Summiting Etna: the Gate of Hell

My own expedition into Etna’s center

Jesper Sandberg


I have always been addicted to volcanoes, and that addiction has resulted in many volcanic visits over my last 27 years of life, and I have indeed made many volcanic visits. The highpoint of that was seeing the live lava flows at Kilauea: of course Kilauea (just like Hector and Chad) is my favorite volcano. But the first volcano to thrill my brain was Etna in Sicily and this was the first really active volcano that I visited as a kid. I became very thrilled as a child because of it and more Etna visits followed. It too has become one of my most favorite volcanoes. As a child, reaching Torre del Filosofo was enough for me, and we had a lot of fun visiting there in my childhood years. As I got older and more adult I learnt more and more about Etna and about what makes it unique. It is probably the most productive volcano that is not on a hotspot and it is in a very complicated geological setting. Reaching the summit was a goal since I was ten. It became a realistic plan in 2015 and in 2016 as a 21 year old, the conditions were ideal for it. Thanks to social media I planned to do it with just friends, so I organized a little expedition in 2016 where we did a summit attempt that summer and we were successful. It has been way too long now without a VC article on it. I thrive well in Sicily every time, and Etna is just the sweet sugar on top. Etna is the volcano that I visited the most times, so it is very special. In this post I will post most of the photos I took at Etna further down in the article.

Photo: Jesper Sandberg, ghastly hot Sicily evenings, incredible temperatures here

(Click on each photo to see it at higher resolution)

Travel to Sicily

Sicily is indeed a wonderful place, with stylish architecture, clear blue waters, good food, white chalk cliffs, and of course Etna. Sicily seems to combine the best of all Mediterranean things in one single perfect hole or spot. I packed one single bag; being an experienced Sicily summer traveller I take just light clothes for the lowlands and some jackets for Etna. From late June to October Sicily is very hot, winters are subtropical and mild. The tourist season runs almost all year except the cooler winter. Sicily is charming and old fashioned, indeed much more charming than the modernist nordic countries, especially my own home country where a lot of post 1950’s city public planning simply seems copied from the nearby Soviet Union, resulting in lifeless concrete jungles. The modern post 1980’s direction is hardly better in Scandinavia with ultra modernism and introduction of skyscrapers. While in my home country function rather than form is important, in the Mediterranean form rather than function is beautiful. In the Mediterranean they have never really accepted modernism and this is one reason Sicily is so beautifully charming. The charming natural and cultural environments in the Mediterranean inspired many 1800’s painters, and so began the modern tourist era. Most of my vacation trips as child and teenager have been in the Mediterranean with fantastic memories. In late summer it is even warmer than tropical temperatures at times, and it is quite near to me, so a European rarely needs to go anywhere else for sun, at least during the summer. The Mediterranean of course has enough volcanoes to satisfy, and you rarely need to go elsewhere even if Kilauea always provides an eruption. For me traveling to Etna is straight forward, giving us excellent time and no jet lag, and because it is so active there is always a possibility to see something, and especially so for a boat tour to Stromboli.

When I arrived in Sicily I was greeted with the familiar stylish brown-beige tones of the architecture of Catania and the huge familiar mass of Etna whose large shape lurked in the distant Sahara haze with a pink gas plume. Getting out from the airport in over 40 C heat was a huge challenge, inside it is cold, outside it is hot, so Catania was simply impossible to explore. Instead of that I took the rental car, driving around interesting sights. The rental car had been in the sun too much so opening it revealed an almost 80 C inferno as it was its own little greenhouse, instantly lethal for any imaginary dog or person stuck inside. The vehicle had to be cooled a lot before use, driven into shade. Thanks to the car AC it was possible to explore a little of the local area before driving up. I drove around the outskirts of Catania and had a look at some historical sights like the lava elephant and the fortress that the disastrous 1669 lava flows flowed against. My interests then turned towards the 1669 flows themselves, which because of the dry climate were not fully forested yet. The sclerophyll vegetation had to be pushed aside revealing the surfaces of the lava flows and even lava tubes that formed in the last phase of that catastrophic eruption. Monte Rossi, the 1669 cone, was also visible in the haze. There are still islands of greenery among the barren lava flows. The warm sunny Sicily climate and Etna’s soils suit agriculture very well, so I took the opportunity to buy some of the local wines and olive oils that I would feast on the evening after the hike. After buying these I headed up straight to Etna to get away from the icky lowland heat that was becoming more oppressive every minute with every shop stop outside.

When you drive up towards Etna the dry mediterranean vegetation flys by with its aromatic smells and a wildfire here and there as well, and the ear ringing sounds of the cicadas shooting by. I drive up the way that has a view of the 2001 lava flow that stopped only 4 km from the town of Belpasso. The ghastly hot lowland heat gets replaced by cooler more bearable mountain air and the road snakes its way up Etna. Already many km in the distance, before I arrive you can see the south side ski area, the Rifugio Sapienza and the many other facilities they have there. Huge Aa flows dot the side of the roads and I drive past the alpine-looking building towards another hotel. I had booked a few nights at the Corsaro Hotel at Etna and a few in the lowlands later at Giardini Naxos. The hotel nights up at Etna were crucial for our expedition planning. My friends knew I was coming, and so the expedition to Etna’s summit was made. Before sleep I spent the first day exploring the ski area and the 1983’s lava flows that are just outside Hotel Corsaro which have some rough pahoehoes. With my dinner done, and the sun sinking below Etna, the conditions were set for tomorrow’s adventure.

The long climb up

Photo: Jesper Sandberg, the team overlooking Valle del Bove

Photo: Jesper Sandberg, my team in front of the Lagehtto cone that formed in 2001

The climb began early in the morning as I woke up at 8 am and first did the hotel breakfast. A hotel as fine as the Corsaro Hotel had excellent Italian quality food. Soon after Fernando Meschino, Vito Uva and Walter Contarino arrived at the parking lot outside the hotel, my internet friends or perhaps even strangers greeted me. We were to do the entire adventure on foot, skipping the cable car as that would be seen as cheating. We were to take the bulldozed pathways up the 2000’s lava flows and up to the charred summit plain and later up towards Bocca Nuova at Etna’s summit.

The four of us first walked to Rifugio Sapienza, the large Etnean ski base that resembles an Alp hut, to pick up food and lots of water as it was very hot despite the altitude. Rifugio Sapienza, just like Corsaro, is a pretty good hotel that offers good food and sleep accommodations and is one of countless tourist facilities here. I bought food here as the hike would be a long one. The huge Aa flows from the 2000’s are all around it. As you hike up the ski trails the Monte Silvestri flank craters and parking lots get further and further behind you. The lowlands was a furnace and even at the cooler altitudes at the ski area it was hot and uncomfortable in summer. The total climb up and back to Etna’s summit in the bird’s way (as the crow flies) is just 11 km, but because the winding gravel pathways up which zig zags and snakes its way up, the real length we walked that day was perhaps closer to 30 kilometers, combined up and back. During such a long hike water is essential, and we brought a lot; without it you could collapse, leaving you in the worst case alone on the slopes in the night to die and help may not arrive for some time. We started with clothes in the bags, but because it was unusually warm even up here none of that was needed, and the hiking generated great amounts of body heat.

Climbing was surprisingly easy as the paths up are well maintained by machinery and any new lava flows are often digged away, but at Etna’s summit stuff is much less certain as frequent paroxymal eruptions and small fissure eruptions often covers the gravel parts with Aa lava and that lava is an almost impossible terrain to climb over the scoria clinkers. At the time of climbing we were in luck as the summit had been relatively quiet in terms of large eruptions, with the December 2015 and May 2016’s paroxysms the only large eruptions just before the climb, and they had not sent any lava flows down the paths. Just one year later in 2017 our pathways to the summit craters was buried by the upper lava flank eruption of that year, making it impossible to access Etna’s summit from the south side. The first recent cone you pass on the way up is the 2001 cone, that sent lava down towards Belpasso, it is accessible right by the parking lot, a few 100 meters from it.

The climb up is not hard unless the paths are blocked by new lava flows. Me and the team of friends carefully made our way up the bulldozed pathways under the ski cable lifts. You pass huge viscous basaltic Aa lava flows of slightly evolved mildly alkaline basaltic composition from the early 2000’s and the gas plume from Etna’s summit was seen drifting off towards the direction of the alps. One of the weather worries was always that the cumulus clouds would build up because of Etna’s strong daytime summer heating, robbing us of visibility, but thanks to the hot dry Sahara airmass that dominated summer weather in Sicily the visibility was very good and weather remained fine. But cumulus can be a problem even in the summer season at Etna so you want the hottest dry desert airmass for hiking weather. Winter hiking is almost impossible because of cold and bad visibility and therefore potential eruptions would pose an even greater danger. In the winter you can ski down these slopes, doing it in just a few 10 minutes on the way back. In 1980’s and early 2000’s eruptions caused severe damage at the south side ski centers, destroying the ski systems, with the 1980’s flows being recorded by Maurice and Katia Kraffts, with lava bulldozing the rebuild buildings that we had slept in.

At almost 2500 meters myself and the determined team passed the dark crisp shape of Piano Del Lago scoria cinder cones which formed in 2001 and were visited by myself in the early 2000’s as a 7 year old with parents, with brother burning his hand there in a hot steam vent. Now more than ten years later, it was no longer steaming. Below Piano Del Lago craters is the even much more stunning Laghetto cinder cone that we also passed. It also formed in 2001, with huge lava bubble bursts and strombolian explosions. At time of this hiking I was 21 and determined to reach the summit and the goal was set, and this time I wouldn’t fail like the previous year in 2015. The team of 4 loaded up on water with the summit craters in view at Torre Del Filosofo area where a building was constructed and later buried in the 2001 eruption. Geoff Mackeley used it when he filmed the 2001 eruption avoiding falling bombs and scoria. The whole south facing area just below the summit craters of Etna is named ”Torre Del Filosofo” meaning the philosopher’s tower, named after the philosopher Empedocles who is said to have killed himself by jumping into the fiery chasms at Etna’s summit, burning up like Gollum, with the volcano said suffering indigestion and spitting out his sandals. This area had stunning phreatomagmatic action in 2002.

At Torre Del Filosofo we made a rest among solar warmed heaps of trachybasaltic scoria and lapilli before pushing into the summit. I also inspected the NSEC crater complex that was in the distance, it had grown enormously since my first Etna visit as child, and half of it was not there before 2012 even. This area is the last sight of Etna most persons unfortunately see, as most never push to the summit, either because it is closed due to activity or because the kids are too young, or because they are too old to climb it. With no eruptions and clear weather and young age the timing was perfect to do it. The walk up to here took about 2 hours if I remember correctly, and must done carefully and slow to avoid tiring. Slowly I make my way through the lapilli ash with Fernando first and in a little depression in the distance, I see something white. As I get closer the sight resolution gets better and what looks like a mineral deposit, a touch reveals the cold signature of snow turning wet on my warm finger. Lava and lava sand is a good insulator, so snow can survive the summer here hidden under an insulating blanket. In other words it never gets that warm up here, and some other Etnean lava tubes are permanent ice chillers as lava retains heat and cold well. I was more and more thrilled the further up we got, and I been seeking it for a long time, even if I been on Etna many times, but now with previous limits behind me it was a blast.

The path to the summit

Photo: Jesper Sandberg, Bocca Nuova steaming

Photo: Jesper Sandberg

Photo: Jesper Sandberg, These lava bombs caught my attention, clearly more fluid materials than most other of the materials I saw during my hike. Perhaps it was fresher deeper materials than the usual Etnean trachybasalt. Sadly I did not take a sample.

