continuous winter for 18 years - evidence from tree rings show several remarkable aberrations in world climate which took place in the years 535-536 AD. would it have been the cause for the decline of the kalabhras ....far fetched.
The Byzantine historian Procopius recorded of 536, "during this year a most dread portent took place. For the sun gave forth its light without brightnessÂ… and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear."
Tree ring analysis by dendrochronologist Mike Baillie, of the Queen's University of Belfast, shows abnormally little growth in Irish oak in 536 and another sharp drop in 542, after a partial recovery.Similar patterns are recorded in tree rings from Sweden and Finland, in California's Sierra Nevada and in rings from Chilean Fitzroya trees.
Further phenomena reported by a number of independent contemporary sources:
Low temperatures, even snow during the summer Dark clouds, only a few hours of sunlight during the day Summarily, there were reports of almost night-like darkness at midday Floods in formerly dry regions Crop failures It has been conjectured that these changes were due to ashes or dust thrown into the air after the impact of a comet or meteorite, or after the eruption of a volcano (a phenomenon known as "volcanic winter").
The 536 event and ensuing famine has been suggested as an explanation for the fact that Scandinavian elites sacrificed large amounts of gold at the end of the Migration Period, possibly to appease the angry gods and get the sunlight back.
Also, the decline of Teotihuacán, a city in mesoamerica comparable in power to ancient Rome, is correlated with the droughts related to the climate changes, with signs of civil unrest and famines.
The Gaelic Irish Annals[1] record the following - A failure of bread in the year 536 AD - The Annals of Ulster A failure of bread from the years 536-39 AD - The Annals of Inishfallen There was an extraordinary universal plague through the world, which swept away the noblest third part of the human race, 543 AD - The Annals of the Four Masters 1 A great mortality which is called Belefeth, in which Mobhi Clairinech, whose name is Bercan, 'prorectano poetae', perished. 541 AD - Chronicon Scotorum.