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Sunspots and Climate Change
Almost every day, with the right equipment, you can see large,
dark patches that cover parts of the sun's surface. These dark
patches are called sunspots. They are slightly cooler patches of
the surface of the sun that expand and contract as they move. It
may not seem important to understand sunspots, but they can
have a huge effect on our current climate, as well as the future of
our world.
History of the Sun Spot
Sunspots have been recognized as early as 28 B.C. when
Chinese astronomers noticed small, dark areas of the sun.
Unfortunately, because of a thick religious overtone of astronomy
at the time and a lack of proper equipment to look directly at the
sun, no one knew why exactly the sun had spots. Astronomers
were able to look at the sun and see the spots with their naked
eyes, but even on cloudy or hazy days when this was possible, it
was still quite dangerous and people risked permanent
blindness. Eventually, the Dutch, in 1608, invented the
telescope, which allowed astronomers to finally get a good look
at sunspots up close. However, it was not until the 20th century
that enough technology existed to be able to truly discover the
mystery of the sunspot.
What is a Sunspot?
Sunspots turned out to be areas of cooler zones on the surface
of the sun. These spots are about one-third cooler than the rest
of the surface and are protected by magnetic fields that stop the
heat from being transmitted into the zone. The magnetic field is
formed from underneath the sun's surface, but is able to project
itself outside through the surface and all the way to the corona of
the sun.
How Sunspots Reach Our Climate
The sun has the largest effect on the climate that we enjoy on
Earth. Without it there would be no light, resulting in no growth,
since our climate largely relies on the sun to provide the energy
needed for photosynthesis. Sunspots were first noticed to affect
the Earth when scientists realized that increased activity with
sunspots creates increased interference with magnetic
instruments on the surface of the earth.
As scientists looked further into this phenomenon, they noticed
that near the sunspot, hotter areas of the sun would react with
the magnetic field outside the sunspot and create a solar flare.
Solar flares project a host of things, including x-rays and energy
particles rushing toward the Earth's atmosphere in the form of a
geomagnetic storm.
How Sunspots Affect Our Climate
The first most noticeable effect of sunspots on our climate were
the northern and southern lights, otherwise known as the aurora.
With sunspots come an increase in ultraviolet rays that emit from
the outer ring of the sunspots toward Earth. This increase in UV
rays affects chemistry of the outer atmosphere and the energy
balance of Earth. The idea that sunspots affect Earth's climate is
still largely debated, but it is believed that the increase of
sunspots on the surface of the sun can reduce the amount of
energy and light distributed to Earth. This decrease in energy
can result in colder weather and even "mini ice ages" on parts of
Earth that are farther from the equator.
However, sunspots affect life on Earth through the Borealis and
the Aurora Australis. The magnetic field that is projected from
solar flares is much more powerful than the magnetic field that
protects Earth, which creates a magnetic storm seen by the
colors in the sky during these two events. These magnetic fields
can also disrupt power grids and radio signals on Earth and the
satellites that orbit Earth.
1. Dark patches on the Sun are called ___________________
2. When were sunspots first discovered?
3. Did astronomers find the sunspots with their naked eye or the use
of telescope or both?
4. What is a sunspot?
5. Why does our climate rely on the Sun?
6. Scientists first noticed that sunspots were affecting Earth when
increased activity with sunspots interfered with what?
7. Hotter areas of the sun react with the magnetic field outside
the sunspot and create a ____________ _____________.
8. The first most noticeable effect of sunspots on our climate
were the _________________ and _______________
9. These “lights” are known as the ____________________.
The Aurora lights are solar flares that project a very strong
______________________ field.
How can these solar flares affect Earth and the life we live?
Do sunspots cause the climate to increase (get hotter) or to
decrease (get colder) _______________________.