Etna and other volcanoes are not the cause of climate change

After theEtna eruption, which occurred in recent days, an old hoax has started circulating again:Volcanoes emit more CO₂ of human activities. Etna has just told the geniuses of the Last Generation who is in charge, says a profile on Twitter.Those who relaunch this hoax think, in this way, of giving a raspberry to the activists and of revealing to the world truths that we all had before our eyes, but which we did not see because we were blinded by propaganda gretina And green.Because the idea, of course, is always that everything that revolves around climate change originates from the heads of activists.Scientists didn't know that volcanoes emit CO₂, nor that the Sun is larger than the Earth, as a collaborator of the newspaper informs us The Truth.Let's see how things are.

In 2022, the energy sector, the one responsible for the majority of emissions, produced 36.8 billion tons of CO₂.Volcanic activities generate every year 200-400 million tons of CO₂.Two orders of magnitude difference, 100 times less than emissions from the energy sector alone.If you add the CO flows₂ originating from all volcanic processes on Earth – from inactive volcanic areas, volcanic lakes, hydrothermal vents – these natural emissions amount to less than 2% of the anthropic ones.

Volcanism and other geological phenomena can trigger climate modifications through the release of greenhouse gases over long time scales, as happened about 56 million years ago during the Paleocene-Eocene Thermal Maximum (PETM).The temperature then increased by 5-9 degrees, but over a period of approximately 170 thousand years.A very short time from a geological point of view, but much longer than the handful of decades it took us to modify the Earth's climate (most human emissions are concentrated in the second half of the 20th century).We humans are sending CO₂ into the atmosphere at one speed 9-10 times greater.

Large volcanic eruptions (and Etna is not) can have short-term climate effects not due to CO₂, but of the emission of massive quantities of aerosols fired into the atmosphere.It happened, for example, in 1815 following theMount Tambora explosion in Indonesia.It was a huge eruption, with a volcanic explosiveness index (VEI) equal to 7, out of a maximum of 8.They are eruptions that produce volumes of material exceeding 100 cubic kilometers.The aerosol mass projected into the sky by Tambora reached the stratosphere and reached the northern hemisphere, from Europe to the United States.1816 went down in history as "the year without a summer".The season was colder than usual and agricultural crops collapsed.

In 1991 theeruption of the Pinatubo volcano in the Philippines it emitted 15-20 million tons of sulfur dioxide.It is estimated that this powerful eruption (VEI= 6) caused a drop in global temperatures by about half a degree.It was a temporary effect, lasting about a year, certainly not enough to reverse a warming trend that was already underway at that time.But this shows, again, that large eruptions in the short term can cause cooling, not warming.The website of United States Geological Survey remember that the 1980 eruption of Mount St.Helens (VEI=5) «released approximately 10 million tonnes of CO into the atmosphere₂ in 9 hours.It takes humanity just 2.5 hours to emit the same amount."Many continue to underestimate the amount of CO₂ that human activities have managed to produce since the Industrial Revolution. It's about of a number of tons with 12 zeros.

The idea that the climate is like a gigantic contraption on which we, little human beings, cannot exert any influence, and that it is even presumptuous to even think about it, is an old argument that denialist rhetoric exploits to obscure the facts.It is comforting to be lulled by this belief, because it allows us to ignore our responsibilities:the climate is going the way it should go and we can not care and continue using coal, oil and gas.This is the real presumption.The reality is that we humans can, indeed, change the climate.The effects of our activities on the climate overlap with natural variability, which continues to exist. The contrast between human And natural turns out, as in other cases, to be misleading.Our activities have changed the climate through the same greenhouse gases and natural mechanisms that occurred during other climate changes that occurred in the past, when humans were not around.Current global warming is both anthropic, due to its causes, and natural, due to the mechanisms that make it possible.

The Twitter profile that, together with others, relaunched the hoax writes in its biography that «the truth is much more complicated than falsehood.This is why falsehood is more popular.".It seems like a mockery, the portrait of a world in reverse.But because it is an Orwellian conception of truth:their truths are lies.

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