Some do try to link the event to volcanoes, but if one were to look at the Sulphate index in GISP2 ice core, there is evidence of an erruption occuring around 1157 +/- 2 BC, but the largest climate disruption appears at 1151 BC in the Irish oaks, and with Bristle cone pine frost rings occuring in 1150 +/- 1 BC, during a time when the sulphate signal is indistingusihable from background. It seems strange that a volcano that caused a downturn at 1157 (+/-) should have such a delayed effect a few years later, given that general consensus that volcanic aersols have low residency times in the atmosphere. It would also be odd that given the level of sulphate in teh GISP2 core that it should still effect climate a god 15 years later to 1142 BC when the Irish tree rings recover (see image below).



However, one thing that is not openily advertised is that there is little correlation between GISP2 (american) ice core, and the GRIP (european) ice cores. GRIP would appear to be replicated by three cores, but the issue that appears with this is that they use different time scales in each of the cores, making absolute dating a nightmare (plus the issue of their use of anchor dates as highlighted in Baillies "one story or two paper". So it is difficult for outside observers to ascertain which if any are correct, especially since GISP2 lost large chunks of ice due to surfacing issues when bringin the ice up. Indeed there is debate over which if any of the cores are correct within certain epochs of human history, and there is great anticipation on the data gleaned from the new NEEM ice core to help resolve certain issues. Some argue that because of the replication of the 3 European cores (GRIP, NGRIP and DYE3) that it would be better dated, but some have counter argued that the methodology simply cloned the DYE3 core, and thus any flaws in that are replicated in teh other 2. Also layer counting seems to have been achieved through flow modelling of ice. For GISP2, they appear to have actually counted layers without, and even though they lost ice when it surfaced, anchor dates to historical volcanoes match the chemistry, but some are still not convinced by the fact that large chunks of data are missing, effectively creating sections of floating chronology.

Ice core data is avaiable here [www.ncdc.noaa.gov] for GISP 2 and [www.ncdc.noaa.gov], for GRIP.

It is interesting though that the article is trying to redate the Exodus to such a late date. Such dating would not seem to be consistent with the internal chronology of the Bible, which states taht there were 480 years between the Exodus and the Building of the temple. One thing I find very strange though is that in the Bible during the time of King David we read about a series of cataclysmic events (outlined in 2 Samuel 22: 9-16 and Psalm 18:7-15) regarding fire, great earthquakes, and famine and pestilence. This event according to the internal biblical chronology occurs 470 years from the Exodus in which teh plagues are also rather cataclysmic. Looking to tree ring data we see that there are two climatic downturns in 1628 BC and 1159 BC though 1159 BC is by far more pronounced than the former, meaning 469 years between the two events! A Strange coincidence indeed.

Jonny

The path to good scholarship is paved with imagined patterns. - David M Raup