After the rest me and the friends left the doomed philosopher’s area and headed north west to a small gate hanged with ropes. In the background is the summit crater complex steaming, the gate was open and no police guards where present either, thanks to SEC s south east craters paroxysms with all recent lava flows at that date had flown into Valle Del Bove, meaning the summit craters area was not clogged up with frequent lava flows. The trail from there is narrower and passes through older lava flows and I was able to see the flow core of the Aa flows with the rubble on top and on top of that was scoria and lapilli. The excitement was high because now I finally passed the point where I could go no further as a small child. The weather was excellent and Bocca Nuova’s cone was right ahead me, it also hosts the Voragine crater inside. Very few Etna hikers were seen that day, perhaps they actually get too warm even up here at almost 3000 m. Usually the weather up here is almost polar for most of the year, Etna is a cold highland in a searing hot subtropical summer lowland. Just before heading up the central crater cone, we made another pit stop gorging ourselves on water and fruits, and the loose lapilli regolith was solar warmed as well. Because of the thinner air it felt warm in the sun, but noticeable cold in the shadow. Despite the lowering air pressure I was not tired at all, I guess that starts at over 4000 m for healthy younger individuals. Our ascent was quite impressive in speed despite Etna being an extreme altitude peak, probably driven by our excitement.

The landscapes appearance and features at Etna tell about the eruption styles and magmatic nature of the volcano. All Etnean landscapes that I visited on this and earlier visits before have all featured lots of loose materials, lapilli, scoria and ash sand and rubbly Aa lava flows. Even the thin near-vent flows where generally rubbly, and if any pahoehoe near tubes was present it was always rather large ropes and rough in texture. That instantly suggests that Etnean lavas are more viscous than the typical fresh lavas that you find in Iceland and Hawaii. Etna produces a crystal rich evolved trachybasalt, while low in silica, it is a very crystal rich melt and is a bit lower in temperatures than Hawaii. Still Etna is a relatively low viscosity lava. But these specs makes Etnean basalts far more viscous than Hawaii, and added viscosity together with Etna’s very high gas content, prone to very tall lava fountains indeed. Because of that, copious production of scoria, lapilli and tephra, and Aa formation even close to the vent is certain with added viscosity. It is this which is the cause of the copious amounts of loose lapilli materials that we had on the hike up.

The landscapes were smooth and very lunar like, with the loose lapilli could be taken for lunar regolith and smooth phreatomagmatic craters could be imagined as impact craters. The landscapes just below the summit craters were soft, smooth and sandy and dark grey. The smooth ash desert was littered with a few larger darker scoria clumps. Etna’s volcanic forms is very different from the smooth more fluid lava flows of Hawaii that was quite easy for me to walk on. Etnean terrain are either sandy or rubble lava that is impossible to walk on. Etnas lava viscosity is very variable, and seems to range from many 10 000 s Pa.s at Aa flow fronts to many 100 s of Pa.s at fluid spattering vents, which explains the variety of features seen that ranged from rough pahoehoe and spatter cones, to almost andesite thick basalt Aa flows feed by paroxysmal lava fountains. The average near vent viscosity at Etna seems to be perhaps 700 to 2000 Pa.s, with some Etnean flows almost in Hawaiian territory at least near the vents.The fluid Hawaiian flows for comparison range from as low as below 10 Pa.s to little over 100 Pa.s. Etnean mafic lavas are very crystal rich, and because of the high crystal content, the true melt viscosity is probably hiding behind the high crystal content. Etnean trachybasalts can be classified as hawaiites or mugearites depending on the ratio of potassium and sodium. They are similar to the Westman island lavas of the 1973 Heimeay eruption.

When the summit is accessible there are often tramped trails up there, so you don’t have to deal with the terrain, its very reminding of the paths up Mount Doom’s entrance that are maintained by Mordor’s slaves, I called it ”Saurons Road”. The last trail up to Bocca Nuova was not too hard although very steep, luckily no lava flows from lava fountains had been flowing there before our arrival, that would make the climb impossible. The four-man team made its way slowly up towards the central crater that hosts the Bocca Nuova and Voragine craters, it is a steep climb now but not impossibly steep, but sometimes you slip down the lapilli that is basically half a centimeter sized scoria chunks, overall the environment is incredibly sandy and the lapilli sand is coarse and abrasive and gets into the shoes. The whole team probably emptied our shoes 15 times during this expedition, the abrasive lava glass also wears down the shoes themselves, and the undersides would later melt in the heat, at least mine did. We also had to worry to not cause a landslide of scoria clumps as if they roll down and hit a person’s head, a person could be taken out. Foolishly we did not carry helmets or gas masks. As we approached Bocca Nuova at over 3000 m we gazed into the distance attempting to see Malta which can be visible as you can see 100’s of km on Etna’s summit. But the visibility was only 40 km at ground because of the Sahara summer heat haze or fog that was in the lowlands in summer. In other words the lowlands were smothered in a light brown fog, that made a brown horizon over the clearer upper atmosphere. Up here the skies where brilliant blue, and Etna’s huge gas plume was seen drifting away into the distance. Below the light grey mossy pahoehoe field of Bronte could be seen. As the team got closer and closer to the summit craters it got steeper and steeper and we were excited what we would see up there.

The cracks of doom: walking the summit of Etna

Photo: Jesper Sandberg, Fernando Meschino, Vito Uva and Walter Contarino at the summit

Photo: Jesper Sandberg. Fumarole features at Bocca Nuova

Photo: Jesper Sandberg. Fumarole features at Bocca Nuova

The excitement was great as we finally made our way, up the tramped non existent trail up Bocca Nuova. It was quite steep for the last part. Here the grey sandy lapilli landscapes began to change as dark lava bombs from the 2015 and 2016’s summit paroxysms littered the area. Close to the vents we were meet by new volcanic features. Many bombs had fluidal features, as close to the vents they don’t cool much at all. The last part up to the rim was littered by these splashed-out cow pie bombs, not as fluid as Hawaiis glassy splash, but they where clearly liquid when they landed and did look like dark splashed out cement or cow dung piles. These bombs were smooth and pahoehoe like, so the lava had very low viscosity, because of that, it could perhaps be fresh alkali basalt, rather than the typical trachybasalt that makes up the typical Etnean lavas. Such more fluid lava formed ground which was much easier to tread although more sharp. The materials was darker than the materials from vents below and probably was more mafic and primitive as the last eruptions before the climb, is said to have involved more gas rich primitive lava that made the gigantic 2015 winter Voragine fountain.

The four men team celebrated our ascent, and was greeted by heavy heavy volcanic fumes, yet somehow it was possible to breathe. SEC and NEWSEC and Central Crater that hosts Bocca Nuova and Voragine pits were degassing heavy and we were worried not be able to hike it and return down, but thanks to the wind the conditions at the summit of Etna became suitable for photography and we began to walk along the edge of Bocca Nuova and the results would not disappoint us.

Being inside Etna is one of the most intensely colorful and most amazing experiences that I ever had! The colors of the summit craters where surreal, condensed gases falling out minerals and sulfur. The colors where numerous shades of oranges, whites, yellows, beiges with fresher black bombs on it . I photographed all out at the summit. The experience was almost as surreal as seeing the active lava flows at Kilauea as I did 2 years before during a forest hike.

The 4-man team was amazed by the color, never before in my life had I seen so many fumaroles as this moment inside Etna’s summit. As we walked along Bocca Nouvas edge we were greeted by the most psychedelic display of volcanic gases and degassing, and as well as the great feel of having summited one of the world’s most active and productive volcanoes and one of the world’s most famous volcanoes as well, and it was the first time I was inside a volcano, even if I had seen eruptions before. The ground was harder and more solid now, yet very powdery with sulfur and stepping on lava and spatter had a crunchy sound.

The 4 person team continued our way along Bocca Nuova’s rim struck in awe by the beauty and color of the cooking hot landscape clad in sulfur. From every crack and hole in the ground there where volcanic gases coming out depositing colorful deposits of sulfur and minerals, so much that the entire ground was yellow or white or orange. There where so much volcanic gas coming out at the summit that we worried over out health being choked, but parts of the air had good quality despite the fumes. Still as we walk through the sulfurous fumes the whole place smelled strongly like fireworks, the brimstone fumes got right into the brain and the smell seemed to be stuck there for a while, and I thought it could not be good for my health. But we cancelled our attempt to tread Bocca Nuova’s interior even before the climb, as it was way too hot and noxious. There where fumaroles everywhere and some of the cracks where probably almost red hot if they were seen at night, especially those with orange sulfur. So we kept ourselves to the trail around the rim of the Bocca Nuova to avoid the most dangerous spots. Even there you had to watch out for deep cracks where a sinister glow could be seen, so the environment was treacherous. Bocca Nuova itself may not be as impressive as other basaltic pits and calderas, but still it felt huge. As we walked its rim coughing lightly, it was hard to grasp that only 48 years earlier it was born as a small glowing hole, and since then it had grown into an almost 400 m wide crater pit, now filled by Aa lava.

I gazed into Bocca Nuova which was filled by dark clastogenic lava flows from the huge fountains at Voragine just a few months before my visit. Some of its cracks where still feeling very hot when the wind blowed from there. The SEC and NEC craters were now hidden by large clouds of sulfur, their slopes yellow of sulfur with green patches of something perhaps like the Ionian pyrite deposits. The whole Bocca Nuova had been filled by the brim with new lava just months before, so it is perhaps better to call it a crusted-over lava pond, but it is far more viscous than the lava ponds in Hawaii. Two years after my visit this lava pond had began to shrink and contract as the lava slowly cooled. It was refilled in the 2020’s when Voragine became very active. Later in 2021, more than 50 intense SEC paroxysms made the summit inaccessible. I enjoyed the scenery and indeed there was so much sulfur and so thick that you could perhaps ignite it, like at Ijen, it is obvious that the pooled lava was still degassing and was liquid at depth. The magma system itself is just a few 100 meters below.

We did our big food break at Bocca Nuova feasting on quality food and myself worrying that the heavy volcanic gases we sat in would spoil the the taste. Everything we had on us became yellow of sulfur and especially the shoes: we left yellow-white footprints in the gas deposits around the summit. Everyone ate as much as we could, with Fernando Meschino being especially hungry. Everyone on the team sat beside steaming Aa clinkers that were yellow-green of gas condensates. It was a side seat in view of armageddon. The weather was good except the annoying gases, sitting on ground that was 20 years younger than myself was a thrilling fact, here the Earth is alive. The ground was very hot in some places, with one gas vent at a place in the clastogenic flow was almost hot enough to ignite a serviette, it darkened to brown, but did not ignite. It suggested at least 380 C, the thick ponded lava in Bocca Nuova was certainly liquid at least at some depth.

The gas production was noticeable, In fact Etna’s summit as a whole reminded me of Ijen because of all the sulfur. With such copious sulfur gas production its a sure sign of an open magmatic conduit system and of a well developed shallow magma storage at Etna, where magma sits and degasses itself. The copious gas amounts also has to do with Etna’s rather large magma supply and its alkaline chemistry, with alkaline magmas being more gassy than non alkaline ones. An average person with some geological knowledge may take all the fumes we saw as ”toxic gas” but most what comes out from Etna’s summit is just magmatic water vapour. But this magmatic water gas can be lethal too, and me and the team had to run from suffocating pockets. While sitting down resting, we enjoyed the warm ground, trying to avoid the hottest fumaroles, and warming ourselves in the sun, still every wind brought a strong chill here. Mostly the winds brought the same firework-like smell from Etna’s center, but drifting through the noxious fumes came another smell. an acrid burnt smell of rubber and plastic. I instantly jumped up and looked at my burnt shoes bottoms, luckily they where still usable. I realised that most coloured ground areas could not be sit on trustfully, but many of the fumaroles where also just warm and humid and not extremely hot. These fumaroles all felt humid as a hand swept through the gas, a clear sign of the water rich nature of magma, and I tried to avoid low lying areas in chase of gas pockets. If you tripped and fell inside here, you may never wake up again.

