Siberian meteor crater records nearly 3 million years of climate history

About 3.6 million years ago a large meteor crashed into Siberia about 100 miles north of the Arctic Circle.  The impact created an eleven-mile wide crater that became a lake.  Lake El’gygytgyn collected sediments which record the climate and environmental conditions.  Since this area was not eroded by continental glaciers, researchers were able to collect sediment cores that provide “a continuous high-resolution record from the Arctic spanning the past 2.8 million years.”

The cores record eight warm periods, four of which were investigated in detail: normal interglacials from 12,000 years ago to present, and one at about 125,000 years ago, and two “super” interglacials at 400,000 years ago and 1.1 million years ago during which the Arctic temperatures were as much as 5 C (9 F) warmer and 12 inches of annual rain wetter than normal interglacials.

The researchers suggest that Greenland’s ice sheet could not exist during the “super” interglacial periods.  Also, the researchers note that disintegration of the West Antarctic ice sheet occurred at the same time as the “super” interglacials suggesting that the warming events were global.

The paper abstract says: “Climate simulations show these extreme warm conditions are difficult to explain with greenhouse gas and astronomical forcing alone, implying the importance of amplifying feedbacks and far field influences. The timing of Arctic warming relative to West Antarctic Ice Sheet retreats implies strong inter-hemispheric climate connectivity.”

This research provides more physical evidence that extreme warming and climate fluctuations occur as part of natural variation.  This research implies: 1) The globe has been much warmer without human influence during multiple periods over the past 2.8 million years, 2) IPCC climate models are incapable of reproducing past temps and therefore unable to project future temps, and 3) global warming far exceeding alarmist IPCC projections has occurred several times in the past without triggering any “tipping points.”

More details and a video are available from Phys.org here.  Additional comments are posted herehere (graphs), and here.

See also:

Ice Ages and Glacial Epochs

When Antarctica Freezes Over

A 2485-year record shows current warming is a natural cycle

How Mother Nature Fools Climate Scientists

Rare mineral records Antarctica temperature history

Norwegian research shows that current warming is not unusual

More evidence that current warming is not unusual

Ice Follies and Hiding the Decline

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