I've been trying to envision a scenario where global warming is accelerated to the fasted possible speed.
One scenario I thought of was detonating large scale nuclear warheads on the North and South Poles, as well as Greenland.
Russia claims to have missiles, the RS-28 Sarmat (a.k.a. the Satan 2), capable of destroying Texas, France or the U.K. in one hit:
Russian media report that the missile will weigh up to 10 tons with the capacity to carry up to 10 tons of nuclear cargo. With that type of payload, it could deliver a blast some 2,000 times more powerful than the bombs dropped on Hiroshima and Nagasaki.
How much faster (in general) would global warming proceed if:
One missile hit dead center on the ice of the North & South Poles, as well as Greenland
Or, an alternative scenario is the missles are placed down inside the ice caps, either halfway down inside the ice, or at the base of the ice, where it meets land (where applicable)
Note: the goal is to melt all the ice on Earth as quickly as possible, so some alterating of the above parameters is acceptable.