You don't actually need to be particularly smart to use a scientific approach.
You need little more than an open mind.
We are fortunate in having an enormous data stream on global temperatures and they consistently show consistent increase over decadal periods. I'm through with putting up the graph but you can find them in several of my posts over the past few days.
Our Earth is warming so we can rule your "cooling hypothesis" out.
One prediction from AGW modelling is that we can expect a greater frequency of extreme events. You quite correctly imply there have been many floods in the past but if you look to bb's earlier post you will notice this it isn't just one or two floods but a very large number of them that have impacted on sea levels. In the past we could reasonable expect the occasional flood but now we are getting more of them.
