Carbon emissions have been increasing every year on earth. This carbon release was increasing before bitcoin was present.
With a car that consumes 1 liter of fuel, 30% of the energy goes to useful work - the car goes forward, while 70% goes to waste heat.
With Bitcoin, for every liter of fuel burned 99.999999999999999999999999% goes to waste heat. Only .0000000000000000000000001% goes to the miner that guessed the correct number and made the next block - which is the 'useful work' being done by mining.
It would be VERY, VERY hard for you to invent a less efficient machine than Bitcoin mining. It is a most spectacularly horrible idea. Well, only horrible for those who like the planet. If your goal is to fuck up the Earth, then Bitcoin mining is your best friend.