” Working with a continuous record of Arctic climate reaching back 3.6 million years, researchers have documented a period when the region was significantly warmer and wetter than it is today and when the atmosphere’s inventory of carbon dioxide was comparable to today’s levels.
The period the team has analyzed covers the first 1.4 million years of the record, when the region’s climate shifted from warm and wet to conditions that signaled the start of ice ages.
This period is of interest in part because the warmth persisted despite periodic shifts in Earth’s orbit that reduced the intensity of sunlight reaching the region.
The evidence is captured in a 1,034-foot core sample the team drew from the bottom of Lake El’gygytgyn, known informally as Lake E. It formed 3.6 billion years ago after a meteor punched a crater in Russia’s northeastern Arctic. The crater filled to form a lake 7 miles across and some 560 feet deep. The area around the lake managed to remain ice free during the ebb and flow of continental ice sheets during the Pleistocene ice ages, allowing sediment layers – and the pollen and other climate indicators they contain – to build up uninterrupted for the last 3.56 million years.”
- More ‘ice free Arctic’ claims – we’ve heard it all before (wattsupwiththat.com)
- Ice-Free Arctic May Be Near, Study Suggests (livescience.com)
- The Arctic was once warmer, covered by trees (sciencenews.org)
- Climate Record From Bottom Of Russian Lake Shows Arctic Was Warmer Millions Of Years Ago (eurasiareview.com)