BALI’S volcano eruption could plunge the earth into a prolonged cold spell as scientists warn Mount Agung explosion could reverse global climate change for up to five years.
Volcanic debris, ash and other particles have continued to spew out of the volcano, leaving a seven-mile high hazardous cloud above the mountain top.
Evacuation orders are in place for the 100,000 villagers and citizens living within six miles of the mountain, while thousands of tourists remain stranded after the main airport was closed for more than two days.
But experts have warned the Bali volcano may affect the whole world, possibly cooling the planet for up to five years.
And the result will be in a reverse of global warming, as the planet’s temperatures cool instead of increasing as projected.
Scientists have known for a long time volcanic eruptions can alter the planet’s climate for months on end, as millions of gases and particles spread through the atmosphere.
But how much this is changed depends on what is being erupted - with a volcanic explosion causing the ideal conditions to trigger a drastic change to earth’s temperature.
NASA climate scientist Chris Colose said: “To have a notable climate impact, there needs to be an explosive enough eruption (to get material in the stratosphere) and a sulphur-rich eruption (the SO2 converts to sulphate aerosol, which is what radiatively matters).
“If these conditions are met, the eruption cools the surface/troposphere and warms the stratosphere, the opposite of both patterns associated with CO2 increases. But both are very short-lived (~years).”
In 1963, Mt Agung eruptions reached as high as 16 miles (26km) above sea level. about 1,110 people were killed in the devastating blast.
The 1963 eruption was not exceptional in volume of ash produced, according to Mr Colose, but “somewhat unique in sulphur released”.
He said: “For volcanoes to do anything to climate you need a lot of SO2 released and a high enough plume for that SO2 to get into the stratosphere.
“The SO2 particles have sizes comparable to a visible wavelength and are strongly scattering to incoming sunlight, cooling the planet
“If a similar SO2 release occurred, could cool planet for 1-2 years, and then a recovery.”
Fellow scientists remarked that Agung’s recent behaviour matches the build up of that fateful explosion in 1963, suggesting a similar amount of sulphur dioxide could be released into the atmosphere.
The last eruption knocked global temperatures down by 0.2 degrees Celsius for a year, but this latest one could see falling temperatures for around two years - only returning completely to normal by 2023.
Climate researcher Zeke Hausfather said: “This projection, which is based on the historical relationship between volcanic eruptions and temperature, suggests that an Agung eruption would reduce global temperatures between 0.1C to 0.2C in period from 2018 to 2020.”
A report from the Washington Post added the eruption could alter the global temperature for months and maybe even years to come.
It said: "In the short term, ash particles would cause regional cooling, as the layer of dust prevents some sunlight from reaching the ground.
“In the long term, sulphur dioxide would mix with water droplets in the atmosphere, spread across the globe and reflect sunlight for up to three years. Average global temperature could decrease significantly.”
Alan Robock, an environmental scientist at Rutgers University, explained that once high in the sky, sulphur dioxide reacts with water to produce droplets that can linger for a year or more.
And when sunlight hits these droplets, energy is reflected back into space, depriving Earth of substantial amounts of sunlight and therefore lowering temperatures.