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Climate change and prehistoric human populations: Eastward shift of settlement areas at the end of the last ice age

by University of Cologne, Apr 3, 2025 in ScienceDaily

A new study sheds light on how prehistoric hunter-gatherer populations in Europe coped with climate changes over 12,000 years ago. Led by scientists from the University of Cologne, a team of 25 prehistoric archaeologists from twenty European universities and research institutions revealed significant shifts in population size and density during key periods at the end of the last Ice Age, specifically during the Final Palaeolithic between 14,000 and 11,600 years ago. The study has been published in PLOS One under the title ‘Large scale and regional demographic responses to climatic changes in Europe during the Final Palaeolithic’.

 The results reveal that the first establishment of a larger human population in north-eastern central Europe during the Final Palaeolithic was followed by a dramatic population decline during the last cold period (Greenland Stadial 1) of the Ice Age. This decline reduced the total population of Europe by half. However, the study found that some areas in central Europe show stability or even a slight increase in population size against the general trend. The team interprets this finding as evidence of human migration towards the east in response to worsening climate conditions.
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climate-debate

New Study: Corals Thrived When Global Sea Levels Were Meters Higher Than Today 6000 Years Ago

by K. Richard, Apr 3, 2025 in NoTricksZone 

Coral reefs expand and thrive as sea levels rise, whereas they undergo millennia of growth hiatuses and “turn-off” or “mass mortality” phases when sea levels fall.

According to a new global sea level reconstruction (Feldman et al., 2025), global sea levels were meters higher than today 7000 to 5000 years ago. Global sea levels fell thereafter throughout the late Holocene.

From approximately 4500 years ago until 640 years ago, previously thriving coral reefs endured “mass mortality” and “turn-off” phases due to incrementally declining accommodation space in the Red Sea region.

This millennial-scale “turn-off” reef growth period was not just limited to this study area, but coral cover decline has been a global phenomenon associated with global sea level fall throughout the late Holocene.

“A global hiatus in coral reef development […] was largely driven by eustatic sea level drop during the late Holocene and caused a lack of vertical accommodation space…”

“In this study, we propose not just a local sea level condition causing specific reef turn-offs or hiatuses, but rather a global phenomenon of sea level fall.”

“A reduction in accommodation space through receding sea levels resulted in mass mortality or sea level constrained corals.”

Considering rising sea levels are advantageous to corals and falling sea levels largely eliminate the potential for growth, future sea level rise may lead to a “significant increase in coral cover”.

“Future sea level rise could provide additional accommodation space for currently sea level-constrained reef systems, potentially leading to a significant increase in coral cover.”

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