ABSTRACT
The conventional view of the Pleistocene, until a few years ago, was that there had been four great glacial periods separated by warmer interglacials and broken by interstadials, the whole lasting for the million years of the Quaternary era. The last major glaciation, ending with the withdrawal of the Wurm-Weichsel-Wisconsin ice sheets, was succeeded by a period of gradually rising temperatures during the Post-Glacial, to reach an ‘optimum’ followed by a ‘deterioration’. The Little Ice Age of the last few centuries, which it seemed could be regarded as the culmination of this deterioration, was succeeded by a warming in the early decades of this century. The Boreal, Atlantic, sub-Boreal and sub-Atlantic sequence was illuminated and refined by palaeobotanists using pollen analysis, first in Europe and then elsewhere, allowing a more detailed succession to be elaborated (e.g. Godwin 1956, Terasmae 1967).
