Investigating the Interhemisphere 14C Offset in the 1st Millennium AD and Assessment of Laboratory Bias and Calibration Errors

Past measurements of the radiocarbon interhemispheric offset have been restricted to relatively young samples because of a lack of older dendrochronologically secure Southern Hemisphere tree-ring chronologies. The Southern Hemisphere calibration data set SHCal04 earlier than AD 950 utilizes a variable interhemispheric offset derived from measured 2nd millennium AD Southern Hemisphere/Northern Hemisphere sample pairs with the assumption of stable Holocene ocean/ atmosphere interactions. This study extends the range of measured interhemispheric offset values with 20 decadal New Zealand kauri and Irish oak sample pairs from 3 selected time intervals in the 1st millennium AD and is part of a larger program to obtain high-precision Southern Hemisphere 14C data continuously back to 200 BC. We found an average interhemispheric offset of 35 ± 6 yr, which although consistent with previously published 2nd millennium AD measurements, is lower than the offset of 55–58 yr utilized in SHCal04. We concur with McCormac et al. (2008) that the IntCal04 measurement for AD 775 may indeed be slightly too old but also suggest the McCormac results appear excessively young for the interval AD 755–785. In addition, we raise the issue of laboratory bias and calibration errors, and encourage all laboratories to check their consistency with appropriate calibration curves and invest more effort into improving the accuracy of those curves.

Women in Ulster, 1600-1800

Some have entertained the belief that early modern Gaelic society conferred substantial rights on women. This could hardly be farther from the truth. In aristocratic Gaelic circles women were used ruthlessly as pawns in political alliances and other manoeuvres. The status of women at the lower levels of society also seems to have been low relative to men. While patriarchal relationships persisted after the Plantation of Ulster, they took new forms. Some women actually benefited in terms of property rights relative to men. Economic change in the eighteenth century, in particular the development of proto-industry, opened up opportunities for poorer women but it is notable that women did not feature at all in the public political sphere before 1800