Nobody had any clue. There was certainly no warning. It is part of the picture that now suggests a sudden failure in the west-southwest flank of the Anak Krakatau volcano was a significant cause of Saturday's devastating tsunami in the Sunda Strait.
When rice farmers started producing yields nine times larger than normal in the Malian desert near the famed town of Timbuktu a decade ago, a passerby could have mistaken the crop for another desert mirage.
Every year more than a million people are victims of domestic abuse in the UK. Often the focus is on helping the victim find safety — but what of the abusers? Should they be given help? And can they change?