Firing the sky

On February 19, 1600, the Peruvian stratovolcano Huaynaputina exploded in the most violent eruption in South American recorded history. From the article:

"In 1600, Huaynaputina in South America erupted, throwing life out of gear, taking lives and causing economic ruin. Its effect was felt all over the world.
On February 19, 1600, in the upland region of southern Peru, a volcano named Huaynaputina exploded. Recorded as the largest volcanic explosion in South America, it saw a volcanic eruption up to 30 km, which not just destroyed villages for many miles but also impacted societies and agriculture world-wide.

Huaynaputina, meaning a young volcano, did not have an identifiable mountain profile, but instead was a large volcanic crater. The volcano is part of the Central Volcanic Zone, the segment of the Andes running through Peru and Chile.

Slow build up

On February 15, many people felt earthquakes. By February 18, the quakes were getting more frequent — once every five to six minutes. The quakes were powerful enough to wake people from their sleep. Then on February 19, between 11 a.m. and 1 p.m. there were two major earthquakes. This caused widespread panic. Many houses were destroyed, large landslides occurred, and cracks and deformations appeared on the surface of the earth.

In the evening, at 5:00 p.m., Huaynaputina exploded. Huge explosions that sounded like canon fires roared around the summit and the crater began to spew burning ash into the sky. Hot gas rose to about 35 km in height and ash began to fall like snow. Earthquakes that accompanied these blasts were severe and destroyed Arquipa and Moquegua cities in the Andean region almost 75 km away. The villages of Tasata and Calicanto were buried beneath more than 10 feet of molten lava. Ash fall was reported 250 -500 km away, throughout southern Peru and in what is now northern Chile and western Bolivia.

The entire eruption is described to have been in five stages. The Plinian phase or the first phase began on February 19 and lasted till the next day. Pumice (a light-colored, extremely porous igneous rock that forms during explosive volcanic eruptions) fell from the volcano almost seven kilometres away and the winds carried the finer dust to the Pacific Ocean. The second phase saw ash falls. The third phase was destructive and acidic lava flew out of it. Crystal ash fall was deposited over the neighbouring areas in the fourth phase and the fifth phase ended with surge deposits.

Approximately 1,500 people were killed, villages were buried, and a total loss of crops, cattle, and seeds disrupted trade for years. Epidemics, famine, and poverty added to the general ruin. Secondary flows that were not directly related to the eruption kept rushing from the mountain over the next few months and it took about 150 years for the affected area to recover from all losses.

The eruption lasted from February 19 to March 6 and the ash from the eruption was widespread. Today, one-centimeter-thick layers can be found no farther than 200 km northwest of the eruption, and the deposits in the vicinity of Arequipa are about 10 cm.

Global impact

Huaynaputina injected a large amount of sulphur into the atmosphere which reacted with water to form sulphuric acid droplets. These droplets in turn reflected some of the sunlight and prevented the rays from hitting earth almost for a year. Tree rings showed that the temperature drop resulted in lesser growth that year. In fact, various other countries also reported similar readings. Russia claimed that it saw the worst famine and exceptionally cold winters. France and Germany reported delay in wine harvesting and production. In China, peach trees bloomed late, and in Japan, Lake Suwa had one of its earliest freezing dates in 500 years."