Etna is one of the world’s most active volcanoes and rarely goes a few months without eruptions during phases of high supply rates, so we where not safe at all as we continued to walk along Bocca Nuova’s rim. At any time an eruption could emerge which was a very unsettling thought that everyone had as the eyes gazed through heavy corrosive fumaroles looking at the sickly twisted landscape. While Etna is a ”red volcano” meaning the eruptions are not super violent because of the relatively low magmatic viscosity, the paroxysmal eruptions are still incredibly powerful often doing the world’s tallest lava fountains, so because of that it is always risky to be here. Small scale summit activity is nothing to worry about, it was in fact wanted, we had hoped for small scale strombolian spattering when we climbed up, such as had built a little spatter scoria heap in Voragine just weeks before my arrival and was clearly still hot enough to not allow sulfur to settle on it.

But large scale paroxysms are another thing definitely, such can involve glowing lava fountains 2500 m tall or more and tephra columns that go all way to the tropopause, showering the whole Etna area with lapilli stones. Had such an eruption broken out as we had lunch at Bocca Nuova’s rim we would have been in serious trouble, showered by hot lava chunks and perhaps directly killed by falling meter sized molten lava chunks. Survival chances at Etna’s summit during a paroxysm or subplinian fountaining are slim. But we were not very worried as a large eruption is often almost always preceded by instrument tremor, and should tremor rise, we would escape the area instantly. Still there was no good or perfect survival plan in the worst case scenario. Here in the heart of Etna or Orodruin if you wants to call it that, we are in the hands of forces of nature. Because of the potential hazards with eruptions, some in the team including me spent time every now and then looking at the INGV tremor graphs in case activity would arrive and if we should evacuate, in other words the mountain is more in charge of us, than we are in charge of ourselves, that is how it is to walk the depths of a hyperactive volcano. The others in the team were essential in this toxic, noxious, almost evil landscape, if I would fall or get hurt. They would perhaps be able to call for help and perhaps even able drag me out, although a large eruption is another thing as I said. No activity was seen during our hours at the summit, but the days after at the hotel NSEC did some small ash burps. Every team member’s ears and eyes were in high gear, in case Etna would betray us.

Our hike along Bocca Nuova continued after the food stop, and Etna’s west side could be seen. Here I attempted to see Stromboli only 116 km away, but it too was hidden under a martian like layer of Sahara dust and sea humidity in the lower atmosphere. The place from where the town of Bronte can be seen from Bocca Nuova, is the location where the lava flow that filled Bocca Nuova had spilled over and flowed a few km down Etna’s west side during the May 2016 paroxysm. Here the trail stopped, blocked by the lava flow. Reaching NEC, Etna’s highest point would mean more hiking through the poison fumes and potentially dangerous concentrations of volcanic water vapour so that possibility was not on the menu and indeed just visiting Bocca Nuova was fantastic enough.

The scenery at the summit of Etna was was incredibly dramatic, and very much is why I wanted to write this article and upload my photos. In terms of landscapes it is the most dramatic and colorful that I have ever had, very unsettling and dark, it really makes the mind go into hyperdrive. Every inch of Etna’s summit was belching gases and had colorful condensation deposits everywhere, with the dark basalt and sulfur and the fumaroles giving a really ”end of the world look”. In terms of aesthetics Etna’s summit was pure Mordor or the biblical version of hell. As the group of friends walked the rim images of Mordor came to mind, the sights were incredibly moody, dark, and satanic and almost goth metal, but a dark high fantasy like Mordor came mostly into mind, with Etna being Orodruin or Mount Doom as it is also called, being the feared volcano in Tolkien’s Legendarium. When my friends stood on outcrops surrounded by the sulfur rich steam, it was when the cracks of doom ”sammath naur”, the volcanic fissure at Orodruin where the ring was forged most of all came into my mind and a terrified almost paralysed Frodo not sure if he wants to throw the ring in. I also always imagined Gollum unseen stalking us in the acrid fog when we walked along the summit crater’s rim, and my mind playing with Gollum attacking the team leader Vito Uva who was barely visible in the fumes, with the enraged creature that emerged through the gas, trying to grab the ring that he did not have with him. Neither Gollum, orcs or any other complex life or life at all other than humans, was seen in this toxic almost sinister environment and birds avoid it with their sensitivity to sulfur gas.

The doomsday scenery we found up there must have had an impact on earlier explorers as well. The Romans and Greeks where fascinated by it and created a mythology about Etna. In the Middle Ages such unsettling sights of sulfur and steam at Etna were explained as the Gates of Hell, and this volcano became just as feared as Hekla among biblical scholars in the Middle Ages, in fact more so as the fires of Etna where far more frequent. In the early middle ages during Islamic Sicily it is calledجبل النارJabal al-Nār (‘the Mountain of Fire’), a fitting name for such a scenery that we experienced up here. I and the team spend a few hours walking the summit craters in this sinister netherworld between the skies above and the inferno below us, before we decided that the conditions up here where too dangerous and too untrusty in potential possible situations for our own safety, so we slowly made our way back downslope doing it all again but in reverse. With the ascent of Etna’s summit, one of my childhood goals was completed as I have been on Etna many times. More photos below follow here including the summary.

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Jesper Sandberg, Vito Uva, Walter Contarino and Fernando Meschino take aim at Booca Nuova

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Jesper Sandberg, Walter Contarino takes aim with the camera

Photo: Walter Contarino, silly zoomed in view of myself working my camera

Photo: Jesper Sandberg

Photo: Jesper Sandberg

Photo: Walter Contarino, Fernando posing in front of the SEC cone


Visiting an active volcano can be an extraordinary experience, and as a 21 years old I finally summited Etna’s summit, something that had been on the mind since childhood. It is an experience that really plays with the mind and inspires deep thoughts. Whether you can summit Etna depends on the conditions and levels of activity and if the volcano is open for visitors. While I have been on many volcanoes and even seen eruptions, this adventure was almost as exciting as seeing the flowing lava at Kilauea. Etna provides her own unique peculiar experiences and colors, and one of my goals was completed.

I also wish to give huge thanks to Vito Uva, Walter Contarino and Fernando Meschino for making this rather risky adventure possible; it would have been far too dangerous for me to go to Etna’s summit alone. There have been as many as four Etna visits since then for me, but the later ones without a summit ascent.

Jesper Sandberg, June 2023

Photo: Jesper Sandberg

196 thoughts on “Summiting Etna: the Gate of Hell

  1. A New post is up! Into the center of Orodruin

    Adim add my name to the last photo and as well add at the ending of the article ”Jesper Sandberg June 2023 ”

  2. Thanks for taking us along. A year ago this month this 80 yo managed to hike to Vesuvius’ summit. As for Etna, Crateri Silvestri served, as did Nea Kameni in Santorini’s caldera. June last, Etna was not in the mood for summit visitors and there did not appear much interest to that effect. Diamond Head in 2018. Haleakala in 2003. Those items on the bucket list checked. Whakaari was on that list, literally for decades as well, Providence has seen to it that I missed that boat . Never got close. Arm chair summits to Everest, K2, Annapurna, and Matterhorn have had to serve. Though I wouldn’t mind getting back to Halemau’ma’u after these past 20 years. Such is life.

    • I am impressed: not bad for an 80-year old. Vesuvius is not a long climb but quite steep

      • I could’ve hiked up Hekla this past November but chose an adjacent high vantage point to see the volcano up close and with elevation without actually being on it.

        I genuinely don’t think I would be able to summit an active volcano, especially with my wife in tow. I think it’s the feeling of there being too much potential energy beneath my feet or something.

        I give you guys credit though, wow. And Jesper hiking up Etna is no joke, that’s actually a pretty big altitude gain. Some people will start to feel effects at its elevation.

        • I guess our hike up Fagradalsfjall counts as an active volcano, so I can’t quite fully make the statement that I wouldn’t hike up an active volcano. I think I just meant any with a temper problem.

          • You can drive to the top of Kilauea 🙂 but then it is so big that even being on the edge of the caldera feels a long way from the lava.

            To be honest, the volcanic hazard is probably 0.1% of the danger of climbing Hekla, the rest is the weather, it is a tall mountain with no cover in the Arctic after all… Hekla has notoriety because it has erupted without alerting the instruments but most volcanoes will erupt without warning you in person. Kilauea was shaking for a month before it erupted recently, but the only quake in that whole sequence you would feel was less than an hour before it erupted… 🙂

  3. Very interesting, Etna is in some ways a lot more interesting than Hawaii. Kilauea has its lava lakes and the immense size of the island is clear, but now that Pu’u O’o isnt flowing you can only see the lake fro ma distance, and nowdays it seems it might not actually be visible as often as hoped.
    Etna isnt quite as active but when it is then it really puts on a show. And it seems to be doing something historically uncommon because I am not aware of anything even slightly comparable to the 2021 sequence in the past few centuries at least, that year erupted probably almost 0.5 km3 of lava and tephra, maybe 0.15 km3 DRE, which is probably the most of any year since 1669. It is very hard to find any numbers though, but there were at least 52 paroxysms in 2021 and some of the first have lava volumes of about 3 million m3, and all were very violent and probably produced a lot more tephra than lava. So 8 million x 53 is 424 million 🙂

    The yellow of the sulfur against the dark brown base rock and the white snow is striking, and really comes through on the photos 🙂

    • Snow ? Its all sulfur : ) its the height of summer during an African heatwave so No snow on the surface. Yes it was very exciting .. is the fluid looking Bomb more fluid than normal for Etna?

      • There was white that I thought was snow, although now looking at it again it definitely looks more like mineral crystals than snow, maybe gypsum or some other sulfate. Sulfur is pretty yellow always though, the normal stuff is S8 which is like a ring of 8 sulfur atoms. There are a lot of other allotropes of sulfur but all of the ones that are stable are still yellow, liquid sulfur is red though, and burns with an intense blue light as you know 🙂

        The lava bombs look like pretty typical frothy lava bombs, the lava from the paroxysms is probably very fluid but also very gas rich so erupts violently. I remember reading something about the same thing happening at Stromboli. Probably the viscosity of trachybasalt melt is very low, Etna is generally pretty crystal rich and still the lava flows pretty easily, if a really wide conduit could form perhaps analogous to the one in Nyiragongo then a similar lava lake could be created as the crystals settle out. I couldnt find any exact numbers but apparently the magma erupted during strong paroxysms is much less crystaline than normal, it is probably very fluid and likely hotter too.
        The first fountain of 2021 was much more hawaiian style than later eruptions, maybe it was crystal poor magma sitting in the conduit that got blown out, it wasnt super fluid like Hawaii but then if it was sitting around then that makes sense. Also that lava cools falling through the air in a fountain…

    • Etna is probaly masking its true viscosity behind its high crystal content, the melt glass viscosity is very low I guess, and the eruption temperatures that are up to 1140 C so is not far behind Hawaiis eruption temperatures ( Hawaii is generaly a bit hotter ) and Etna is around 1120 C in general. Temperatures are an enormous moderator of viscosity as that moderates the Sio2 polymerisation.. Etna is low in Sio2 as well.

      But because Etna and Stromboli are evolved mafic melts, their crystal contents is high so yes like grained concrete being erupted, below is some microscopy of Etnean hawaiite basalt showing its crystal rich nature, and one reason Etna is so prone to Aa formation as well. Shiney fluid glass surface lava flow skinns dont exist on Etna because of this high phenocryst content

  4. Fantastic account. I love those orange sulphur fumaroles.

    Etna is a fascinating volcano. It’s not super-big, but it’s very young. Most of the volcano has grown in the last 60,000 years, if I remember right. It can do a variety of eruption styles, long-lived flank eruptions that create massive fields of pahoehoe lava, violent flank eruptions like 1669, repetitive summit paroxysms, low level strombolian bursts, and even plinian eruptions.

    • Yes it was amazing.. and is one of many of my fav volcanoes, and very productive at current for being a volcano on continetal crust

    • Etna has a volume of about 380 km3, so maybe 300 km3 of that being under 60ka, gives 5 million m3/year, or 0.5 km3 a century. But the measured number recently is 25 million m3/year, 2.5 km3 a century, so something has changed drastically at some point.

