In the words of the Starks, winter is coming—and it's going to be bad. Using a new model to forecast the sun's activity, scientists predict solar activity will fall by 60% in the 2030s to conditions not seen since a "mini ice age" in 1645. For almost two centuries, scientists have known that the sun's activity changes on a 10- to 12-year cycle. Each cycle is slightly different, and predicting the sun's activity has proven difficult thanks to a dynamo caused by fluid deep within the sun. However, after reviewing magnetic field activity over three solar cycles, researchers say they've found a second dynamo close to the sun's surface. "They both have a frequency of approximately 11 years, although this frequency is slightly different," researcher Valentina Zharkova explains. The new model based on the pair has allowed for "unprecedentedly accurate predictions," per Science Daily. As if to crush all hope of warmth, Zharkova notes they're 97% accurate.
That doesn't mean we're all going to freeze solid. Zharkova explains that, according to the "double dynamo" theory, two sets of magnetic waves, "originating in two different layers in the sun's interior," sway between the sun's Northern and Southern hemispheres. When they are "in phase ... we have strong solar activity." But when the "two waves exactly mirror each other, peaking at the same time but in opposite hemispheres of the sun," as is predicted for 2030 to 2040, "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.'" The Maunder minimum, also known as the Little Ice Age, brought significant temperature drops to the Northern Hemisphere from 1645 to 1715, causing England's River Thames to freeze during the winter of 1683-84, reports the Telegraph. Haaretz, which puts the dates at 1300 to 1870, reports some countries suffered crop failure and famine. (The sun is already partly to blame for our shortening spring.)