Climate changes of 535-536In the years 535 and 536, several remarkable changes in world climate took place. The following were reported by a number of independent contemporary sources:
- low temperatures, even snow during the summer
- dark clouds, only few hours of sunlight during the day
- floods in formerly dry regions
- crop failures
In a 1999 book, David Keys, supported by work of the American volcanologist Ken Wohletz, suggested that the Indonesian volcano Krakatau exploded at the time and caused the changes. He further speculated that the climate changes may have contributed to various important developments, such as the emergence of bubonic plague, the migration of Mongolian tribes towards the West, the end of the Persian empire, the rise of Islam and the end of various civilizations in Central and South America. These ideas are not widely accepted at this point.