As news of the volcanic eruption Saturday in the Pacific nation of Tonga prompted shock and concern across the globe, the event also sent literal shockwaves through the atmosphere — including some that could be detected at O’Hare International Airport and other Chicago-area observation sites, according to forecasters with the National Weather Service’s Romeoville office.
“I was initially surprised, but it does make sense,” Brian Leatherwood, a meteorologist at the weather service, said about the shockwaves. Leatherwood said the spikes in pressure were discovered by a fellow meteorologist who “put two and two together” after the volcano erupted.
An initial shockwave moving east from the volcano was detected in Chicago just before 8:30 a.m. Saturday, according to a thread posted by the weather service on Twitter. A second shockwave, which moved west around the planet before arriving in Chicago, hit early Sunday morning, according to the weather service.
During a shockwave, air pressure increases more than usual, as a result of air being quickly compressed, and then decreases, due in this case to the volcanic explosion, Leatherwood explained.
“You can almost think of a volcano as uncorking a Champagne bottle. There’s just a lot of pressure built up,” said Renee Duff, a meteorologist with AccuWeather.
When the pressure is released, it can cause a “big disruption” to the surrounding atmosphere, she said. Similar to dropping a rock in water, the disruption to the fluid-like atmosphere comes in the form of waves that ripple out from the explosion site, Duff said.
A photo taken on Jan. 17, 2022 shows an eruption on the Hunga Tonga-Hunga volcano. (Planet Labs PBC/Getty Images)
Typically, a weather system can change air pressure in a matter of hours, but the changes observed in the volcanic explosion occurred much more quickly, Leatherwood said. Although the pressure change was detected locally, people in Illinois wouldn’t have felt any noticeable difference as a result, he added.
The explosion largely cut off communication with Tonga when a single cable that connects Tonga’s communications with the rest of the world was severed, leaving thousands of concerned relatives unable to establish contact with loved ones on the island, according to The Associated Press. The explosion also caused tsunami waves and volcanic dust to contaminate the water supply. A government agency in Fiji warned of the possibility of acid rain in the area and asked its residents to cover household water tanks, according to published reports.
New Zealand and Australia were finally able to send surveillance flights to determine the extent of the damage Monday. A thick ash cloud above Tonga initially impaired such flights Sunday, the day after the Hunga Tonga-Hunga Ha’apai volcano erupted underwater about 40 miles north of Nuku’alofa, the island nation’s capital.
In the short term, there’s a risk for respiratory issues due to the ash for people near the explosion site, Duff said. In the longer term, there’s a potential for global cooling this spring and summer, as ash could block a small amount of sunlight, she added — a phenomenon that scientists will be following in the coming months.
No casualties in Tonga had been confirmed as of Monday. Two women reportedly died in Peru — some 6,600 miles away — amid “abnormal waves” after the eruption.
Antenna installed in Big Marsh Park will allow scientists to track the life story of migratory birds passing through Chicago
Jan 13, 2022
Billion-dollar disasters in 2021 — including the costliest winter storm on record — caused extensive damage in Illinois and across the country
Jan 12, 2022
Breaking Sports Les Grobstein, Chicago’s sports encyclopedia and longtime radio host, dies at age 69
4h
Elite Street Lake Geneva mansion owned by late investment manager Richard Driehaus sells for $36M, a Wisconsin state record
2h
Breaking News Couple who got $105,000 bill from Chicago Public Schools over residency dispute fights back in court
Jan 16, 2022