Late Glacial Maximum

The Late Glacial (c. 13,000–10,000 years ago), or Tardiglacial ("Late Glacial"), is defined primarily by the beginning of the modern warm period, in which climates in the Northern Hemisphere warmed substantially, causing a process of accelerated deglaciation following the Last Glacial Maximum (c. 25,000–13,000 years ago). At this time, human populations, previously forced into refuge areas as a result of Last Glacial Maximum climatic conditions, gradually begin to repopulate the Northern Hemisphere's Eurasian landmass and eventually populate North America via Beringia for the first time.

Evidence for its occurrence stems from two main types of analysis. The first is the use of oxygen isotope stages (OIS) gathered from stratified deep-sea sediment cores. Samples are gathered and measured for change in isotope levels to determine temperature fluctuation for given periods of time. The second is a proxy measurement, the observation of certain reappearing fauna and flora fossils that can survive only in temperate climates, thus indicating warming trends for a given geographic area.

Archaeological evidence of settlement and resettlement in certain areas by humans also serve as proxy measurements. Towards the end of OIS 2 in which the Late Glacial Maximum occurs, the deep-sea sediment cores indicate a gradually warming climate, and the reappearance of certain warm-weather flora and fauna remains throughout the Northern Hemisphere correlate with that trend. A period of relatively brief cold oscillation, referred to as the Younger Dryas, is detected during OIS 2, as can be inferred from an increase in isotope weight.

Climate amelioration begins to occur rapidly throughout Western Europe and the North European Plain c. 16,000-15,000 years ago. The environmental landscape becomes increasing boreal except in the far north, where conditions remain arctic. Sites of human occupation reappear in northern France, Belgium, northwest Germany, and southern Britain between 15,500 and 14,000 years ago. Many of these sites are classified as Magdalenian, though other industries containing distinctive curved back and tanged points appear, as well. As the Fennoscandian ice sheet continued to shrink, plants and people began to repopulate the freshly deglaciated areas of southern Scandinavia.

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