by K. Richard, Sept 5, 2022 in NoTricksZone

Abundant polar bear remains dating to 8000 to 9000 years ago have been found on Zhokhov Island, which is today surrounded by year-round sea ice (even in summer). This Arctic latitude (76°N) is too cold and thus too ice-covered for polar bears to inhabit today.

During the Early Holocene CO2 concentrations ranged between 255 to 265 ppm, and yet the Arctic was 5-7°C warmer than it is today and many regions that are now sea ice-covered were sea ice-free.

For example, Zhokhov Island is tundra and treeless today. It’s surrounded by permanent sea ice, making it inaccessible to wildlife.

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