The research summarized below supports the thesis of Steven Koonin’s recent Unsettled book.
(p. D2) Long ago, the two oceans existed in harmony, with warm and salty Atlantic waters gently flowing into the Arctic.
. . .
But everything changed when the larger ocean began flowing faster than the polar ocean could accommodate, weakening the distinction between the layers and transforming Arctic waters into something closer to the Atlantic. This process, called Atlantification, is part of the reason the Arctic is warming faster than any other ocean.
. . .
In a paper published Wednesday [Nov. 24, 2021] in the journal Science Advances, Dr. Tesi and colleagues were able to turn back time with yard-long sediment cores taken from the seafloor, which archived 800 years of historical changes in Arctic waters. Their analysis found Atlantification started at the beginning of the 20th century — decades before the process had been documented by satellite imagery. The Arctic has warmed by around 2 degrees Celsius since 1900. But this early Atlantification did not appear in existing historical climate models, a discrepancy that the authors say may reveal gaps in those estimates.
“It’s a bit unsettling because we rely on these models for future climate predictions,” Dr. Tesi said.
Mohamed Ezat, a researcher at the Tromso campus of the Arctic University of Norway, who was not involved with the research, called the findings “remarkable.”
“Information on long-term past changes in Arctic Ocean hydrography are needed, and long overdue,” Dr. Ezat wrote in an email.
For the full story, see:
(Note: ellipses added.)
(Note: the online version of the story has the date Nov. 27, 2021, and has the same title as the print version. The last three sentences quoted above, appear in the online version, but not in the shorter print version. Where there is a slight difference in wording between the two versions, the passages quoted above follow the online version.)
The paper co-authored by Tesi is:
Tesi, Tommaso, Francesco Muschitiello, Gesine Mollenhauer, Stefano Miserocchi, Leonardo Langone, Chiara Ceccarelli, Giuliana Panieri, Jacopo Chiggiato, Alessio Nogarotto, Jens Hefter, Gianmarco Ingrosso, Federico Giglio, Patrizia Giordano, and Lucilla Capotondi. “Rapid Atlantification Along the Fram Strait at the Beginning of the 20th Century.” Science Advances 7, no. 48 (Nov. 24, 2021): eabj2946.
The Koonin book that I mention above is:
Koonin, Steven E. Unsettled: What Climate Science Tells Us, What It Doesn’t, and Why It Matters. Dallas, TX: BenBella Books, 2021.