Amazing stuff! Climate changes all the time! What caused the global warming 7,000 years ago? Unfortunately, the article does not elaborate at all!
Anthropogenic climate change is largely demagoguery spread by some scientists like this (Professor Briner of this study) and others!
According to Google search: "Around 7,000 years ago (circa 5000 BCE), the global human population was likely in the millions, possibly reaching 5 million". Compare that to the current global human population of about 8 billion.
I bet, all current so called climate models have not been able to backcast this event correctly! Climate model forecasts up to 2100 are at best scenarios and simulations at worst propaganda and demagoguery!
These phony researchers behind this study even cite "projections of warming by 2100 CE". What a junk science! Which is reinforced by following quote "“It may only be a matter of time before [Prudhoe Dome] begins peeling back again from today’s human-induced climate change [???].” Jason Briner, professor and associate chair of Earth sciences"
"... The intensity of that glow revealed that the Prudhoe Dome sediment was last exposed to daylight sometime between 6,000 and 8,200 years ago.
“This means Prudhoe Dome melted sometime before this period, likely during the early Holocene, when temperatures were around 3 to 5 degrees Celsius warmer than they are today. ..."
"In northwestern Greenland, researchers working on the GreenDrill project have cored through a 500-meter-thick ice dome. They found something startling: the dome completely disappeared 7,000 years ago. And it might do it again.
Nearly 80% of Greenland is covered in frozen water by the fittingly named Greenland Ice Sheet. This sheet comprises the second-largest body of water in the world, stretching over about 660,000 sq miles (1.7 million sq km), and containing roughly 0.7 million cubic miles (2.9 million cubic km) of ice, representing a significant portion of the Earth's freshwater supply. ..."
From the abstract:
"Projections of future sea-level rise benefit from understanding the response of past ice sheets to warming during past Quaternary interglacials. Constraints on the extent of inland Greenland Ice Sheet retreat during the Middle Holocene (~8–4 thousand years before present) are limited because geological records of a smaller-than-modern phase largely remain beneath the modern ice sheet.
We drilled through 509 metres of firn and ice at Prudhoe Dome, northwestern Greenland, to obtain sub-ice material yielding direct evidence for the response of the northwest Greenland ice sheet to Holocene warmth.
Here we present infrared stimulated luminescence measurements from sub-ice sediments that indicate that the ground below the summit was exposed to sunlight 7.1 ± 1.1 thousand years ago.
This proposed complete deglaciation of Prudhoe Dome, coeval to reduced extent at other ice caps across northern Greenland, is consistent with interglacial-only δ18O values from the Prudhoe Dome ice column and ice depth–age modelling. Our results point to a substantial response of the northwest Greenland ice sheet to early Holocene warming, estimated to be +3–5 °C from palaeoclimate data. This range of summer temperatures is similar to projections of warming by 2100 CE. [???]"
Greenland’s Prudhoe Dome ice cap was completely gone only 7,000 years ago, first GreenDrill study finds (original news release) "Core samples pulled from beneath ice sheet suggest region is highly sensitive to the temperatures of our current interglacial period"
Deglaciation of the Prudhoe Dome in northwestern Greenland in response to Holocene warming (no public access)
Holocene deglaciation of Prudhoe Dome, northwest Greenland (preprint, open access)
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