The Atmosphere of Iceland
One of the most fantastic natural phenomenon, the
aurora borealis (also known as the Northern Lights), occur high up in the earth’s
atmosphere. Lucky observers can watch a spectacular light show in the sky, with
vibrant colors seemingly dancing with the stars. The aurora borealis surrounds
the north magnetic pole, and they can be seen in Iceland in September through
March, on clear nights. The auroras are caused by highly charged electrons from
solar wind (“streams” of energy released from the sun) interacting with
elements in the atmosphere. Solar wind streams off of the sun at up to one
million miles per hour, and it takes nearly forty hours for it to reach the
Earth. When they finally do reach our planet, the energy flows along the
magnetic lines of force that surround the Earth, that radiate from it’s core.
As the wind flows through the magnetosphere (which is a highly charged electrical
area), it interacts with two specific elements of the Earth’s atmosphere,
Oxygen and Nitrogen. These interactions
can occur very high in the atmosphere, nearly two hundred miles from the
surface, but they can also start at only twenty miles above the surface. The color that is created by this interaction,
is dependent upon what element the solar wind is hitting, and at what altitude
the interaction is taking place. For several months of the year, you can see
the aurora borealis from the island of Iceland. Iceland uses this amazing optical
phenomenon as a tactic for drawing tourists in to visit the country.
- Green - oxygen, up to 150 miles in altitude
- Red -
oxygen, above 150 miles in altitude
- Blue -
nitrogen, up to 60 miles in altitude
- Purple/violet
- nitrogen, above 60 miles in altitude
Here, in Iceland, we can
see the sun in the sky, along with a green hue of the borealis. This color is
caused by oxygen reactions with solar wind.
Here in Iceland, we can
see a snow covered area, and an amazing mix of all of the aurora colors: green,
blue, purple, and red.
Resources:
