-OpEd- SÃO PAULO — The tragedy that has stuck Rio Grande do Sul, Brazil’s southernmost state, is unprecedented. The amount of rain that has fallen in recent days and is still falling there is extreme and so are the consequences. The death toll has reached 100, and more than a hundred people are still missing. More than 1 million people have been affected. For the latest news & views from every corner of the world, Worldcrunch Today is the only truly international newsletter. Sign up here. These impressive figures and the images that look more like disasters caused by hurricanes or tsunamis can…