      I found some numbers for 2021, I was a little optimistic earlier as the paroxysms were around 3-4 million m3 including tephra which was actually the minor part. So the volume for 2021 was about 150-200 million m3 of lava and tephra. This is still huge, most eruptions are well under 100 million. The 2001 and 2002 eruptions combined are a bit larger, but were two separate eruptions from the same dike. The 1991 eruption was more voluminous but lasted years. Etna in the 21st century has been mostly summit dominated but is a much more active volcano than it has been for a long time…

      • Yes, that is how much is thought to have been erupted in the past 60,000 years apparently, about 290 km3. Which is 0.15 m3/s if I calculated it right. This is only about a tenth of the 1.26 m3/s eruption rate of the past several decades. So yes, the difference is striking.

        • Although eruption rates were as low as 0.03 m3/s between 1670 and 1755. Rates seem to change by at least a factor of 50, being highest in the 1600-1670 period.

        • The thing that is different though is the 17th century had many flank eruptions that were of very large volume, and usually long lived making big lava fields or satellitic shields on the flank. Some also made or began with long lava flows that moved far from the vent, longer than most recent eruptions have reached since. The 1669 eruption seems to have been like 2001 but because it was so far down it drained out the whole volcano, it was not unlike Holuhraun, but it was way too explosive to be only summit magma, there must have been an eccentric dike too that rifted the whole south side of the volcano.

          Fountains like recently arent reported much early on, maybe there was an open summit vent in the 17th century, perhaps with a lava lake. It would explain why the summit collapsed in 1669, which sounds a lot like the smaller summit collapses of Kilauea, like 1924 or 1960, or the start of 2018 when it was ashy.

      • […] it is quite impressive about the volume rates of Etna in comparison to any of the other volcanoes in the Mediterranean.

        a minor dragon removed rest of comment on request of commenter

        • Remove this reply. Made a bit of a grave mistake. I thought it said 0.5 km³ per year, but it’s 0.5 km³ a CENTURY. My apologies, kinda overlooked that.

    • Overall, the volcanism in the area of Sicily and the Tyrrhenian Sea is impressive. The nine Aeolian volcanoes themselves amount to about 1800 km3, by my own estimates, erupted in the past 1 million years. Ustica and Drepano submarine shield volcanoes north of Sicily have some 2100 km3, erupted in the past 5 million years, although now dead. And Marsili and Palinuro submarine volcanoes add to possibly 600 km3 in 1 million years.

      • Do you get the numbers from the volumes of the volcanoes? That gives a good estimate for the magma production, but not all may have made to the surface. Internal magma chambers also contribute to the volume

        • It’s complicated. I actually got those numbers from a gravity anomaly map in Google Earth. By using a simple layer model for the gravity anomaly made by the volcanoes, assuming an average continental crust density, and using a correction when submarine. Some of the volume estimates that I have obtained that way are not too far from volumes quoted in literature.

          Yes, some magma is likely to have stalled in the crust, since most of these volcanoes erupt variably evolved melts.

    • The older days with lower supply rates they had a pure Trachyte Etna with explosive eruptions and caldera formations as the magma system was staler when Etna was earlier in the Pleistocene. During the Ice Ages Etna towered Ice clad, above dry grasslands looking like chilean volcanoes I guess a bit, these low supply eras had some massive trachyte plinian eruptions as well.

      Had Etna been like this today .. there woud perhaps go 100 s of years between eruptions or many 1000 s, the volcano is less dangerous now in terms of eruptions, but frequent flank eruptions are a pest to the lowlands

  5. I used the hot lowland weather for my advantage, knowing that Etnas summit woud have more friendly in temperatures, Amazingly we coud be in t shirts up there all day along, with all other Etna visits I had at same month was colder near summit, Infact below 10 c but that hot July hike must have been well over 18 at summit during the hike week. Its quite certain also that Etna have quite cold nights, to allow buried snow in ash to survive the summer

    The low oxygen did not affect me, that only starts to become an issue above 4200 meters I guess, but the hike was probaly driven by pure excitment rather than pure strenght 😂

    • Walking up will have helped since it gives time to acclimatize to the different altitude. It is much worse when driving up. Still, adrenaline will have helped!

  6. Was there much trepidation amongst your group in going right up to the summit? It is kinda one of those volcanoes you don’t want to be stuck on when it’s erupting. Envious of your hike though.

    • Well just little over month before my visit it was last activity before I arrived

      • Well I was there in middle July I think so well over a month

    • It is a fascinating story but one that leaves safety concerns. After White Island, we look at volcano tourism a bit differently. They took care but explosions can come very suddenly. Lovely to read about, though

      • Thats right.. a very sinister place to visit, and we was not alone, there where other tour groups too and single climbers, everyone taking a risk I guess

      • I got great photos as well .. and likes the astetics.. very foreboding, we had a great time in Etnas mouth, and e chosed Bocca Nuova because SEC woud be too dangerous to climb into and yes the trails up where open for vistors

      • We meet a few others there too so yes the summit was open for visitors .. use good shoes and lots of water and fatty food ( cheese ) to keep going through souch long walk.

        I dont know how long I walked that day.. But certainly a .. few 10 s of km!

      • There is a small risk, but it’s not higher than city traffic.

      • Etna have its hazards But generaly alot safer than climbing into Popo that some of my mexican friends often does

        I woud not step into any volcanoes that displays truley ”grey volcanism” that misstake made the Kraffts as well, when they tired of the red volcanoes and they got killed by Unzen. Red Volcanoes are always the most pretty with glowing hot lava as well

        • You were good prepared and knew much about Etna’s Hazards. That’s adviced for volcano tourists. They should search for a minimum of volcano and hazard information to know what’s dangerous and what not.
          One thing what’s dangerous on Etna are the cold A’a rocks. They can be razor-sharp and can do heavy injuries if a hiker falls on them. Sometimes it is not the erupting part of the volcano which is dangerous, but the remains of older eruptions.

          Yes, red volcanoes are the more beautiful ones. Grey volcanoes can do impressive eruptions, but then you shouldn’t be there.

        • Yes Etna is extremely prone to Aa formation due to its added viscosity and crystal content, Impossible to walk on and you cut yourself up.
          Fresh smooth Halema’uma’u pahoehoe is just as sharp but in its surface, but smooth and easy to walk on

          We where lucky, the paths up was not covered in Aa lava and thats what made the summit ascent even possible. Aa is Impossible to walk on, even thin fluid As sheets are hard. Thick front Aa flows are not even possible to to climb up. But Etnas lapilli deserts are an sandy but easier walk and thats what we had on the way up.

        • Yes I knew the risks well, and knew that most paroxysms have a rather slow start But not all of them I judged the best I coud and probaly knew the risks as well as the team leader, but I was acually the leader, because I organized the expedition in the first place over FB.

          Etna was very familiar landscapes for me too, so I knew what was what and the behaviour of diffirent craters. The heavy gases where almost the biggest fear

        • I’m not sure if paroxysms are such a big risk, the buildup to paroxysms is usually gradual.

          The biggest danger at the summit craters is gas-driven explosions:

          “Virtually all cases of human fatalities at Etna are due to the fact that humans were in areas where they should not have been in that moment, like the nine tourists who were killed in September 1979 near Bocca Nuova by a vent-clearing phreatic explosion. That event had been preceded by similar phreatic explosions during the days before and was characteristic of the volcano’s summit crater behavior in a period after a flank eruption.”

          Sudden gas-driven explosions are one of the biggest threats to volcano tourists. Apparently, such explosions are very rare at Etna though, and happen after flank eruptions.

        • Wow forgot these anyway we did not thread the interior of Bocca Nouva in case of suffocating fumes

          • All in all Etna is a Strombolian volcano which usually does something like Stromboli, sometimes bigger and sometimes smaller. Everything else are “extraordinary eruptions” of Etna. Those get public attention, but are not the everyday life.

            Therefore the danger for sudden Strombolian explosions at the summit is a steady risk there, but not as reliable as on Stromboli.


    Monks at Bocca Nuova in 1968 when it was a gllowing hellhole, very much like Halema’uma’u was early in 2008. Was a gas vent, venting burning gases like hydrogen. This is very much like a real Sammath Naur, the most feared place in Middle Earth, where the ring was forged, and the only place it coud be destroyed

    Do some open conduit lava lakes start off like this? Halema’uma’u collapsed into the chamber revealing the magma to the surface, perhaps Etna coud do the same its lavas are probaly fluid enough for that, in 1999 it had a small lava lake in Bocca Nuova

    • That’s the way Halema’uma’u was born, also the way that Masaya lava lakes form. The ground collapses into a glowing pit, and bam, you have a lava lake, or long-lived strombolian vent.

  8. Wonderful. Thank you.

    The Med’s complex snarl of subduction, with multiple phases, probable plate ‘windows’ etc etc is fascinating.

    Even if the Eastern edge of Atlantic is trying to subduct off Gibraltar, it will be ‘geological time’ before old ‘wet’ oceanic plate gets deep enough to cook off and send juicy blobs towards surface, close off the Med again….

    FWIW, the potential for back-arc eruptions already exists, given those volcanic Med shoals with yoyo islands…

    • Mediterranean is probaly doomed soon in geology terms, when Gibraltar strait closes, the sea will quickly evaporate in the summer heat, leaving a km deep insanely hot salt desert. The Future Is Wild have a whole episode on that

      • I’m thinking about whether the sediment layers of former evaporations influence volcanism there. The sediment layer must be deep. There is a lot of limestone, evaporated gypsum and salt. All this contains a lot of Natrium and Calcium (alkali elements).

  9. Thank-you for letting us participate in your marvelous expedition on Etna, Jesper! Etna is volcanic Queen of Europe, both the highest volcanic cone and the most active one. Etna is as high as the highest Alpes mountains.

    Etna is a strombolian-hawaiian volcano. The major explosive eruptions 2001-2002 were still in VEI3 size and high-end Strombolian eruptions. Etna shows why VEI3 eruptions often have more beauty/aesthetics and complex volcanic phenomena than larger ones.
    The most liquid lava is erupted at low flank events like Monte Rosso. But they’re not Tholeiitic. Tholeiitic was the “precursor” in Etna’s place: When there was a bay, the first volcanic activity was pillow Tholeiitic lava. That’s in part the volcanic base of Etna. Later the real Etna got different magma, I don’t know why.

    • Thanks yes it was amazing! Yes Etna produced quite pure thoelitic mantle basalt 500 000 years ago, souch lavas woud have been hot and very fluid. The later more sillica undersaturated magmas where generated by difftent melt rates in the mantle.

      Some think Etnas magma source is below Malta today and the magma uses canals in the litosphere to get to Etna, the deep unseen magma of Etna is probaly a highly fluid alkaline basalt like Hualalai and evolves a little on the way up. Some of Etnas eruptions maybe called ”hawaiian” like spatter cones, lava tubes and so, But the lava is never really as fluid as Hawaii the real viscosity of Etnas current magmas are probaly hiding behind their very high crystal contents. Not even in the lava tubes here, does Etnean lava have a competely smooth surface

      • Etna belongs to the class of effusive volcanoes in subduction zones. Hector’s article on Popocatepetl showed that also Mexico has Basaltic volcanoes in the east. Also Cascade’s volcanoes have some basaltic ones. F.e. the Black Butte Crater Lava Field has basaltic shield volcanoes. Even Mount St. Helens has a past of basaltic eruptions, it is a volcano that changes magma from time to time.

        Indeed, Etna is not as fluid as Vesuvius. Vesuvius can easily erupt a Nyaragongo style alkali lava river and do an impressive Plinian plume the next time.

        The most active volcano of those we can visit now, is Vulcano. It ejects active Fumaroles, but usually not more. Other volcanoes are either too dangerous to visit or too dormant to see anything happening.

