Watch 60 Years Of Eruptions Shake The Planet In This Amazing Animation - Forbes

Boom! Here are 60 years of quakes and volcanic eruptions.

Global Volcanism Program

After seeing how many people were interested in the 100-year animation of the world’s earthquakes, it only seemed fair that I’d point the way to a volcanological equivalent. So, courtesy of the Smithsonian Institution’s Global Volcanism Program, here it is! This spectacular web application – the Eruptions, Earthquakes & Emissions app, or E3 – shows not just earthquakes but volcanic eruptions since 1960, the date from which the record keeping of such things really took off.

The GVP already does a phenomenal job at keeping track of the world’s ongoing volcanic eruptions – 40 or so of which are going on at any one time, which, yes, is perfectly normal – but E3 certainly helps remind us just how volcanically active this planet really is. It's not available as a video, but you can access the app if you click here. Feel free to zoom into various parts of the world, where plenty of smaller events can be seen popping up that otherwise fade into the background on the global scale.

The app already has a great FAQ, but here are some key points and bonus information here, just in case you’re curious.

What do the size of the triangles represent?

On this particular animation, earthquakes below a magnitude 5.0 aren’t included, but no worries; this animation's starring feature is (and I may be biased) its documentation of the planet's volcanic eruptions. Little triangles flash up whenever one occurs, and the size of the triangles correspond to the magnitude of the eruptions according to the Volcanic Explosivity Index (VEI).

The VEI, which has been around for four decades now, is measured using a handful of metrics: the amount of fresh, newly created volcanic material that comes out during the eruption is a big factor, as is the height of the plume of ash, as is the style of the eruption (effusive, lava producing styles all the way up to cauldron-creating colossal explosions). It’s a way to gauge the “size” of the eruption, and as with earthquakes and the moment magnitude scale, those higher on the scale happen less frequently.

At one end of the scale, you have VEI 0. These happen continuously in various places all over the world, whose plumes are less than 100 metres (328 feet) high and produce no more than 10,000 cubic metres (353,000 cubic feet or so) of volcanic debris. At the other end, you have VEI 8 events, which produce at least 1,000 cubic kilometres (240 cubic miles) of fresh volcanic material, have plume heights of at least 20 kilometres (12.4 miles), and occur on timescales of 50,000 years or longer. VEI 8s are also sometimes referred to as supereruptions, which makes the volcanoes that produce them supervolcanoes – but these are probably not what you think they are.

The VEI, although useful, isn’t all-powerful. Each volcano erupts in a very different manner to any other, so two VEI 6 eruptions, for example, are likely to be fairly different. Certain volcanic eruptions can also produce strangely high plumes even if the eruption itself isn’t particularly explosive and can sustain said plume through heat transfer and sheer momentum (see: Eyjafjallajökull, 2010). Others can be incredibly effusive and produce a lot of volcanic material but have pretty insignificant plumes and take place on that scale not particularly often (see: Kīlauea, 2018).

Still, the index is a good general measure of the general “size” of an eruption. A VEI 7 is more likely to have environmental and societal effects than a VEI 2 – but not always. It’s very case specific.

What are SO₂ emissions?

Those yellow circles denote emissions of sulphur dioxide, the third-most common gas that escapes through volcanic eruptions. When it reacts with water and sunlight, it can turn into aerosols that reflect sunlight. If an eruption produces enough sulphur dioxide, it can cool parts of the world that said gas and its associated aerosols have essentially drifted over.

Don’t be fooled by naysayers online, though. Major eruptions can briefly and mildly cool the world, but these compounds fall out of the atmosphere within a few years, and the changes are rapidly reversed. Said cooling moments are also eclipsed by humanity’s prolific greenhouse gas emissions, which – as you may have noticed – are causing a dangerously rapid rise in global temperatures.

The concentration of SO₂ in the atmosphere is low, unlike (for example) water vapour and carbon dioxide, the two most commonly erupted gases. As explained in E3’s FAQ, this makes SO₂ easily detectable by satellites, which makes it (among other things) a good identifier of relatively remote volcanic eruptions.

What about CO₂ emissions?

Even though scientists are still narrowing down just how much volcanoes emit, it's abundantly clear that they cannot produce anywhere enough CO₂ fast enough to even get close to the amount we produce.

Some rather excitable eruptions can absolutely produce a lot of both of these gases, sure. Sometimes a hemisphere can go without a summer thanks to a hefty release of SO₂; sometimes a planet can suffer from mass extinction-causing climate change caused by a million-year-long eruption rife with CO₂. At present, though, humans are producing at least 100 times more of the latter than volcanoes do every single year. This dominates the anthropogenic climate signal by such a huge degree that volcanic eruptions and their various gases don’t really make a difference in the modern era.

You watch the world explode as a globe, too!

Global Volcanism Program

So, what’s up with that ring around the Pacific Ocean?

You can also probably spot that, like most earthquakes, most volcanic eruptions take place on a horseshoe-shaped ring around the Pacific Ocean. This is the so-called Ring of Fire, a conveniently shaped network of major tectonic boundaries that are continuously shifting around in very complex ways. Thanks to these behaviours, this part of the world is responsible for 75 percent of the world’s volcanoes and a staggering 90 percent of the planet’s earthquakes.

The underlying causes may be similar, but any eruptions that occur here happen independently of each other. There’s pretty much no evidence that volcanic eruptions can trigger other volcanic eruptions, although there’s an ongoing healthy debate as to whether earthquakes, in some circumstances, can initiate volcanic eruptions nearby.

Do more volcanic eruptions occur in certain years compared to others?

Nah. Although it may seem like there are more volcanic eruptions taking place today than ever before, that’s just because changes in how news is reported means that we are hearing more about eruptions than ever before. The rate of eruptions over time doesn’t change, and like I said earlier, there are (on average) 40 volcanoes erupting around the world at any single moment. Again, this is perfectly normal.

Are there any volcanic eruptions missing on the animation?

Most certainly, and that’s because the majority of eruptions take place underwater. Unless they are freakishly massive or they produce a lot of volcanic material that floats up to the surface and someone spots it, plenty of underwater eruptions take place all the time but they simply aren’t spotted by scientists. In fact, before 1990, not a single underwater eruption had been detected despite the fact that roughly four-out-of-five eruptions take place within the oceans.

Recent engineering advances and improvements in underwater detection efforts are starting to shift things in this respect. Every now and then, robotic vehicles are responsible for a new “deepest eruption ever” as they explore further and further into the murky, waterlogged unknown. Despite this, the world's oceans are still enormous, deep and dark entities, and monitoring the seafloor is expensive, takes time and – often – is prioritised far less than volcanoes that erupt on land and just so happen to be near human populations. Simply put, when it comes to underwater eruptions, volcanologists are still largely in the dark.

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