Note here that he is talking about the technical aspects of scientific matters (e.g. What is the best treatment for lung cancer? What is the most efficient way of producing ethanol? etc.) and not the moral aspects of scientific matters (e.g. Is in vitro fertilization permissible?). The latter is certainly within the Church's area of competence and it can and should pronounce on it, whereas the former is not.
Thus, a statement such as "Increased use of air conditioners is causing global warming" would be a technical issue and beyond the Church's competence to evaluate.
I remember Dr. Kevorkian talking about how poisoning people was “a MEDICAL issue, not a LEGAL issue.”
And people bought it.
I was waiting for the day that a butcher cut up his wife, USING THE TOOLS OF HIS TRADE, and when arrested, said, “This is a BUTCHERING issue, not a LEGAL issue.”