      • Yes Vesuvious is very fluid indeed, its a tephrite magma so more Sio2 undersaturated than Etna and are evolved from an ultrabasic basanitic magma, the 1929 activity had nice lava waves, looks almost Hawaiian

        The most fluid of all Italian lavas are probaly the lecucitic ultrabasic magmas of Coli Albani very Sio2 undersaturated, but so gas rich they generaly always blows up. Italian magmas are quite alot potassic / sodic so very difftent from other subduction zone magmas

        Still Hawaii maybe generaly
        The most fluid of all erupting magmas, despite being a Sio2 enriched thoelite it flows like ”liquid aluminium” at least at Halema’uma’u I guess at really high temperatures the Sio2 dont matter much at all, the overlook lava lake had specialy low viscosity watch here 11:01 – 11:10

        At high temperatures most magmas gets very runny I guess, but its rare for any erupting magma to go much above 1160 C with over 1200 C generaly seen only in Iceland and Hawaii.

        • If we look on Hawaii, the volcano which reminds to Etna most is Mauna Kea. Just imagine without the star observatories. Then you have a summit with several cones which look much like Etna’s summit cones. Activity can switch from cone to cone over time. The difference is that Mauna Kea’s summit cones are monogenetic. They are extinct, but new vents will pop up somewhere else (maybe after more 5,000 years).
          Mauna Kea also got the magma much directly from the mantle without a large chamber. So Etna resembles much to postshield Hotspot volcanoes and weak Hotspot volcanoes.

          • Erebus is quite similar too, while a bit more viscous perhaps, But very similar with being a stratovolcano built on and earlier shield and having filled earlier calderas and you gets a shape similar to Etna, Erebus does lack a valle del bove for comparsion and is far far more alkaline and less productive

        • I did find an article that looked at olivine in the Etna magma (there is some, just not a lot) and the deep source has a temperature of over 1250 C.

          • Woud make the deep Etna magma as fluid as Kilauea

            Kilauea itself is over 1700 C right ? and as liquid as water at depth

      • It is true that there are some taller volcanoes in Europe. But those volcanoes are not as active as Etna. If we combine the factors “height” and “activity” to a 2-dimensional-challenge, Etna is the Boss volcano of all present European volcanoes.

        The other volcanoes are either more dormant (Erebrus, Pico del Teide) or lower (Stromboli).

        • It’s the historical eruption rates of Etna that are so spectacular, its historical eruption rates have reached nearly 10 times higher that its 60,000 year long-term rate. In fact, in terms of the eruption rate for the past few decades, it beats Piton de la Fournaise. I think Etna might be well be the third most productive volcano in the world right now, after Kilauea and Nyamulagira.

          In terms of overall size, it’s not very impressive though, 500-600 km3. A lot of Anatolian volcanoes are larger, like Ararat, Aragats, Sahand, Sabalan, or the Ghegham Ridge, all the aforementioned having over 1000 km3. Canary Island volcanoes are much larger. La Palma has about 9000 km3 for example.

          • How can Etna get so much magma without a Hotspot plume below?

            If we include Iceland in the search for big European volcanoes, Öræfajökull is another tall and moderate active volcano. It only does big or nothing. Last times 1362 VEI5 and 1728 VEI4. Albert had an article about the eruption 1362 some years ago:


            The accumulated volume of both eruptions is very high. It may be the biggest + and most active Plinian volcano of Europe. Vesuvius is also Plinian, but not that often so large.

          • There was also Pico do Fogo in the Cape Verdes, from 1500 to 1761 (at least according to the Volcano Smithsonian), but I am quite curious if there are any hotspot stratovolcanoes that pretty much do the same thing as Etna.

      • There is decompression melting in the mantle caused by the Mediterranean tectonics and that fuels Etna Etna is rather deep magma so the source is way below the crust, Etna is some strange rift volcano and togther a subduction slab window.

  10. Kilauea rapidly inflating again. Looks like the vent is blocked for real, the show is over for now. But not for long probably. Inflation rate now of over 1 microradian a day, which is insanely fast, it makes the already very high pre-eruption inflation look like a flat line.

    • The “normal” thing is something like 6-8 microradians a month, this rate is extreme. I wouldn’t mind if it keeps going this way, but who knows what exactly is going on.

      • Most likely quite some margin of error, but the eruption that (probably) just ended erupted 9.1 million m3 of lava from 7/6 to 7/12, causing about 17 microradians of deflation. So very roughly the rate could be something like 560,000 m3 per microradian. By that metric the supply rate now is probably a similar number…

        560,000 m3/day is equivalent to about 205 million m3/year, or 6.5 m3/s. So about twice the rate of Pu’u O’o and probably a similar number to the hotspot generation as a whole. At this rate it will recover the volume of the last eruption in about 2-3 weeks. It would be very interesting to see an eruption break out that is entirely outside of the deep lake, without any dense lava to cap it. Even through the lava lake the last eruption managed a 200+ meter initial burst.

        Kilauea right now is being fed with magma at the same rate Etna was during its fireworks of 2021 🙂

        • Actually, I think I got the maths wrong. Kilauea before June had erupted about 165 million m3 of lava. On top of this there was about 1.5 meters of caldera extension, compared to 2.5 m of contraction in 2018, so we are theoretically 60% of the way recovered from that drain or about 700 million m3 all combined. 0.7 km3 in 5 years is about 0.14 km3 a year or 4.5 m3/s. The eruptions have been lower than this on average, September 2021 was closest at 3.5 m3/s.

          But what I didnt take into account before is that is the rate that is causing 8 microradian a month… 1 microradian a day is something like 4x as high as that, 18 m3/s, which is something like 570 million m3 a year equivalent… If this keeps up there isnt goign to be much left of the caldera in a couple years.

      • The situation looks very good for a New Puu Oo constantly effusion into the ocean.. If the lava can make it into the rift and form an open pathway

        • A SWRZ Puu Oo is possible, but it would be more explosive, because there is stored a lot of evolved magma …

          • Only if it is in the Kamakaia hills area, if it is somewhere else it will probably be pretty normal. Well, normal considering what is happening 🙂

          • Yes, if it is somewhere else, it may be normal (not evolved something). But if the new magma comes directly from the mantle, the first stage may be a bit alkali like Puu Oo early stages. I hope that we get some nice tall lava fountains. That’s something Etna and Kilauea have in common during their best days.

          • I think if an eruption can begin from a location that is outside of the deep laje, then we will get some very high fountains. The lava lake has degassed lava that is up to a few years old and even with that the start of the last eruption had a 200+ meter initial burst. And the wall vent was fountaining to some tens of meters with an effusion rate of probably 10-20 m3/s. The opening stage in the first hours was probably over 1000 m3/s, certainly in the hundreds.

            But the magma wants to break the least rock it can and that will make it keep erupting under the lake and promptly drown. So perhaps this is likely to continue.

            The one thing that is worrying us this is exactly what happened in 1959, the lava lake drowned the vent but because eruptions decompress the chamber the supply increases, and potentially by a lot. In 1959 there was net inflation during the eruption, which is what set off the eruption in Kapoho, which was only 5 years after another eruption in the same area. Usually LERZ eruptions are decades apart or longer.

            Not sure if the SWRZ can open far enough to behave the same way. So a shield forming on the SWRZ might cause the ERZ to become more active anyway.

          • We have to look at two different magmas: 1. The magma which since 2020 did summit eruptions and may soon expand to locations outside Halema’uma’u. 2. Possible new magma from Pahala and deep SWRZ that prepares new eruptions at middle/lower SWRZ locations.

            The 1959 Mauna Iki eruption didn’t begin in the crater (where previous lava lakes happened), but on the surrounding crater wall. Maybe the recent vent on the caldera wall of Halema’uma’u showed a similar development. Once a lava lake is too thick, new magma appears to get problems to cross it from base to surface. It need more and more Newtons to make the next eruption above the lava lake. The weight and density of the since 2020 fast growing lava may additionally change gravity and structure of the surrounding summit caldera system, so that new channels can open on new locations.

            The hot lava lake changes the surrounding lava/tephra rock. This metamorphosed (old) rock can behave different to cold rock. Maybe the dike that fed the vent on the wall went through metamorphosed rock below the lava lake. I’d suppose that next episode will be similar and avoid to cross the whole 400m deep lava lake but take the hot aged rock.

          • I think the deep Pahala magma has probably got a path, up thrpugh Kilauea the normal way. Lower SWRZ eruptions probably still only erupt from the summit although like LERZ eruptions the path taken is probably more complicated than a tube 3 km down. Although 1823 was literally a crack that was mostly above sea level, maybe the result of the south flank earthquake of that year, and the summit lake flooded out the hole. Seems somewhat unlikely to happen that way so soon after the 2018 quake but check back in a couple decades.

            But a lower SWRZ eruption that begins from the connector will probably behave very similar to a LERZ eruption, strong and maybe very high fountaining, and high effusion rate. But not as high as 1823. Seems an eruption like this in that area has not happened in the past 1000 years but there is a line of partly buried cinder cones near the Great Crack, so it has happened before at least once.


    Nice video on Etnas early 2000 s eruptions, showing how relativly fluid lava makes instantly large Aa flow, rough channels even close to the vents the high crystal content must be a factor here togther with the higher than pahoehoe eruption rates

  12. Hello! 🙂 Thank you for the AMAZING article Jesper! ♥
    Etna has been and always will be my favourite volcano and my forever love! <3 I love her big fountains, her explosivity, when she is going wild 😛 My favorite eruptions are- Voragine 03 12 2015, Sudest 10 02 2022, Sudest 23 02 2021, the most explosive of them all,it was wild watching them on webcam! I had visited Etna 3 times, but summit tours were forbidden, it was still amazing tho. She is faschinating and I'm looking forward to see what she is cooking now 🙂

    This is drawing of mine, I did it quite long time ago, the Voragine paroxysm of 03 12 2015 🙂

    • Should be some paroxysm again soon I guess, yes I made it to the summit of Etna a few years ago

  13. Excellent work Jesper! I really enjoyed reading it.

    I was there in July 2001 when it was erupting, but that was before I became really interested in volcanoes. I spent a few days in Catania and in the evening you could clearly see a lava fountain and the stream of lava coming down the slopes. We asked a local if it was possible to go up and watch the eruption, but were advised not to: “The place where the buses park is a crater now, you should not go there”. So we watched the show from a distance and enjoyed the local food and wine instead. One morning there was a thin layer of fine ash that covered the city. People were sweeping the ash from their cars like we sweep the snow from our cars in the winter. You got small amounts of ash everywhere – in your nose, mouth, ears, eyes. We probably should have had masks but didn’t realize that back then. It’s a nice memory, but today I regret that we didn’t at least try to get a bit closer to the action.

    • Fascinating! Yes the 2001 eruption thrilled me as a child as well as all the paroxysms before it. Saw that on TV with geoff mackeleys spectacular recordings. 2001 sent a lava flow towards belpasso before it stopped, souch 20 m thick Aa still steamed after winter rains in 2014 I think owning to the great insulation of the lava.

      Only Etna activity that I seen was small burps from NSEC

  14. Made this expedition years ago, so trying to remeber everything correctly

    • My biggest was not a volcanic expedition but a hike on one Norwegian glacier in March 2006: Hardangerjøkulen
      It is on the half way between Oslo and Bergen. There is the railway station “Finse” from where it’s a good walk or skitour, and in March it’s very Arctic landscape up there.

  15. RE :”Fascinating! Yes the 2001 eruption thrilled me as a child as well as all the paroxysms before it”. Yes,.”as a child”. I recall being hauled out of bed by my parents some 70+ years ago to watch a documentary on the birth of Paricutin. I was ‘gaga’ for volcanoes at a tender age as well. How the tourists flocked to Hawaii and Iceland in the recent past. Yet they are not rushing to the Philippines, and Whakaari spoke for itself, do we? Notwithstanding the romanticization of some of these events, this august body has never ignored their potentially disastrous and irreversible consequences to life, property, and environment.

