It means there were much less variously dated disasters in fact.
Chronicle dating may vary from 2 to 3 years which is a usual practice.
Aurelian burned the Alexandrian Library in 270, 271, 272 and 273. When a medieval monk misused the scale he gave out 55 versions of "shifts" alone which falsely let the event to be thrown off from 7 to 2112 years in the past. “the military order of Hera” (Herostratus) burnt the Artemis temple in Ephesus, so the difference between this date and the date of Alexandrian lighthouse destruction is 1731 years.
Therefore, Jerusalem was destroyed both in 68 as well as in 70. As you can see, the four possible dates when the Great Library was burnt can reach up to eleven variants.The ancient settlement was not merely burnt - the ground became fritted. This cannot be described in terms of industrial disaster because there were no ways to reach such temperatures in the Bronze Age.Schaeffer gives an explanation of excavations: the similar events were happening in Etruria (now Tuscany), in the Central America, the same wide fire traces stretch from Egypt to India, through Arabia, reaching China at the end.This is no surprise that the Holy Mountain Moriah turned out to be ploughed (supposedly with an outrageous purpose).And it is clear that it was neither ploughed by burnt city defenders in the Temple nor by Roman soldiers who had no idea about either bull or peasant yoke.