", they emit bright
colored light at high altitudes. We call this phenomenon the
auroras, or the Northern and Southern Lights. This is one
of the visible effects of the Solar Max on the Earth's atmosphere.
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CME shock
waves compress the Earth's magnetosphere like it is
a balloon. |
In 1997, a CME produced an enormous magnetic cloud and an
interplanetary shock wave that hit the Earth's magnetosphere
on January 10, shortly after midnight, Universal Time. The
shock was followed about 24 hours later by some unusually
high-density solar wind—150 particles/cm3,
approximately 15 times the average solar wind density—that
greatly compressed the magnetosphere. This strong pressure
pulse was followed by a solar wind stream traveling at approximately
600 km/s, which is higher than average speed. There was also
a rapid buildup of energetic electrons inside the Earth's
inner magnetosphere that disrupted electrical power grids.
Solar-related atmospheric disturbances can disrupt long range,
short-wave radio communications because these short waves
bounce off the bottom of the ionosphere as they are propagated
from one point to another. High-frequency radio communications
are also affected by Solar Max activity, especially in polar
regions and high latitudes, because Earth's magnetic lines
are more concentrated closer to the magnetic poles.
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For a more technical description, take a Closer
Look at
The Structured Sun and Solar Max: At the Core of the Matter.
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