As far as Global Warming is concerned, I believe that there is plenty of evidence to conclusively say whether or not humans are substantially involved in planetary warming and predict many of the deleterious effects of said warming. However, I personally have
Insufficient Data
In fact, I don’t think that any single person knows enough to say with certainty anything about AGW, as it is a question uniquely suited to a large network of people pursuing disparate yet parallel lines of investigation. In fact, if anyone were to claim that they knew conclusively that AGW was a myth, I would ask to see how many lifetimes they have spent investigating the problem.
Therefore, I will refer to the scientists on this one, and the vast majority say we should be concerned. So I will be concerned.