The Tyee has published my article A BC Megadrought? We've Had Them Before. While it mostly discusses the local effects of a new "xerothermic" (dry and hot) period, it concludes with a wider look:
We already see the ominous portents of drought elsewhere in the world. From the Red Sea to the Atlantic, sub-Saharan Africa is retreating before the desert and its people are drowning in the Mediterranean trying to reach cool, wet Europe.
A recent scientific study suggests that the Syrian civil war and the rise of the Islamic State was triggered by drought, crop failure and mass migration that destabilized the Assad regime. If so, then more and worse wars could follow.
Outbreaks of infectious diseases anywhere in the world are likely to reach us easily. A report last fall by the Pacific Institute for Climate Solutions warned that "Vector-borne diseases -- those carried by rats, ticks, fleas or mosquitoes -- are most likely to be affected because climate change affects whole systems.... The bacteria responsible for Lyme disease are carried by ticks, and as temperatures warm ticks are moving north."
Meanwhile, an East African mosquito-borne disease, chikungunya, arrived in the Caribbean just over a year ago and has already sickened well over a million people from Florida to Paraguay. It's a cousin of dengue, also called "breakbone fever," which extends around the world.
To get a sense of where we are before the megadrought, visit Worldometers and check the ever-rising numbers for forest loss, CO2 emission, desertification, and use of water and energy.
Even if the xerothermic doesn't return in full force, we are already on the way to the fate of the Maya, the Anasazi, and many other societies destroyed by lack of water. They never knew what hit them. We, at least, will have the consolation of knowing what hit us.