An interesting question would be, how much heat do all of the world datacenters produce and how much energy would it take to raise the average temperature of the Ocean by 1 degree?
The world generates 20,000 TWh of electricity per year, and maybe 10% is for IT. That's 7.2e18 joules of electricity / year in IT.
So it would take 780,000 years to heat by 1 C. Or 780 years to heat by 0.001 C.
Other sources of global warming are far, far worse.