While looking through historic records, medieval and environmental historian Martin Bauch noticed a particularly serious crop failure that began in northwestern Italy in late 1345, just two years before the Black Death broke out in Europe. He analyzed regional grain trade records during the time and looked at tree ring and ice core data for signs of what might have been happening with Earth’s climate. He hypothesizes, in a new paper published today, that an unnamed volcanic eruption may have set off a chain of events that triggered the Black Death pandemic.

The hypothesis: The as-of-yet unidentified eruption triggered several seasons of climate instability and crop failures, reports senior writer Meghan Bartels. That instability, in turn, forced several Italian states to import grain stores from new sources—specifically, from regions surrounding the Black Sea. Riding along on those grain stores, the researchers posit, were fleas infected with Yersinia pestis, the bacterium that causes the plague.

What the experts say: “Climate is regularly discussed as a driver in the Black Death; however, quite what mechanism links climate to plague is relatively difficult to unpick,” says Henry Fell, a disease ecologist studying the plague at the University of Nottingham and the University of York in England. Why difficult? Plague is an intricate disease system, with people, bacteria, fleas and multiple species of rodents all interacting in time and space.

Out in the open ocean, monstrous waves much higher than neighboring waves can suddenly appear. However, a new study has found a way to potentially forecast the frightening phenomenon. Scientists analyzed 27,505 wave measurements recorded over 18 years by laser sensors on an oil and gas platform in the North Sea. They found that when swells from several waves overlap in certain patterns, these sharpened crests can stack dramatically to build a single, towering wall of water.

Why this matters: Scientists could someday use the measurable patterns as a fingerprint to predict the rogue waves. This could help protect human-built vessels and offshore structures that may be exposed to the damaging wake of these waves.

What the experts say: “Our civilization critically depends on shipping and offshore activities, and there is a massive international research effort aimed at understanding rogue waves,” says Keele University physical oceanographer Victor Shrira, who was not involved in the study. “Even the largest vessels and structures are not immune.” —Andrea Tamayo, Newsletter Writer