    • Etna is usualy not a very dangerous volcano, but historicaly flank eruptions been very common so that destroys both farmlands and pepoles homes yes. 1981 was last time it was really bad, that one was 600 m3 a second and it reached the lowlands quickly, luckly for the populations around the activity been mostly summit based since I was born.

      Flank eruptions are not wanted at all really

    • Seems a likely case for another intrusion before the end of the year, if one of those swarms lasts for longer than a couple of hours it is game on 🙂

    • Katla’s been having a few the past week as well, looks like another ones happening today too.

      • Today Katla had a 3.6 earthquake at 0.1km depth, followed by a swarm of smaller earthquakes. Was it a hydrothermal event? Maybe the glacier hides some Geysirs which make hydrothermal explosions sometimes.

  16. Getting down into the lowlands after the summit was hard because of the heat, this was well into July so its like an oven outside. Even the nights where very hot perhaps 28 c. Sicily do get very hot as summer progress its close to Sahara desert, up to 48 – 50 C is possible in extreme heatwaves at day, and 36 – 40 c is an avarge hot Catania summer afternoon, with me having 44 c running around in the city trying to buy stuff the brain simply melts. Luckly extremely high temperatures is mostly a July, August, September and even early October thing, most of the other parts of the year Sicily is cool and pleasant and winter nights can even be really cold. The warm subtropical nights where memorable indeed, was as warm as Thailand If not even more.

    I have always visited Sicily during the hot summer months, and kind of getting the wrong view, its not t shirt weather in winter in general there. The Mediterranean stays pretty warm all way until december when the sea cools down, then with a cool sea its quite slow to warm, with being notable cool at coasts until end of June

    Etnas summit only have good weather in July and August and rarely is warm .. we had insane luck with our hike weather wise, good visibility and good ventilation of volcanic gases.

    • And gecko lizards running over my face at night when I sleep, as well as stinging ants and snakes the med is little Australian with all stinging animals althrough nothing like the toxic mess that Chad lives with

      I swimmed alot in the warm evening, looking at Etnas dark siluhette at the distance trying to make out a non existent glow that I imagined to be there 🙂 I coud spend hours in it and one hazy day there where a few small real ash burps from NSEC that I saw

  17. Very shallow swarms and some green stars at Katla the last week or so. Somewhat more than usual. A few deep quakes stand out. Anyone here who to interpret the drumplots?

  18. Very shallow swarms and some green stars at Katla the last week or so. Somewhat more than usual. A few deep quakes stand out. Anyone here who an interpret the drumplots?

  19. This march we visited Stromboli and Etna.

    Due to massive windes (~ 100km/h) we didn’t make it up to the crater, but we had a look at the crateri silvestri, and later after hitching a ride to the top of the funivia with the 4×4 bus also “summited” the Laghetto crater. The day after tht we hiked to the Serracozzo cave (sadly no video of that) and had a look into the valle de bove from Serrcozzo.

    here is a short video showing a bit of the scenery at Stromboli and Etna this spring:

    • Monte silvestri Craters where very memorable for me as a small child

  20. I was sometimes thinking about what Emporer Frederick II of Staufer dynasty thought about Etna. He was interested in science and philosophy of his age and resided in Palermo; so Etna should have catched his attention. Palermo is too far away from Etna to see something. But it must have been a topic on Sicily throughout all the ages.
    Etna changes very fast the shape of its summit and craters, that it’s hard to imagine how Etna looked like 1200-1250. Etna did an ocean entry 1224:

    • Ocean entires is on Etna pretty much happens only when you have a major flank formation cinder cone eruption or a fast fissure

      • Yes, those are the most geologically exciting eruptions there, when big and unsual things happen. But they have the disadvantage to heavily destroy towns and human life.

        Those fissures (also recent smaller ones) often have gassy magma/lava that like on La Palma has explosive Strombolian behaviour on higher parts of the fissure, but Hawaiian with lava channels behaviour towards lower parts.

  21. ?ssl=1


    Etnas 1981 eruption was scary stuff, No its not Mauna Loas 1000 s or even 10 000s of m3 a second, but still 600 m3 a second is very fast and woud reach the lowlands very quickly as 1981 did. Souch sudden and fast flank eruptions are the most unwanted Etna stuff I guess, because the lava flows a long way in short time. While not as fluid as Hawaii, the 1981 lava flows woud have still flowed incredibley fast near their vents and specialy so during the opening of the eruption, Etna too makes its own curtains of fire. This kinds of eruptions are the most unwanted and If 1981 broke down lower down it woud probaly have reached the ocean, Etnas lava despite added crystal viscosity flows very easly, so I guess the glass melt have really low viscosity

    • Yes the first part of that eruption that had viscous cold tephrite lava, so very Etnean with strombolian fountains and huge Aa flows Infact perhaps even more viscous than Etna

      The later phases of that La Palma eruption made very very fluid basanites so not very Etnean at all

      • There is a video of Tajogaite in the first day, the lava was always very fluid but at the start the fountains were huge and the fallout buried all the effusive vents. The cone also collapsed and flowed away as thick semisolid spatter flows a few times. But over time the vents became more efficient so some became gas jets and some became effusive.

        Probably the lava at the start was not quite as fluid as later on but it was still very free flowing. Tephrite and basantite are basically the same but basantite has more magnesium.

      • The Basanite was incredibley fluid .. they saied it was as fluid as Hawaii right? I read it had incredibley low viscosity

        • Actually that article said it was 10x lower viscosity than basalt based on their calculations of the flow speed and how the liquid behaved. At one point the lava was supposedly as fluid as hot olive oil and probably over 1200 C, although this was acknowleged as being extreme and most of the time it was a little more modest.

          But because basantite doesnt form crystals as easily as basalt and is lower in SiO2 it has a much lower viscosity at most temperatures. Probably lava erupted at a summit vent on Kilauea is similar, but the lava erupted at P’u O’o was not as fluid as the La Palma lava got at times. The La Palma eruptions began very deep, there was all the talk of Fagradalsfjall being pretty direct from 20 km but the main quakes under Cumbre Vieja were twice that depth and some deeper still. So a silica undersaturated magma with high gas content that is erupting basically right out of the mantle from 50 km down… not so surprising it was so fast.

          And then there is the sills under Pahala, that are also 40 km deep…

      • Yes Halema’uma’u have incredibley fluid lava, with the overlook lake made milimeters thick splash marks on its walls, I guess at really high temperatures the Sio2 dont matter much at all as seen in liquid iron slag with 60% Sio2 and flows like water.

        How hot was the 2008 – 2018 overlook lava lake? Was there any temperatures measurements? 1250 c ?
        The deep Kilauea magma maybe over 1600 C and as liquid as water, but thats for a depth of 150 km I guess

  22. Currently Kilauea has nearly no shallow quakes, most are accumulating at 25-35 km depth. There is a cluster of earthqaukes near Pahala, but at the same time there is a number of those earthquakes below SWRZ and the ocean to the south of SWRZ.
    While shallow earthquakes are nearly absent, inflation has become steeper today. It looks like Kilauea wants to do something before June is over …

    • Yes it is really shooting up, it makes the runup to the eruption look like a flat line. Currently it is going at over 1 microradian a day.

      I can only guess about the lack of shallow quakes but I think it is probably trying to reuse the dike from the last eruption. The lava lake has actually gone up by a meter in the past week, or at least the spot where the laser points has. So presumably some lava has gone into the lake but not enough to break the crust.

      It would be fun to see the wall vent become a lava geyser but it isnt degassing or anything, unfortunately I think it is dead. But its existence means magma is probably trying to erupt outside the lake and will use other faults to do so now. It wouldnt surprise me if vents open outside of Halemaumau in the next eruption, even if small or short lived.

      • RE: “It would be fun to see the wall vent become a lava geyser..” It is remotely possible to assume that there remains a patent conduit leading away from that vent or that the vent itself is patent. I would deem it choked.

        • Thats what I said, it isnt degassing so is probably closed off.

          My general idea with how the caldera is behaving is that the lake is so big now that the intrusions have to have immense pressure to happen now and will also be shut down easily. It is somewhat similar to how the Galapagos calderas behave, only those are much more mature.

          The intrusions are probably inclined cone sheets, even if they are near vertical any amount of inclination outwards would require the intrusion to lift the lava lake. If it was solid then things can fracture but the lake is liquid and this also will encourage intrusions to acrually erupt under the lake too, less rock to break that way. This of course drowns the vents anyway.

          So basically at this point there just isnt an easy way out of anywhere, so eruptions are probably going to be pretty frequent, short lived and intense. That is until one of the rifts gives in, and things might calm down a bit as eruptions go there and need to fill in space underground. And when that happens perhaps we get another Pu’u O’o 🙂

          This does all remind me of what happened after 1959 though, where a summit vebt existed but couldnt relieve the pressure, so it went down the rift. And it went down the entire thing too and started a major eruption, the crater floor now is only 100 meters lower than it was then, which isnt going to stop things for long, maybe a few years. And if the supply has surged by as much as I think it has then whatever timetable it was running on before has got 3-4x shorter…

          • I’d imagine that a possible next eruption can be a fissure eruption that runs from Halema’uma’u over the wall vent towards SWRZ. There are already cracks/faults, that should be vulnerable for rising magma. The last eruption showed this line from the wall vent towards the most northern vent inside the lava lake. This line only has to open further to southwest.

            A possible danger is, that next eruption will be accompanied or preceded by strong earthquakes. The present silence is suspicious.
            The beginning of the next eruption can also be explosive. If magma can’t release gas and steam before, it can push out the overlieing rock violently with an explosion.

          • The live stream webcam sometimes focusses on the cone on the SW wall. Behind it you can see the cliff. Above the cliff there is a white spot, it looks like sulfure. There might already exist some fumaroles which show weaknesses in the ground that can be used by magma.

          • DI events are temporary, and usually the trend that was going on before still happens. So the D part will just set the tilt back a few days followed at some point by a doubly fast I part. The DI events are probably a separate process to magma supply, maybe being caving in of the walls so being related to the magma chamber growing. Another alternative is that the chamber literally behaves like a lava lamp, with the D being when the top starts sinking.

            Most likely all of the ideas occur in some way. But basically the supply right now is very high, the magma chamber seems to be expanding, and the last two intrusions seem to have broken the ring fault formed in 2018.

          • Before the recent eruption in June there were no DI events, but a flat up and down of deformation.
            A real DI event has a flat inflation (often negative flection) followed by sudden steep deflation. The rise looks like the front of an orca until it goes abruptly down.
            Today the DI event didn’t have this perfect shape. But it may indicate some change somehow somewhere …

          • It seems a very short one. Sometimes they follow each other very quickly and do not leave time for a full recovery. Perhaps that is happening now? Wait and see.. The slow rise along the minimum is not related to the DI event but is the general inflation, I think. The dip just before the recovery phase is typical. Sometimes there is a bump just before the onset of a DI event but that did not happen this time.

      • Going back at least as far as 2007 (when I was last on Kilauea), there was a persistent fumarole at the intersection of Halemaumau and the SWRZ. Every photo taken of that area from then up until the 2018 collapse showed that same area degassing merrily away.

        As far as I can tell, the 2023 wall vent is in the same spot. Coincidence?

        • There is a fissure swarm that went from Kilauea Iki all the way down the SWRZ. Kilauea Iki itself might be a bit of its own thing, and the lower SWRZ is an area that is complicated, but Halemaumau to Mauna Iki is pretty well established. 1971 eruption opened the whole thing. Mauna Iki also opened the whole thing although lava only erupted at the ends.

