Dating Thera

8 Mar 2012

Various attempts to equate the low growth tree ring event of 1628-5BC with the Thera volcano are not supported by acidity peaks in ice cores. Whereas Mike Baillie sought to show a 40 year error/difference between tree ring dates and those of ice cores there are in fact a number of acidity peaks in GISP2, at 1669, 1623, 1602, 1600, 1594, and 1577BC. These are best described as originating in volcanoes - but only those eruptions with a sulphur content. The low growth tree ring event, on the other hand, reflects a sharp drop in temperature - and this may not have a connection with volcanoes (we don't know). The information on the above acidity peaks in GISP2 comes from an article published by Antiquity in Sept 1997, by Buckland, Dogmore and Edwards (available via