Zharkova models solar sunspot and magnetic activity. Her models have run at a 93% accuracy and her findings suggest a Super Grand Solar Minimum could begin in 2020.
A Super Grand Solar Minimum would have four magnetic fields out of phase. There was about 40-60 years of cold weather 350 years ago. This was a Maunder Minimum of lower solar activity. The historical cold weather had two magnetic fields out of phase.
Zharkova is predicting a cooling effect that is 2.5 to 4 times larger than the Maunder minimum.
So I looked up maunder minimum which led me to Little Ice Age
""" Early European explorers and settlers of North America reported exceptionally severe winters. For example, according to Lamb, Samuel Champlain reported bearing ice along the shores of Lake Superior in June 1608. Both Europeans and indigenous peoples suffered excess mortality in Maine during the winter of 1607–1608, and extreme frost was reported in the Jamestown, Virginia, settlement at the same time.[25] Native Americans formed leagues in response to food shortages.[24] The journal of Pierre de Troyes, Chevalier de Troyes, who led an expedition to James Bay in 1686, recorded that the bay was still littered with so much floating ice that he could hide behind it in his canoe on 1 July.[48] In the winter of 1780, New York Harbor froze, allowing people to walk from Manhattan Island to Staten Island.
The extent of mountain glaciers had been mapped by the late 19th century. In the north and the south temperate zones, Equilibrium Line Altitude (the boundaries separating zones of net accumulation from those of net ablation) were about 100 metres (330 ft) lower than they were in 1975.[49] In Glacier National Park, the last episode of glacier advance came in the late 18th and the early 19th centuries.[50] In Chesapeake Bay, Maryland, large temperature excursions were possibly related to changes in the strength of North Atlantic thermohaline circulation.[51] """
The above comes right after https://en.wikipedia.org/wiki/Little_Ice_Age#Depictions_of_winter_in_European_painting
I'm putting up a high tunnel in my garden this Spring. Good timing