History As Told By Trees

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A sample from Siberia, with the core dating from 1637 and the outer ring from 2011, hangs on a wall at the research lab on the University of Arizona campus in Tucson. Adriana Zehbrauskas for The New York Times

Thanks to Jim Robbins, as always:

Chronicles of the Rings: What Trees Tell Us

Studying the historical data stored in centuries-old trees is a burgeoning field, with labs around the world learning more about historical patterns of weather and climate and the effects on humans.

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Wood samples for research at the Laboratory of Tree Ring Research at the University of Arizona. Adriana Zehbrauskas for The New York Times

TUCSON — From the early 1700s until the 1960s, the fast moving river of wind known as the North Atlantic Jet Stream, which drives weather extremes over Europe, was pretty steady on its course.

Then it became less predictable. But instrument data alone can’t tell the jet stream’s movements for comparison over the centuries, given that scientists began keeping records of weather events via instruments only in the late 19th century. Continue reading