So you're not counting the tree ring anomolies that occured between the two big ones? No one thinks there's anything to those?
Sorry, no. I was just addressing the events that I think may have a celestial connection. These are believed to be mostly volcano driven events. There were serious consequences (some say 'near extinction' events) at these dates: 3195BC, 2354BC, 1628BC, 1159BC, 540AD and less serious events at 207BC and 44BC.
The 540AD event is the only one that does not have an acid layer (volcano) in the ice core data. (I may be confusing you, and me, by trying to hard to fit the 2200BC Iraqi crater into the picture). I would like to see the Iraqi crater date change to fit the above mentioned 2354BC timeframe.