As seen so far in the blog, the sun's activities cause and contribute to noticeable impacts upon the climate in the Arctic, dominated by the Milankovitch cycles of Eccentricity, Tilt and Precession. Solar activity has more visible and short term effects in the Arctic, however, including the 'Aurora Borealis' or the Northern Lights. Click 'Read More' for videos, links and explanations...
As explained in this video, the lights occur due to excited particles from the solar wind colliding with oxygen and nitrogen molecules in the atmosphere after being guided to the Poles by the earth's magnetic field. These elements release photons of different wavelength when they return to a ground state, and therefore we see the different colours. Common green colours are created by Oxygen and blue or red colours by Nitrogen atoms.
What I didn't know, however, that the occurrence of these phenomena can be predicted, and the results delivered in a form not too dissimilar from the weather forecasts we are familiar with. Here's an example from 31st October 2011 from http://www.gi.alaska.edu/AuroraForecast
These forecasts are possible because of satellites constantly looking at the output from the sun and observing the behaviour of the 'solar wind', the driver of the Aurora. The wind takes around 2-3 days to reach earth, so the latitudes reached by the Aurora and it's intensity can be predicted fairly accurately in this time frame. Longer forecasts rely on knowing the location of increased activity on the surface of the sun and using the known rotational patterns to forecast an increased solar wind received at the Earth's atmosphere. As with any forecast, however, there are large uncertainties and the process is a constant learning curve. Projects are ongoing to figure out the exact process in which the Aurora is created.
I hope this has been a welcome diversion from the environmental science, and that you've found it all at least mildly interesting. If you did, here's some more videos and links for you to enjoy:
http://www.swpc.noaa.gov/pmap/ - Latest aurora extent from satellite data
http://solarscience.msfc.nasa.gov/predict.shtml - Sunspot forecasts from an 11year cycle, predicted to reach the maximum of the current cycle in around 2012/13. Leads to wild 'predictions' such as this which the press go wild over (and most probably misreport).
http://odin.gi.alaska.edu/FAQ/ - Includes 'why does aurora have the shape of curtains?'
http://pixie.spasci.com/DynMod/ - Latest location of the Solar Wind around the atmosphere
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