I don't think that has an impact, it is in the same class as, with all those people, will we get out of orbit, like gravity out of control, or when we all jump at the same time.

The cattle 'cows, sheep, chicken' that 8 billion people need is a bigger issue of co² emission than all our cars, so the biggest part of this is because Mc Donalds needs millions of cows a year for their hamburgers, the emission from farting (cows fart) are 10 times higher than all industry (factories, cars) combined.