Simple. I disagree with the Pope about a matter (Is the Earth warming?) on which the Catholic Church teaches NOTHING.
You disagree with the Pope on matters on which the Catholic Church teaches infallibly.
Oh?
Then try to convince the NON-catholic world that this encyclical; that has just been published; with the FULL approval of the Catholic Church of Rome; that is teaching NOTHING.
No, you rejected the entire encyclical as having nothing to do with Catholic faith, and were shown to be wrong, and which deals with more than Climate Change, but how Catholic faith is to respond to that as well as other societal dangers on which the Catholic church has addressed.
And there was a time that the Catholic church taught nothing ministerially about the sun being the center of the universe, interpretive of Scripture. After it did, even if not infallibly, then it became a matter of obedience. Now it is spoken about Climate Change, but you consider your judgment superior to the pope. And Pius X did not limit obedience to the pope to infallible teaching. No wonder you are called a Protestant. You disagree with the Pope on matters on which the Catholic Church teaches infallibly.
No, it is not simple at all, as in both cases the basis for our disagreement is that of personally examining the evidence for such from our authoritative sources. In so doing we reject as valid teaching the novel premise of ensured magisterial infallibility, as being absent and non-essential in Scripture to provide, discern and preserve faith. You likewise reject certain teachings as being as being valid teaching due to personally examining the evidence for such from your authoritative sources.