Guest essay by Eric Worrall
The grumbling Bali Volcano Mount Agung has not erupted yet, but experts are already talking up the dramatic short term global cooling it will cause when it blows.
Bali volcano: Here’s why the Earth will get a little cooler after Mount Agung erupts
By Alle McMahon
Something very interesting will happen when Bali’s Mount Agung finally erupts: the Earth will become a little bit cooler.
Yep. It’s not exactly what you’d expect after a volcanic eruption, which will see molten lava spewed into the air.
But don’t get too excited, it will far from reverse the effects of global warming.
Global temperatures dropped last time Agung erupted
Mount Agung last erupted in 1963 after laying dormant for decades.
When it erupted, experts said global atmospheric temperatures dropped by 0.1-0.4 degrees Celsius.
That might not sound like much, but it’s quite a significant drop when you consider the last ice age occurred when global temperatures were only 5C cooler than they are now.
But the effect didn’t last for long
According to Professor Arculus, that sulphuric acid haze can persist in the stratosphere for a few years, but eventually the droplets will drop back to Earth.
“They’re small enough that they can stay up there for a while … but eventually they get rained out,” he said.
And that’s why the temperature drop will far from cure global warming.
Last time Mount Agung erupted in 1963-4 just under 2000 people died. Indonesia is taking evacuation of the region around the volcano very seriously.