If someone asked you if you believed that God was judging the nation through the floods and storms of recent weeks, what would you say? Would you say no in order to avoid being thought of as a religious fanatic, when in fact you rather think the correct answer is yes. Or would you say no and wonder what that says about your view of the Old Testament in particular?
On the other hand you might well say yes because you see God acting in this way in the Bible and see no reason to deny that he continues to to do the same and that in fact the Bible makes it quite clear that judgment is coming and that will take the form of earthquakes and floods because you remember reading that somewhere or you heard it one Sunday night when someone preached about the end times.
Perhaps I should call my insurance company and ask them how the determine whether something is an "act of God". Then again, maybe we ought to remind ourselves that judgment, whatever form it might or might not take, is God's area of expertise and his prerogative, not ours. You'd think sometimes that we believe that we're best placed to make the call, but that would put us at the very least on an equal footing with God if not slightly ahead of him, and that is surely a dangerous position in which to find ourselves! Is it not enough for us to know that one day God will judge and he will do so righteously. Ours is a simpler task: to live lives that honour God. To love others into the kingdom rather than judge them out of it. Sometimes that's messy, sometimes it looks like we're compromising our faith. Jesus was known as a friend of sinners and it wasn't meant as a complement.
I try not to judge anyone. When I was the minister of a local church, something I did for 20 years, I often seemed to end up asking folk who's found themselves in some situation or another whether they thought their situation and the way they were handling it honoured God or not. Rarely did I ever have to point them to a particular verse or passage that talked about their situation. They knew the Bible well enough to work it out for themselves.
Is that enough? I don't know. And for the record, neither do I know whether the recent storms are a result of global warming to divine displeasure. The former is certainly a factor and as to the latter, I haven't asked and God hasn't told me.