Probably one of the most contrived sports I have seen, top fuel drag racing has to be high on the list of top environmentally polluting sports too - from both a greenhouse gas and NOISE point of view!!
This is a 5.8Litre, supercharged V8 top fuel dragster running on nitromethane, and it produces a gargantuan 7500 Horsepower. This particular car did a 1/4mile in 5.128 seconds and probably burned 50-75 litres of fuel in the process. That's alot of carbon dioxide sent into the atmosphere to cover such a short distance (certainly more CO2 than my car would produce, I use 45 litres of diesel in my car to cover about 500 miles!!!)
http://www.pbase.com/scubamoo/image/60966443