Scientists have observed that (1) the world is warming and the Antarctic ice sheet is melting; (2) the ozone hole would not have expanded without the destructive action of humans
Experts have analyzed satellite imagery and other data to show that (1) if scientific observations are accurate on both counts, the Antarctic ice is not melting; (2) if scientific observations are not accurate on at least one count, there is no global warming and the ozone hole is widening; (3) at least one of the two scientific observations is accurate
Destructive human activity is  existing.