          Probably the fumarole was shallow magma in the area. The west vent now might be a bit different because that shallow magma drained in 2018 but the weakness that made it form in that area is probably the same. The actual fissure orientation for the wall vent though was a circumferential orientation, so at least at the surface the dike didnt go into the rift. But that doesnt mean the next one wont.

          The SWRZ is a better place to have a flank eruption, no one lives there or anywhere that is considered at risk of an eruption there, unless something crazy happens like a tall fountain down near the coast that showers Pahala in tephra, or a tuff cone forming. Or a dike getting into the Kaoiki faults and erupting outside of the normal rift area, which has happened at least twice in the Holocene. But none of those has happened in millennia so chancesare pretty low. An eruption like 1974 but even a bit larger would be a sight to see, even at only a few hours long and 6 million m3, that eruption made a flow that made it 13 km. The eruption that just ended had a similar initial eruption rate, so if something breaks out on the SWRZ it could be in the ocean in hours.

    • It should remind us to watch all volcanoes on Vatnajökull. 2014-2015 we saw Bardarbunga with a great fissure eruption. Thortharhyrna (with English th), Kverkfjöll, Öræfajökull and Esjufjöll are waiting for their next eruption sooner or later. Of them Kverkfjöll has had the longest break until of the volcanoes. It last erupted 1300 years ago.

    • Quakes of this magnitude are not common at Þórðarhyrna. In fact, this was the largest quake recorded since measurements began here (previous largest was at M2.6).

  23. Anyone think Etna coud develop a Glacier If she grows even taller? Or perhaps she is too active and too hot at the summit for that I guess

    • Etna needed (conjunctive) Ice Age to get glaciers. It will collapse before it grows much higher than now. Etna had several collapses before and possible explosive eruption can fuel the instability. Mauna Kea has with the underlying former shield volcano structure a more stable base than Etna.

    • The whole east side of Etna is sliding slowly into the ocean I heard and rift eruption intrusions keeps pushing away the eastern ground

  24. I’m going to take the over on Katla being the next Iceland eruption.

    I fully anticipate being wrong, but I’m all in on Katla being in a pre-eruptive build up.

    I’m sure it’s much likelier that Reykjanes unzips again first, but you gotta take chances in life.

    • It should be noted that, although it is impressive with all the green stars, IMO considers this to be normal summer activity at Katla and the status stays at green. The cause is believed to be geothermal and activity usually increases during summer when the glacier is melting and melt water interacts with the geothermal heat.

      • Sooner or later Katla is determined to do anything, because it is one of Iceland’s most active volcanoes. But the next magmatic eruption can still wait for decades. Our digital cultural age is too unpatient to adapt to volcanic/geological timescales.

        • I do believe it’s going to go soonish, but of course ‘soon’ may still be a decade.

          Volcano-time is (somewhat literally) glacial; I’d kill for a fast forward button.

          • There is always Hawaii, in case Iceland is too slow 🙂

            Although there is no longer any subglacial activity there so a tradeoff I guess. But the red eruptions are much more spectacular IMO, especially the really powerful ones. Big grey clouds envoke a deep sense of primal fear, if Hunga Tonga Hunga Ha’apai is a typical ignimbrite then there is no volcano watching, there is nowhere close enough that is safe, and the eruption is already over by the time you know what has happened…

            Being completely realistic, Laki wouldnt kill anyone today. Not that it would be pleasant but given how people in Hawaii literally lived within a few km of a SO2 source that was not all that much less intense (fissure 8) and didnt even comment on it…

          • Volcanoes can still surprise us. That’s maybe the best scientific law about volcanoes. Therefore it’s still like a football bet to bet on the icelandic volcano which erupts next. We understand the causal relations and correlations, but not the “what’s next” question. So Katla can remain silent for long time or surprise us tomorrow. Science tells that the most likely eruptions on Katla are 0.1km³ explosive eruptions. That’s around VEI4.

            Speculation about what volcanoes will do next and which will do something exciting are a way to feed the human passion for volcanoes.

          • Chad it’s in big part thanks to your incredible knowledge of Hawaii and willingness to share your thoughts that I have the respect for and interest in Hawaiian volcanism that I do. You make it difficult not to be intrigued by.

            I just have a very intense fascination with plinian volcanism. I discovered this website by searching for articles, general info, and ultimately papers on the Vesuvius 79CE eruption around the time of the Soufriere eruption. My parents actually retired in and live in the Lesser Antilles so I began consuming everything I could find about that eruption and ultimately developed an intense, unceasing fascination with explosive volcanism that lead me to this site. I remembered seeing Vesuvius in person when I studied in Italy in 2008, and the accounts / descriptions of the eruption were equally captivating and horrifying.

            Since then my fascination has only grown. I always appreciate and always hunger to learn more of all types of volcanism. This discipline has fully supplanted meteorology which I almost went to school for and have had a lifelong (since I was five or six) intense passion for, along with all things space related.

            TLDR: I’m addicted to big grey clouds that go boom, but thank you for making me realize how interesting the red liquid stuff is too.

          • I have, among my papers, a copy of Haraldur Sigurdsson’s et al,[Cashdollar and Sparks] paper on the reconstruction of the 79 A.D. eruption of Vesuvius which he was kind enough to send to me and sign, among others which accompanied same, including one which appeared in a 1985 issue of National Geographic Research. . A veritable storehouse of information on the event which, once read, answers many questions. I pray what you have mentioned having referenced in your own quest has included these.

      • Drumplots at Katla (aus) are suggesting rock fracturing is the primary mechanism of the earthquake swarm. The swarms in recent weeks/days/hours are clearly episodic… indicating a steady/increasing rate of pressure must be building at depth. As of now, there have been 8 M3+ earthquakes, many/most of which occurred within a period of only a few hours, and almost all ~ 0.1km in depth (though some are as deep as ~4km). Methinks that given Katla’s history of uber-fast run-ups to an eruption, earthquakes of this size and frequency at such shallow depth would have culminated in either an eruption (by now) or a continuation/increase in the quake swarm if magma was on the move?
        Geothermal/steam-driven activity typically shows up as episodes of tremor…often immediately following an earthquake that opens some new pathways for fluids to migrate through…and the aus drumplot shows a sorta-similar signature concurrent with this recent swarm. But, the pseudo-tremor could also just be micro-aftershocks following the bigger rock-fracturing events, which also could be happening?
        ATTM, IMO (as of June 30) is on the fence whether or not magma is on the move…but increased melt water draining off the mountain along with elevated levels of volcanic-related dissolved gasses would seem indicate magmatic gasses and heat are starting to leach through the surface crust under Mýrdalsjökull…i.e. similar to what happened in 2011 when Katla got restless with a large swarm and an associated jökulhlaup, but nothing happened.
        IMHO, the next 48-72hrs will tell a lot whether it’s just water percolating down+some elastic rebound going on that’s creating the swarm, or whether Katla will finally let loose with it’s long-speculated eruption following the eruption of Eyjafjallajökull in 2010.

        *image deleted as requested by commenter – admin

        • Ummm, apologies for the totally unrelated graphic that just got accidently posted of global seasurface temperatures. The correct graphic should have been a link to the Aus drumplot.

          If a dragon could oblige, please delete the bogus SST graphic? Thank you.

    • IMO reports an increase in electric conductivity in the glacial river Múlakvísl, which indicates an increased percentage of geothermal water in the river. People are warned to go near the outlet, due to potentially elevated levels of dangerous gases. They also warn about increased risk for rock and ice collapse due to the earthquake activity.

      • Does that sound like a subglacial eruption? Or just ice melt and excessive shaking?

        • Just normal geothermal activity. Potentially a jökulhlaup in the making.

        • Or maybe I should say increased geothermal activity rather than just normal activity. There’s no eruption at the moment, that would show tremor on the seismographs. IMO also says there’s no increased chance of an eruption, but they are monitoring the data and following the situation closely.

      • How would a subglacial Geysir look like? Imagine Steam Boat Geysir of Yellowstone below Myrdalsjökullen. How would we notice a subglacial hydrothermal eruption of this?

    • We don’t know much about Katla, but I think some predictions can be made based on the type of volcano it is. Katla is a bimodal caldera system with a shallow magma chamber. Presumably there is an open pipe of magma straight up into the shallow chamber, with continuous but fluctuating input of magma, or sometimes drainback. As it inflates, it will generate earthquakes in fault systems of the caldera structure, a bit like Axial Seamount, or Kilauea. So perhaps these swarms are driven by inflation of the shallow magma chamber, the long-term build-up to an eruption. I have little idea of how much it takes for it to erupt, since we don’t have measurements reaching back to the last event. Presumably it will snap at some point, but that could be fast and with little warning, the short-term precursor (the intrusion towards the surface) could very well take place within several hours or less for a caldera system like Katla.

      • Katla probaly haves a constant supply too but very small indeed, at least what reaches the shallow chamber, althrough well below Grimsvötns supply and nothing compared to Kilauea. Still Katla probaly have a bigger supply than most silent subduction zone volcanoes that spend 1000 s of years doing nothing … most subduction volcanoes is barely ticking as active magmatic systems and explains why they erupt sillic stale mushes

      • Kīlauea has done kinda the same thing, with the exception of the “background noise” when the chamber and, without warning (except for the earthquakes that would occur hours before and eruption), begins a new eruption. I guess it is a thing with a special few of them at different stages, with Hekla being the most notorious of them all.

  25. Around Thursday is a good time to look for the “weekly activity report” of GVP:
    It summarizes what has happened during the week (Wednesday-Tuesday) before and looks for volcanoes which have done something new, changed behaviour or shown unrest. This week it was five volcanoes:
    Ubinas (Peru): Began a strombolian (ashy) eruption after three days of increased seismicity. Ubinas is Peru’s most active volcano with intermediate to Rhyolite magma. Most eruptions are strombolian, but it can occasionally do Plinians.
    Mayon (Philippines): Effusive lava dome and flow. The dome had partial collapses with Pyroclastic flows.
    Lokon-Empung (Sulawesi): Small ash plumes. A volcano that’s often active, but without large hazards.
    Kuchinoerabujima (Japan): Increased number of volcanic earthquakes. Danger for sudden explosions (bombs, pyroclastic flows).
    Klyuchevskoy (Kamtchatka): New Strombolian activity. It is the volcano where the Hawaiian-emporer chain is subducted below Kamtchatka. It is often active, mostly mild, but can also do big eruptions.
    So far no unsual volcanic things, mainly small eruptions on nearly always active volcanoes.

    • “Klyuchevskoy (Kamtchatka): New Strombolian activity.”

      Won the bet, at least partly. I said earlier this month (June 11, checking back the comment) that Klyuchevskoy would be one of the next volcanoes to erupt, alongside Piton de la Fournaise and Fernandina.

        • Yes and looks larger than the smaller eruptions before clearly is a radial eruption fissure intrusion

          • Not to big, fissure is under 1 km long and the fountains are not that tall. It is close to one of the 2019 and 2020 eruption sites.

            The thing about this location though is that most eruptions that happen here seem to start small and get a lot bigger near the end, not big in overall terms compared to some other places but it is a ramp up of more than an order of magnitude. The eruptions that happen on the east flank of the volcano at the surface are radial to the summit but probably follow the structure of the east-west rift zone that goes across the whole volcano at a perpendicular angle to the more obvious rifts that control spreading. Eruptions outside of the Enclos caldera to the west happen from this rift.

            The fissure is pretty visible ov video here:



          • Given how many eruptions have happened in the past 9 years it is a bit surprising no intrusions have left the caldera. The last eruption to leave the caldera was in 2005 although only the dike exited, the vent erupted on the inner wall and then again inside a valley lower down that went back into the caldera but was probably technically outside of the bounding fault. The last vents to erupt completely outside the caldera were in 1998, but these were very small.

