FOX News has a report on the current radiation output, the irradiance, of if our planets primary and almost only source of heat and light.
I do not believe in spoilers, but for background my astrophysists friends tell me there are at least 19 different “solar cycles” that affect irradiance. When they stack up one way, the minimum radiance is virtually the same as the same as the maximum radiance and not much happens.
But approximately every 10,000 years the cycles stack up the wrong way, and there is a really sharp drop in the amount of radiation the Earth receives from its primary of life giving warmth. The last two times that has happened coincide with two “mini ice ages, the “Elder Dryas” and Younger Dryas Stadials.
The two cold periods are named after a genus of flowers native to the shores of tghe Arctic Ocean, whose range during the estimated 1200 to 2200 year duration of the stadials.
Now, very briefly quoting the Michael Guillen bylined report linked above:
The last grand maximum peaked circa 1958, after which the sun has been steadily quieting down. Today, the drop in activity is at its steepest in 9,300 years
Sp click on over and read the whole thing. There will be no surprises for Alley readers, but the report brings almost everything known together in one place.
Because no one who left us a record was around 9,300 years ago, and because exact dating by reading proxies is a chancy business, all I can say is that we are within the window for another “mini ice age.” If any major portion of our race is to survive, we need to assume the worst, and prepare as best we can.
That includes short a race to develop and disseminate short growing that can be planted in June and harvested in early September. And, most importantly, we must get a substantial population in a “safe harbor” off this planet until circumstances show a one planet existence is safe.