How do we know humans are heating up the planet? This excellent, easy to understand explanation, demonstrates how climatologists study and analyze global warming. It is not magic, sleight of hand or wishful thinking. Our rapidly warming planet is not due to a "natural" increase. See Global Warming.

The planet reached its hihg
The planet reached its hihg temperature in 1998, it has since been cooling, so you have no arguement, run along treehugging whackjob.