            Historically an eruption has happened outside of the caldera every couple decades. The longest gap was 154 years between 1823 and 1977. The shortest gap was only two years between 1774 and 1776. Recent mapping has shows that there are probably double the number of eruptions outside the Enclos as have been actually reported, there were quite a lot in the later half of the 18th century, and if 2005 is technically counted then there have also been quite a lot in the past 50 years too, I guess the big eruption in 2007 probably slowed things down a bit but then that was 16 years ago now.

        • Only one volcano remaining :), although it is the riskiest one, Fernandina. Fernandina is far more inflated than it was before its last eruption, so it should only be a matter of time, anyway.

        • Yes perhaps the intrusion is moving downslope, it could erupt down at the bottom of the mountain in the next few hours or days.

    • “So far no unusual volcanic things”.

      That’s how it is with volcanoes. You have a bunch of stratovolcanoes slowly effusing lava or puffing a little ash and not much else. Every once in a while you have a fissure eruption in a shield volcano, or a paroxysm of Etna that puts a good show for the webcams. And then comes that rare VEI 6 that is over before you learn about it, but you will keep talking about for the rest of your lifetime.

      • The “usual” volcanic behaviour becomes more interesting in neighbourhood of big cities or other human structure. Popocatepetl with its usual activity matters much for millions of people in Mexico City, while similar active volcanoes far off from civilization on Kamtchatka or Andes get less attention. One example is the volcano Kadovar on a lonely island near Papua New Guinea island. It began 2018 to erupt strombolian eruptions. That was pretty new for the volcano and its island. But there were only few people living, and the volcano has become forgotten for public attention.

  26. There is apparently a large deep intrusion ongoing on Reykjanes, it isnt clear exactly where which might be the fault of google translate but it looked like it meant that all of the active volcanoes might well be getting fed by the same source ultimately. So another eruption is very likely and probably not far away, although maybe not until 2024.

    I guess eventually another volcano in Iceland will break the streak but it goes to show how active Reykjanes is when magma can escape, its a spreading ridge that is clamped shut 3/4 of the time, so it has to make up in the other quarter and we get to see that in action now.

    I do hope there is consideration to move the airport though, it isnt unrealistic to expect an ashy eruption near Eldey, or a longer flow to cut off the main highway.

    • Indeed, there are quakes around Kleifarvatnet. Would mean a shift of activity from Fagradalsfjallet to “mother system” Krysuvik. But the quakes are very shallow for an intrusion. Shouldn’t it begin more deeply and move slowly up?

  27. Seeing a lot of comments about Katla’s “swarm” and while Katla is an exciting volcano (My favorite Icelandic volcano) we need to remember some things. This volcano loves making harmless glacial quakes due to the volcano’s strong geothermal heat and hydrothermal system. We’d want to see constant deep quakes below 0.7 km and we want more consistent and constant earthquake activity. The more shallow the quake at Katla, the less you need to worry about it.
    There has been some deep quakes but not enough for me to get excited. It’s possible that some increased heat or volcanic fluid is entering the shallow chamber but clearly not enough to cause any significant instability. I’d want to see VLF and LP quakes along with consistent inflation before I’d get excited.

    • Katla is showing above normal background activity. So something’s going on, whether or not it leads to an eruption this time. She would do a fissure eruption so you might not get a lot of deep quakes. But even basalt plus glacier can lead to a lot of ash.

      Anything over a 5M, regardless of depth, would get me looking for the tin hat …

      • The series of earthquakes comprise of one M4.4 and 8 aftershocks of M3. All shallow, near the surface. That is well beyond typical summer activity. I would suspect hydrothermal activity, but nothing strong enough to break through the ice. That makes it very hard to know whether it is a minor eruption, phreatic activity or otherwise. Even IMO may need time for this.

  28. Congrats! Pretty courageous of yours. Jesper the sulphurwalker. I must admit that I prefer this comfy kind of travelling (not much sweat, no sulphur, better temperature):

    cable car to Teide, short walk

    • Tenerife is a nice place, it too have beautyful archictecture and scenery and specialy the west side of the Island, its also warmer than Sicily on avarge all year around with cooler summers.

      Teide while not very productive, is still an enormous behemoth of a volcano! many 1000 s of km3 for the whole Island and its been there for a very long time growing very slowly for 20 million years. Lots of volcanic variation too, from blocky domes and blocky flows to fluid lava tubes all magmas are generaly very alkaline there

      • Yeah, moderate climate all year, sun in summer around 14h, in winter like ten h as closer to the equator.
        I guess that one day in the future, possibly in the deep future, the behemoth might become alive and do another caldera-forming collapse unless there is a plume after all which now feeds La Palma and El Hierro further west.

  29. Short ot: Looking forward to “Oppenheimer”, the film, although I would have preferred Adrien Brody, better eyes for the part. The whole bunch in America and Cavendish (also Denmark and some in Germany) with the exception of the spies were interesting, ingenious and often very human, the time was suspense and horror, both. Szilárd said later that he wouldn’t have written the letter to Roosevelt which went to Einstein for signature if he had known that the Germans wouldn’t get far enough. But as nobody knew that, the Manhattan Project was necessary. There was a lot of regret among the physicists about Japan, and some had wanted that the bomb explode high in the air above Tokyo as a warning sign. As a consequence some and not too few took a stance against the H-bomb.
    There were great personalities among them. Isidor Isaac Rabi is interesting, John van Neumann, Fermi of course. I am not a fan of Teller for obvious reasons and also not of Truman the Pres.
    I think it was a smear campaign against “Oppie” when he was subject to hearings and lost his security clearance as he didn’t support the proliferation of atomic weapons and the development of the H-bomb. And Rotblad who defected from the Manhattan-Project and signed the Einstein-Russell-Manifesto has my sympathies.
    So now I am wondering what messages the film will transmit. Start in American and British theatres July 21st.

    • Oppenheimer is likely a figure of history that the contemporary citizen only knows from books. If the Russian Tsar bomb which can be accessed through Youtube and the coming motion picture don’t give substance to Oppenheimer’s concerns, one wonders what will. Nuclear weapons in the hands of the military in the late 40’s and early 50’s {e.g. MacArthur’s conflict with Truman over using them in Korea] was the equivalent of giving a loaded gun to a three-year old as a play toy. Due to advances in the knowledge base of all the sciences impacted by the use of this energy, humankind have since matured, somewhat. As I see it, that has been made clear, not only by Chernobyl disaster, but by the concerns over tactical nuclear weapons being deployed by Russian near the Ukraine.

      • Indeed.
        Thank you.
        Charles Oppenheimer, the grandson:
        “So if humanity will create technology, despite its level of danger, how will we manage it? That is always the question, and it is a question of human relations more than technical science. Our science may have advanced to new heights, but inside, human beings remain, to a significant degree, the tribal apes who grew together for millions of years in natural competition and conflict. There are, of course, some modern and evolving forms of cooperation, and of new consciousness. The question is whether humans can fundamentally change their ways of relating and create forms of international cooperation that are more akin to science-based policy than ancient tribal warfare.

        With the benefit of hindsight, it’s clear the policy suggestions scientists made in mid-1945 through 1947 in regard to dealing with nuclear weapons—placing them under international control, among other things—could have worked and prevented an arms race. It’s not surprising US and other world leaders didn’t choose to work together collaboratively back then. It’s only surprising that choosing to go into a wasteful and dangerous nuclear arms race hasn’t killed us all. Yet.

        Oct. 1962, near Cuba (this was close):

        “The captain of the submarine, Valentin Grigoryevich Savitsky, decided that a war might already have started and wanted to launch a nuclear torpedo. Unlike other Soviet submarines armed with the “Special Weapon”, where only the captain and the political officer were required to authorize a nuclear launch, the authorization of all three officers on board the B-59 were needed instead; this was due to Arkhipov’s position as Commodore of the flotilla. The three men were captain Savitsky, political officer Ivan Semyonovich Maslennikov, and executive officer Arkhipov. An argument broke out between the three of them, with only Arkhipov against the launch.”

        “His persuasion effectively averted a nuclear war which likely would have ensued if the nuclear weapon had been fired”

        Somebody made me aware of this man at some point in the last couple of years. We should learn about him in school, nowadays at least. All that knowledge appeared after the Berlin wall had come down. He knew like Szilárd, Rotblad, Einstein or Oppenheimer and some like them what is at stake: The life of billions of people (and animals of course).

        And I assume that Roosevelt might have decided for a warning blast. Kennedy or Obama wouldn’t have dropped the devices on two cities (assumed). So unfortunately in the end we are very dependant on single people.

  30. Have not see this in a while.
    2023-06-30 22:59:30
    Shows nice on seismometers.



    • All on the south east flank of Mauna Loa, maybe a flank slip or a landslide. There isnt much showing elsewhere.

      But a flank slip of Mauna Loa might shut off the SWRZ of Kilauea, which looks to otherwise be the only immediate option for a flank eruption now. So could in theory keep magma in the summit until the pressure is so high it bursts out into a rift catastrophically…

      • It is a Pahala spasmodic tremor event; it has the characteristic shape, and HVO has located the strongest spasm at 40 km depth offshore Pahala.

        • I cnnsidered a tremor but it wasnt showing up at Kilauea. I wasnt aware the Pahala tremors were so strong, TRAD is near the summit of Mauna Loa and probably almost 70 km away from the tremor source. Whether the sills are correctly interpreted or not it is pretty clear a lot of magma is present in some form

          The inflation is ongoing as fast as ever too, the recent DI did nothing to slow it only to delay things by a day or so.

          • Mauna Loa started inflating faster around June 24, after a sluggish month with a drainback that undid much of the rise, hard to say if it is something transient or if it will continue. With the extreme Kilauea inflation, un-precedented since well before 2018, and the first Pahala tremor in perhaps months, things are getting lively for the time being.

  31. Jesper, thank you for this excellent article and all the photos. The orange sulfur is an excellent indicator of how how Etna really is. Known as cyclohexasulfur or Rhombohedral Sulfur the S6 molecules have that orange tinge. Unfortunately a quick scan of the internet failed to turn up the temperature regime where this allotope formation is preferred in the fumeroles, but the temperature is definitely hot. See for some more examples of orange sulphur production from hot fumeroles from the Welirang Volcano

    • Yes it was spectacular, the whole Io must be like that I guess fumaroles everywhere almost

  32. Jesper. I heard of somebody my children know who went on Etna for a skitour.

    Is that dangerous?
    Or is it a different part, officially designated for skiing and hiking?

  33. Sadley GF was not with me with my summit hike, she had other stuff to do at home.
    But hopefuly another time at Etna or Kilauea

  34. Another Icelandic swarm of around 84 earthquakes on a ridge called Vifilsfell, between Brennisteinsfjöll and Hengill. I think this one is probably tectonic as it sits near the plate boundary.

  35. Wondering what is going on in Iceland. Seems like there are multiple volcanoes, including a couple decent sized ones, that have been quite ‘noisy’.

    • Grimsvotn is still building to it’s eruption, still slow and steady so far. Katla’s recent quake activity is could be representative weak magmatic activity but it’s more likely that most of the quakes are glacial caused by geothermal activity. Some of the deeper quakes at Katla are interesting but there isn’t a lot of them at the moment. 6 restless volcanoes but nothing to suggest an imminent eruption from all 6
      The situation at Mayon isn’t looking good on the other hand, the pyroclastic flows are traveling further now, around 4 km from the summit. The 6 km exclusion zone should be expanded. Peleean eruptions are nothing to trifle with.
      Seismograph at Aniakchak is back up, tornillos if I am not mistaken?

      • They look very similar to long-period earthquake swarms that Kilauea does every once in a while, with some added tremor or background noise. I tend to think of the LPs as gas explosions/jets underground, although I’m not sure how accurate this is.

        • They can be indicative of many things. With Kilauea they seem to happen for no apparent reason, or rather I don’t know the reason, at Mauna Loa they seem linked to the reactivation of the deep volcanic conduit or surges in supply, at Shishaldin and Villarica they have been linked to strombolian activity.

      • Will be interesting to follow the webicorder from now on

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