Droughts and floods and so on can be kept track of using primitive methods e.g. put a stick up to where the water went to and write a year on it. Usable histor

Droughts and floods and so on can be kept track of using primitive methods e.g. put a stick up to where the water went to and write a year on it. Usable historical temperature records go back to the 1700s or so IIRC - it's not very precise but you can still use the data.