Dendrochronology and the date of the Thera volcanic eruption

Pierce James Furlong 

The main disciplines that contribute to our understanding of the chronology of the ancient Near East are history, archaeology, and various scientific dating techniques including dendrochronology, radiocarbon dating, and ice-core analysis. Beginning in the 1980s, a major rift began to develop between the historical-archaeological chronology and that based on dendrochronology-calibrated radiocarbon dating. The current disparity between these alternate timelines is probably best seen in two, seemingly irresolvable, debates: 1) the absolute date of the Thera (modern Santorini) volcanic eruption, which is a crucial event in establishing a relative chronology between the historically-dated Near East and the archaeologically-dated Aegean region and, by extension, the wider European continent; and 2) the ‘Conventional’ versus ‘Low’ Chronology dates assigned to Palestinian Iron Age I, a period in Near Eastern history often referred to as the ‘Dark Ages’. I argue that both these disputes arise from incorrectly assembled dendrochronology master sequences, and which underlie the international radiocarbon calibration (IntCal) curve used to convert primary radiocarbon dates (BP) into secondary, calibrated, historical dates (cal. BC). The proposed correction to the IntCal curve will involve a totally new set of correlations between volcanic signals in Greenland ice-cores (GISP2, GRIP and Dye-3), on the one hand, and, on the other, tree-ring growth anomalies (from various regions of the northern hemisphere) that are also seen as resulting from the atmospheric effects of large volcanic eruptions. In support of this change, it will be argued that all scientific research since 2006 that has disassociated the massive GISP2 volcanic signal at 1623 BC from the similar sized signals in the GRIP core at 1636 BC and in the Dye-3 core at 1644/41 BC is built upon a wrong analysis. This hypothesized ‘alternative chronology’ will provide near precise dates for four of the largest volcanic eruptions of the Holocene period, namely, Thera, Aniakchak II, Hekla 3 and Hekla 4, and it will bring much greater chronological clarity to the so-called Hallstatt Plateau.