PROXY CLIMATE RECORD FOR THE LAST 1000 YEARS FROM IRISH BLANKET PEAT AND A POSSIBLE LINK TO SOLAR VARIABILITY

Recent research has shown that ombrotrophic mires can yield a proxy cl imate signal based on changes in the degree of peat humification [1,2] , and that oceanic margin sites show the most sensitive record [3]. We compare humification records for the last 1000 yr from two radiocarbo n-dated blanket peat profiles from western Ireland, and show several c orresponding periods of climatic fluctuations. Periods favouring reduc ed peat decomposition, suggestive of wetter and/or cooler climatic con ditions, seem to coincide with periods of reduced sunspot activity and atmospheric C-14 anomalies. Whilst climatologists have continued to d ebate a link between solar variability on a century timescale and clim ate change, the exact nature of that link remains elusive [4-7]. The r esults from Ireland demonstrate that data derived from mires could be relevant to the debate as to the extent of solar forcing in natural cl imatic variability, and the curves shown provide a continuous record t o add to previous evidence for the so-called 'Medieval Optimum' and 'L ittle Ice Age' [8]. The record may imply that, during the past millenn ium, climatic change at the oceanic margin of the northeast Atlantic l argely corresponded to inferred variations in solar output.