Paleohydrological changes during the late Holocene are inferred from humification, testate amoebae, and pollen evidence from three blanket peat profiles in northwest Scotland. Replicate peat humification records from the Traligill basin share the same patterns of change for a 600-yr period of overlap between 1800 and 2400 cal yr B.P. The shared patterns, inferred from samples with a resolution of 5–13 yr, represent basinwide hydrological changes. In a nearby, but hydrologically separate, area with caves beneath peat, the luminescence emission wavelength measured in two speleothem samples correlated with the humification record in the overlying peat. This correlation implies that speleothem luminescence emission wavelength depends primarily on decay rates in the soils from which drip waters are derived, as long as there is no major change in soil or vegetation. The peat and speleothem records from the cave site further correlate with the peat records from the Traligill basin. Taken together, the records thus represent a regional climatic signal. Peaks in surface wetness replicated in two or more records occur at ca. 2300, 2090, 2030, 1820, 1600, and 1440 cal yr B.P. Further peaks occur at 800, 570, and 115 cal yr B.P. in the humification and stalagmite records that extend to the present day. Correlative changes have been observed, not only in other peat records from Scotland but also in ice accumulation at GISP2. These further correlations imply that precipitation regimes in Scotland and Greenland were in phase during the late Holocene.

Core B997-328PC is from the landward side of a 100-m-deep basin in Reykjarfjö rdur, a small fjord on the north coast of the northwest peninsula of Iceland. This is an area that can be severely affected by incursions of polar sea-ice but has not suffered marked land erosion during the Settlement period. The core is 422 cm in length and consists principally of finegrained muds with in situ molluscs. Eleven AMS 14 C dates on molluscs indicate a constant sediment accumulation rate of ca. 1 cm 10 yr Ϫ1 for the last 4280 ± 50 yr BP. We measured and derived a variety of proxies for indications of changes in the nearshore environment. These included physical properties and grain size, mass accumulation rates, micropalaeontology (pollen and Foraminifera). Multivariate analysis and constrained clustering were used to define major changes in the proxies. In several parameters the major change in the fjord environment occurred close to 1000 14 C yr ago, thus approximately coincident with the onset of the Settlement of Iceland. Other changes are noted at around 1600 and 3400 14 C yr ago; Betula pollen disappears from the record ca. 1500 yr BP and there are peaks in marine productivity occurring ca. 2 and 3.4 ka. A major decline in carbonate accumulation and a sharp increase in the cold water benthic foraminifer Elphidium excavatum forma clavata 400 yr ago represents the local marine signature of the Little Ice Age. None of the changes in our data can be explained adequately by a simple call to land-use practices and an increase in land to sea transport, but both the pollen and foraminiferal records indicate a decrease and even loss of 'warm' elements in both flora and fauna over the past 4 kyr.

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Abstract. Southern Hemisphere westerly airflow has a significant influence on the ocean-atmosphere system of the mid-to high latitudes with potentially global climate implications. Unfortunately, historic observations only extend back to the late 19th century, limiting our understanding of multi-decadal to centennial change. Here we present a highly resolved (30-year) record of past westerly wind strength from a Falkland Islands peat sequence spanning the last 2600 years. Situated within the core latitude of Southern Hemisphere westerly airflow (the so-called furious fifties), we identify highly variable changes in exotic pollen and charcoal derived from South America which can be used to inform on past westerly air strength. We find a period of high charcoal content between 2000 and 1000 cal. years BP, associated with increased burning in Patagonia, most probably as a result of higher temperatures and stronger westerly airflow. Spectral analysis of the charcoal record identifies a pervasive ca. 250-year periodicity that is coherent with radiocarbon production rates, suggesting that solar variability has a modulating influence on Southern Hemisphere westerly airflow. Our results have important implications for understanding global climate change through the late Holocene.

Analyses of pollen, tephra, mineral input and degree of peat humification from three neighbouring raised peat profiles at Corlea, central Ireland, covering the period of the deposition of a tephra layer dated to just before 2290 cal. BC, and thought to represent Hekla-4 (2310±20 BC), are used to show the problems of relying on data from a single profile when invoking relationships between volcanic activity, climate and ecosys-tem response. While there appears to be a strong correlation between tephra deposition and flooding of the bog surface in one profile, with a short-lived increase in the rate of peat accumulation, comparison with the other two records suggests that peat had already begun a trend to a less humified condition before tephra deposition, and that evidence of local bog surface flooding was neither consistent nor synchronous.