Signal and variability within a Holocene peat bog — Chronological uncertainties of pollen, macrofossil and fungal proxies

A single raised bog from the eastern Netherlands has been repeatedly analysed and 14C dated over the past few decades. Here we assess the within-site variability of fossil proxy data through comparing the regional pollen, macrofossils and non-pollen palynomorphs of four of these profiles. High-resolution chronologies were obtained using 14C dating and Bayesian age-depth modelling. Where chronologies of profiles overlap, proxy curves are compared between the profiles using greyscale graphs that visualise chronological uncertainties. Even at this small spatial scale, there is considerable variability of the fossil proxy curves. Implications regarding signal (climate) and noise (internal dynamics) of the different types of fossil proxies are discussed. Single cores are of limited value for reconstructing centennial-scale climate change, and only by combining multiple cores and proxies can we obtain a reliable understanding of past environmental change and possible forcing factors (e.g., solar variability).

► Fossil proxies from 4 cores from within the same raised bog site are compared.
► Using independent 14C chronologies, timings of fossil proxy curves are tested.
► We find a considerable degree of individualistic proxy behaviour.
► We discuss implications for signal and noise in fossil proxy records.