Stable oxygen isotopes in irish oaks: potential for reconstructing local and regional climate

The long Irish oak tree-ring chronology, developed for archaeological dating and radiocarbon calibration, is the longest of any in northwest maritime Europe, spanning most of the Holocene (7,272 years). Unfortunately, the rings widths do not carry a strong climate signal and the record hasnever been satisfactorily applied for dendroclimatic reconstruction. This pilot study explores the potential for extracting a climate signal from Irish oaks by comparing the stable oxygen isotopes ratios from 10 oak tree cores (Quercus robur and Quercus petraea L.) collected across the Armagh region of NE Ireland with local and regional climatic and stable isotopic data. Statistically significant correlations between isotope ratios and the amount of summer precipitation (r = -0.44) point to the isotopic composition of summer rainfall as the dominant signal. Including the Armagh data into an extended regional oxygen isotope series did not reduce the correlation coefficient with regional precipitation (r = -0.68, p < 0.01). Correlations of this magnitude in dendro-hydroclimatology are typically restricted to trees growing at their ecological limits. This research suggests that there is considerable potential for including living trees and ancient timbers from Ireland into a regional composite to reconstruct the summer hydroclimate of Britain and Ireland.

L'Europe et les partis politiques nationaux: Les lecons d'un

European integration remains a 'non-cleavage' in relation to the Lipset-Rokkan model, as it has not produced significant restructurings of national party systems. Yet, while not effecting the terms of interparty competition, Europe has nevertheless come to occupy an increasingly large place in national political debates. Since the early 1990s, Euroscepticisms have taken root, to varying degrees, across the entire continent. This article analyses the rise of these Eurosceptic tendencies, examining the phenomenon in terms of both the Europeanisation of national political life and the wider emergence of forms of protest politics. The analysis demonstrates how European questions have been absorbed into established party structures, while at the same time pointing towards a renewed research agenda which pays greater attention both to the discursive dimension of political life and to the roles played by national parties as European actors.