Print

The sun takes a rare hiatus

The sun takes a rare hiatus
5 (100%) 1 vote

Sunspot activity may be entering a lull for the first time in almost 400 years, offering scientists a rare chance to gauge how solar conditions affect Earth’s climate. “This is highly unusual and unexpected” says Frank Hill, a researcher at the National Solar Observatory. Three new NSO studies suggest that the sun’s fluctuating magnetic field may soon become too weak to produce sunspots, those dark regions of gas on the solar surface that normally wax and wane every 11 years. The sun should reach the peak of that cycle next year, but its recent calm “weather” including slower surface wind patterns and fewer solar flares could signal it’s entering a period of relative dormancy. That would mean less solar radiation reaching the Earth.

The last time sunspots disappeared, in 1645, their absence lasted for 70 years, during which Earth experienced a frigid period known as the “Little Ice Age.” Hill says there’s not “enough evidence either way” to say whether that dip in the sun’s magnetic activity caused the Earth’s cooling. But he says the coming sunspot hiatus will be “a splendid opportunity” to figure out how the sun’s weather affects our climate.

 

 

Solar activity is declining—what to expect?

Is Earth slowly heading for a new ice age? Looking at the decreasing number of sunspots, it may seem that we are entering a nearly spotless solar cycle which could result in lower temperatures for decades. "The solar cycle is starting to decline. Now we have less active regions visible on the sun's disk," Yaireska M. Collado-Vega, a space weather forecaster at NASA's Goddard Space Flight Center

But does it really mean a colder climate for our planet in the near future? In 1645, the so-called Maunder Minimum period started, when there were almost no sunspots. It lasted for 70 years and coincided with the well-known "Little Ice Age", when Europe and North America experienced lower-than-average temperatures. However, the theory that decreased solar activity caused the climate change is still controversial as no convincing evidence has been shown to prove this correlation.

Helen Popova, a Lomonosov Moscow State University researcher predicts that if the existing theories about the impact of solar activity on the climate are true, then this minimum will lead to a significant cooling, similar to the one during the Maunder Minimum period. She recently developed a unique physical-mathematical model of the evolution of the magnetic activity of the sun and used it to gain the patterns of occurrence of global minima of solar activity and gave them a physical interpretation.


http://phys.org/news/2015-08-solar-decliningwhat.html