It’s the globe trying to correct its self = atmospheric physics

Or to put it another way, every action has a reaction, cause & effect
(NEWTON).

So whilst there isn't a little green man at the centre of the globe
flicking a switch, it's amospheric physics caused by an action in one
area of the globe, and over longer periods of time, having an effect
on another area of the globe, that causes the climate to reach a
tipping point and switch, sometimes very rapidly.

I read somewhere that whilst the effects of the globe warming up may
be gradual, sudden switches to a colder climate and its effects can
happen very suddenly.