Revisiting the longest European paleoenvironmental archive

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Long marine, ice core and terrestrial archives spanning multiple glacial-interglacial cycles provide a unique perspective into the evolution of Quaternary climates. Firstly, they reveal a more complete view of the range of climate variability and associated biotic responses, and secondly, they allow us to observe long-term trends in the character of this variability. Among these archives, Tenaghi Philippon, NE Greece, has continued to occupy a prominent position despite the fact that pollen analyses were initiated as early as the 1960s. This is a function of (i) its temporal length, containing a record of vegetation changes of the last 1.35 million; and (ii) its completeness, as demonstrated by its close correspondence with global deep-sea records. However, the lower part of the record had low sampling resolution and, moreover, the original core is no longer curated. A new high-quality core of the upper 60m was recently obtained by a team led by Prof. J. Pross (Frankfurt), while a further coring campaign to reach a depth of 150m is currently being organized for Autumn 2007. This application seeks to obtain funding to extend the coring in 2007 from 150m to 200m (from about 0.9 to 1.35 million years ago [Ma]), reaching the base of the polleniferous deposits. The new core will be curated in Germany, where whole-core logging and palaeomagnetic analyses will initially be undertaken. This will form the basis of several future research grant proposals in association with German and Dutch colleagues. In the context of the current application, I propose to undertake a high-resolution pollen analysis of an early Pleistocene glacial-interglacial cycle around 0.95 Ma, an interval characterized by 41 thousand year (kyr) climate periodicity. More specifically, by examining the vegetation response within a 41-kyr glacial-interglacial cycle, it may be possible to test whether 'cryptic' precessional (23-kyr) variations in ice volume occurred, as recently suggested by Raymo et al. (2006) who pointed out that because precession is out of phase between hemispheres, changes in ice volume in each hemisphere would cancel out in globally integrated reconstructions of sea level. While the Raymo et al. hypothesis is difficult to test using palaeoceanographic or sea level proxies, changes in local vegetation may retain a memory of hemispheric ice expansion. Thus, if northern ice sheets did expand in the middle of the 41-kyr cycle in response to precession, that should, in principle, be reflected in a contraction of S. European tree populations.