Winter Is Coming Paradox: Researchers Uncover the Surprising Cause of the Little Ice Age

Finally. The "Atlantic Meridional Overturning Circulation (AMOC), which is like a planetary conveyor belt" is being considered more carefully by climate scientists. The article does some comparing and contrasting to current times.

It is interesting to consider that China's seafaring commerce in the 1400s coincided with the weather changes covered in the research.

"Using many detailed marine records, Lapointe and Bradley discovered that there was an abnormally strong northward transfer of warm water in the late 1300s which peaked around 1380. As a result, the waters south of Greenland and the Nordic Seas became much warmer than usual. “No one has recognized this before,” notes Lapointe."
[. . . ]
"Over the course of a few decades in the late 1300s and 1400s, vast amounts of ice were flushed out into the North Atlantic, which not only cooled the North Atlantic waters, but also diluted their saltiness, ultimately causing AMOC to collapse. It is this collapse that then triggered a substantial cooling."