The recent Financial Times article Welcome to the World of the Polycrisis introduces the concept of the polycrisis. Key quote:
A problem becomes a crisis when it challenges our ability to cope and thus threatens our identity. In the polycrisis, the shocks are disparate, but they interact so that the whole is even more overwhelming than the sum of the parts.
The article is written by the noted economic historian Adam Tooze. His earlier article Defining Polycrisis - from crisis pictures to the crisis matrix includes the rather complex polycrisis chart below (click to enlarge).
It highlights seven crises and a wide variety of sub-crises and how they are linked.

The combination of multiple individual crises, coupled with these crises amplifying each other, leads to a polycrisis.
Not everyone agrees that the polycrisis is a new thing.
Quartz's The Case Against Polycrisis points out that throughout history, the world has had many problems simultaneously.
But it's hard to argue with former US Treasury secretary Lawrence Summers who is quoted in the Financial Times article:
"This is the most complex, disparate, and cross-cutting set of challenges I can remember in the 40 years that I have been paying attention to such things."
While on the topic of crisis, the Washington Post's Asteroids! Solar Storms! Nukes! Climate Calamity! Killer Robots! covers doomsday scenarios.
These are even worse than the polycrisis in that doomsday scenarios would likely lead to the extinction of humans.
The article has a list of the top 10 doomsday scenarios:
10. Solar storm or gamma-ray burst.
9. Supervolcano eruption.
8. Asteroid impact.
7. Naturally emergent or maliciously engineered, pandemic plant pathogen affecting staple crops.
6. Naturally emergent or maliciously engineered pandemic human pathogen.
5. Orwellian dystopia. Totalitarianism. Endless war paraded as peace. The human spirit crushed. Not a world you'd want to live in.
4. Cascading technological failures due to cyberattacks, reckless development of artificial intelligence and/or some other example of complex systems failing in complex ways.
3. Nuclear war (may jump soon to No. 1).
2. Environmental catastrophe from climate change and other desecrations of the natural world.
1. Threat X. The unknown unknown. Something dreadful but not even imagined. The creature that lives under the bed.
Since we're forecasters, we don't worry about doomsday scenarios in our work. If one were to happen, we'd be out of business.
But the polycrisis - whether new or not - is something we deal with daily.
And we agree with Larry Summers. This is the most complex set of issues and problems we've seen in our decades of doing forecasts.