Some 400 years ago, in the upland region of southern Peru, a volcano named Huaynaputina exploded; catastrophically. It was February 19, 1600, and is recorded as the largest volcanic explosion ever in South America. Scientists believe that its eruption may have had societal and agricultural impacts worldwide.
Kenneth Verosub, a geophysicist at the University of California, Davis and colleague Jake Lippman see a connection between the 1600 eruption of Huaynaputina, a little-known peak in Peru, and one of the greatest famines ever to strike Russia. “People have long known about the eruption and have long known about the famine, but no one has previously linked the two,” Verosub says.
In February 1600, Huaynaputina, a relatively inconspicuous peak in the Andes of southern Peru — the name means “new volcano” — catastrophically exploded. The eruption, the largest in South America in written or oral history, lasted at least two weeks and belched as much as 12 cubic kilometers of ash, much of that spewing into the atmosphere during the first two days.
Significant quantities of ash smothered the region, says Charles Walker, a historian at UC Davis. “Some people didn’t see the sun for months, and agricultural production was devastated for the next two years,” he notes.
Huaynaputina lofted immense amounts of sulfur dioxide into the atmosphere, where it reacted with water vapor and then condenses into Earth-cooling droplets of sulfuric acid, which can destroy high-altitude ozone. Eventually the droplets are cleansed from the air by natural processes. The amount of sulfur-bearing compounds deposited on ice in Greenland and Antarctica in the months after the eruption suggests that Huaynaputina spewed between 16 million and 32 million metric tons of sulfur into the air.
The chilling effects of Huaynaputina’s eruption in 1600 were substantial and were felt worldwide, he and Lippman reported. Analysis of tree ring data gathered throughout the Northern Hemisphere indicate that 1601 was, on average, the coldest year out of the last 600. In Switzerland, 1600 and 1601 were among the coldest years between 1525 and 1860. In Estonia, the winter of 1601–1602 was the coldest in a 500-year period. In Latvia, the late date of ice breakup in the harbor at Riga indicates the winter was the worst in the 480 years before today. In Sweden, record amounts of snow in the winter of 1601 were followed in the spring by record floods. People around the world felt the effects of Huaynaputina’s changes to climate.
In general, the larger the volcanic eruption, the bigger the cooling effect and the longer that effect lasts, sulfur content of its aerosols notwithstanding. Scientists categorize eruptions according to the Volcanic Explosivity Index, a parameter that depends on factors such as how much material is thrown from the peak and the height of the ash plume that’s produced.
The Huaynaputina eruption of 1600 falls into VEI category 6, which denotes an eruption with an ejecta volume greater than 10 cubic kilometers and a plume height that exceeds 25 kilometers.
Since 1601, there have been five category 6 eruptions, including Laki (1783), Krakatau (1883) and Pinatubo (1991). However, none of these events spawned adverse societal effects on a global scale as Huaynaputina did. In part, Huaynaputina’s sulfur-rich plume could have rendered the peak’s eruption inordinately powerful.
Climate at the time could have played a role as well, says Verosub. In 1600, the world was in the midst of the Little Ice Age, typified by harsh winters, springs and summers much cooler and wetter than normal, and shorter-than-average growing seasons. A large volcanic eruption during that period would have depressed average temperatures even further.
“What happens if another major eruption happens today?” Verosub asks. “If we lower the growing season globally, are we looking at a food crisis? … We’ve got a really stressed system, and if we hit it hard, is it going to collapse? I think that’s worth thinking about.”
Jason McManus via sciencenews.org and livescience.com