Hello and welcome to more or less on the BBC World Service. We're your weekly guide to

the numbers and I'm Tim Halford. Something erupted on a more or less listeners' Facebook

feed recently. A friend shared an image which states that one burp from Mount Etna puts

more than 10,000 times a CO2 into the atmosphere than mankind has during our entire time on Earth.

Can this possibly be true?

A volcanic burp? Unsurprisingly it turns out that's not a technical term. Mike Burton, a

volcanologist we've been talking to at the University of Manchester in the UK, says

we should talk about a short term episode of volcanic activity instead. He spent seven

years working at Mount Etna in Italy, Europe's most active volcano.

CO2 produced for a metna is a very large gas emission in the context of volcanoes. We're

talking about six million tons of CO2 per year.

Six million tons by the way is six billion kilograms. Mike reminds us this isn't just happening

during eruptions. Mount Etna is always releasing gas, a process known as degassing for reasons

that I probably don't need to explain. In fact, the amount of CO2 emitted during degassing

dwarfs that of short term volcanic episodes such as eruptions. So we've discovered that

whether it's erupting or not, Mount Etna is producing a serious amount of carbon dioxide

even by the standards of a volcano. But how does that compare to emissions caused by human

activities? Man-made carbon dioxide emissions are far higher than anything Mount Etna can produce.

And what is it that humans are doing to create all those emissions? Here's Dr. Laura Wilcox

of the University of Reading in the UK. We tend to split them down by sector. So roughly

on average about 50% of our CO2 emissions are coming from electricity and heat generation.

We see about 20% from transport and other 20% from manufacturing instruction. Around

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