It's actually though by some that the increase in temperature causes elevated levels of CO2, not the other way around. Just an interesting note (at least I though so) to add. Keep up the good work!
Its based in the key of G. He jumps around in the beginning between D C and G. Every now and then he uses F7 (which is actually borrowed from the key of C I think) which sounds weird but cool.
It's actually though by some that the increase in temperature causes elevated levels of CO2, not the other way around. Just an interesting note (at least I though so) to add. Keep up the good work!