The possible explosion of Mount Agung could prompt a cooling in global temperatures, according to several scientists.
The Bali, Indonesia, volcano has been billowing smoke for several days, with the surrounding areas on edge. It’s still unclear if the volcanic activity will actually lead to a large eruption, but if it does, it could affect more than just the region.
READ MORE: Ash drifts 7,600 metres from Mount Agung volcano
According to Anthony Farnell, Global News’ chief meteorologist, volcanoes have a history of changing the Earth’s climate with the gases and dust particles they emit. The emissions can quickly circulate throughout the planet, causing the cooling effects to be felt across continents.
The drop in temperatures is especially noticeable with volcanoes that are located in the tropics — such as Mount Agung.
READ MORE: Canadians among 100,000 ordered to flee erupting Mount Agung
But Farnell explains that the exact effects, specifically whether they will be felt in Canada, won’t be known until the eruption.
“If the volcano had a massive eruption tomorrow it would take one to two months for the ash and sulphur to travel around the Earth and the cooling would last from six months to a year,” he said.
“So we’d be potentially looking at winter lingering into spring and a cooler than normal summer in Canada if this were to occur.”
WATCH: Bali volcano at risk of ‘major eruption’, officials say
A climate scientist at NASA, Chris Colose, told Vox that the effect on climate depends on how big the eruption will be.
“Most eruptions do not have a meaningful climate impact, and so the risks associated with the eruption are limited to the nearby population,” he explained, noting a lot of it has to do with how much sulphur dioxide is emitted.
This is how it works, according to The National Center for Atmospheric Research: sulphur dioxide rises into the atmosphere and combines with water, creating sulphuric acid. The acid then forms tiny droplets that cool the Earth and make it difficult for sunlight to penetrate. They can stay in the atmosphere for up to three years, and move around during this time, causing a worldwide cooling.
WATCH: Bali village coated in ash, mud rushes into river as Mount Agung volcano continues to erupt
In Mount Agung’s case, there is a history of big eruptions. In 1963, the volcano exploded killing more than 1,600 people. The devastating event cooled the Earth’s temperatures for about one year, the Washington Post reports.
Another volcano in the region, Mount Pinatubo in the Philippines, caused oceans to cool enough to temporarily lower water levels in 1991.
Possibly the most notable case of an eruption cooling the Earth occurred more than 100 years ago.
WATCH: Bali flights resume as volcano still threatens to erupt
The 1815 explosion of Mount Tambora, which is the largest eruption of a volcano ever recorded, caused temperatures to drop up to 3 C around the globe.
READ MORE: Bali volcano alert raised to highest level, 100K people ordered to evacuate immediately
The Indonesian eruption led to a period dubbed “The Year Without a Summer” across North America and Europe. There was heavy snow and frost during the typically warm season. Farmers’ crops also died, leading to a shortage of food and higher prices.
Mount Agung being closely watched
While Mount Tambora’s tale is one extreme example, the Bali volcano is also concerning.
The billowing smoke closed the local airport for several days, stranding thousands of visitors before the winds changed and flights resumed.
The Darwin Volcanic Ash Advisory Centre has warned that the explosion could be quite big.
WATCH: Airport opening proves too brief for Kelowna family stuck in Bali
“Volcanological sources indicate a larger eruption is still possible,” it said on its website.
An estimated 90,000 to 100,000 people normally live in the danger area near the volcano.
— With files from Reuters