Life on Earth has always been dependent on the conditions of the Sun, so scientists spend a lot of time studying its activity. A recent announcement from solar scientists suggests that the Sun may soon enter a period of significant reduced activity, possibly causing a mini ice age by 2030 – just 15 years from now.
These predictions were announced at the National Astronomy Meeting in Llandudno, Wales, so it hasn't been possible to evaluate the research yet. However, ProfessorValentina Zharkova from the University of Northumbria who made this announcement claims that the findings come from a computer model of sunspots that has made "unprecedentedly accurate predictions," as reported in The Guardian.
The model has shown to have a 97% accuracy when mapping the past movements of sunspots, using data of solar cycles from 1976 to 2008. And if this reliability continues, then the model also has some alarming predictions for the future: a mini ice age sometime around the 2030s.
To achieve these findings, the scientists mapped the movement of solar fluid that moves in roughly 11-year cycles, which correspond to weather cycles on Earth. Around the year 2022 (labeled cycle 25), a pair of waves will be moving to the Northern and Southern Hemispheres of the Sun, getting slowly out of synch and reducing solar activity – and thus our warm weather.
"In cycle 26, the two waves exactly mirror each other – peaking at the same time but in opposite hemispheres of the Sun. Their interaction will be disruptive, or they will nearly cancel each other. We predict that this will lead to the properties of a 'Maunder minimum'," said Zharkova.
The Maunder minimum was a 70-year period between 1645 and 1715. The Sun produced barely any sunspots and the Earth experienced a mini ice age. Parts of northern Europe and the United States experienced uncharacteristically cold winters. The river Thames, flowing through London, even froze over for seven weeks and was passable by foot. The surface was so stable that residents could even hold 'frost fairs' on the ice.
Sunspots are relatively 'cool' regions on the Sun that appear darker when photographed. They are cooler than the rest of the Sun, but they are still around 4500 K (4200ºC, 7600ºF). They are caused by a concentration of intense, magnetic field from the Sun. This inhibits and redirects the flow of hot matter to that region and makes it darker – what we call a sunspot.
Sunspots last between 1 to 100 days, during which they rotate around the Sun, following the flow of solar fluid. Sunspots go through cycles of intensity and sparsity based on the motion of the fluid cycles. There are two main waves that are slightly offset over time, producing periods of maximum and minimum solar activity.
"Effectively, when the waves are approximately in phase, they can show strong interaction, or resonance, and we have strong solar activity," Zharkova said.
"When they are out of phase, we have solar minimums. When there is full phase separation, we have the conditions last seen during the Maunder minimum, 370 years ago."
Central Image: We generally associate a 'spot' with a small feature. However, this sunspot is 20 times the size of Earth. This one would have been visible to the naked eye - but you should never look at the Sun with unprotected eyes! NASA.
source: http://www.iflscience.com/
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