Ever since the first caveman was forced to get out of bed early the Sun’s cycles have been of studied with interest. From the timings of our daily lives to the coming of Santa each year the Sun’s timing permeates every part of our lives.
Scientists recently met to discuss the 11 year solar flare cycle. Meeting in New Mexico for the American Astronomical Society – AAS – Solar Physics Conference, 320 scientists gathered to compare notes, share information and generally schmooze about the Sun.
Tuesday – 14.06.2011 – the scientist announced their findings and predictions for the next solar cycle. It looks like jumpers and scarfs are in and speedos are out, solar flare activity between 2013 and 2024 may be almost completely absent. The impact of this sustained level of low solar flare activity is still being debated with effects ranging from another mini ice-age, slight mitigation of global warming to some that expect zero impact on the Earths weather.
After fine tuning the computer models with the solar events of the last couple of years some interesting discoveries were made. There are now a number indicators the scientists can use to base their predictions. Helioseismology studies the Sun’s jet-streams or bands of plasma, the jet-streams last through-out a cycle, slowly moving from the pole to the equator. Looking like bands of color on Jupiter the jet-streams have a direct effect on the location and strength of solar flares. Normally towards the end of a cycle new jet-streams should be forming near the poles of the sun, this process hasn’t been observed so far. Solar magnetism is another important indicator, it has been showing a steady decline in the field strength. All of these indicators have led to the prediction that Cycle 25 will have the lowest level of solar flare activity since the Maunder Minimum, a 70 year period with extremely low numbers of solar flare activity.
Solar Minimum as the name suggests is the lowest point of the part of the solar flare cycle with much reduced or no solar flares at all. The Maunder Minimum was an exceptional solar minimum known for its extremely low flare frequency over an extended time, occurring in 1645 to 1715. Sunspots became so rare during the Maunder Minimum that years would pass with no flares. Even the maximum part of the cycle showed very little activity, 150 solar flares happen in an average maximum year. During this period maximum years were averaging 20 solar flares. For 7 cycles the maximum’s went missing.
The Carrigton Event sometimes called Solar Superstorm was a recent example of what an extreme solar flare can do, the most powerful solar storm in recorded history. When the flare reached the Earth telegraph line sparked, pipelines shot bolts of lightning and the Aurora were seen as far south as Rome and the Caribbean. Luckily in 1859 the world wasn’t reliant on electricity so the effects of this storm were more of amazement rather than disaster. Ice cores are used to measure historic solar flare activity, they store the high-energy proton radiation produced by flares.According to studies of these records events of this magnitude occur every 500 years.
The mini ice-age occurred during the Maunder Minimum, this was an extended winter that saw temperatures drop around the world. In 1607 the Themes river froze through allowing people to ice-skate across town. Glacier growth accelerated during this period and for a time it was possible to ice skate on the New York harbor allowing skaters and walkers to cross from Manhattan to Staten Island. There is much discussion amongst the scientific community regarding the connection between the two, did the Maunder Minimum cause the mini ice-age ? Common sense may say they are indeed connected but there is still much to learn about the Earth and Suns relationship and processes before a clear connection can be made.
The scientist have packed up their pencil holders and calculators, the conference has come to a close. With all of the announcements made its time to watch and wait. The solar flare cycle ebbs and flows through its minimum and maximum, with predictions always bring part gamble its time to roll the dice.
For more information at Sky and Telescope, press release, NASA, SolarHam
Buddha’s Brother out…
