In 1900, Iceland was a very different country. It wasn’t a country, for one thing. Although Iceland had been granted self-rule, it was still a part of Denmark and the local leaders were largely Danish-educated. There was still a Danish governor. The position (not the governor) was terminated in 1904. On Dec 1, 1918 the nation officially became independent, and the union with Denmark ended in 1944. In 1900, the country was depopulated: the climate had worsened, and many people had emigrated to Canada. Reykjavik was little more than a small fishing village, and fewer than 80,000 people lived in all of Iceland. (Nowadays there are some 350,000 Icelanders.) It always was a hard place to live. After the settlement era, around the year 1000, perhaps 30,000 people lived in Iceland. The numbers grew and declined with the climate. Even as late as 1700 there were only some 50,000 Icelanders. Laki reduced the population by 25%, in part by mortality and in part by emigration. This nation of fishermen (and women) always lived at the edge of its carrying capacity. Once sailing boats took over from rowing boats, more people could live from fishing and the population could increase, but in Iceland that was a remarkably late change.
And always there were volcanoes and there were eruptions. Demographics and politics has little influence on them. With so few people to watch, minor eruptions in isolated areas (central Iceland and Vatnajokul, especially) may have erupted in vain, and were missed. What was there to see?
There was a lot to see, and few to see it. Iceland is full of volcanoes, and many are considered active. Some (mainly Grimsvotn) erupt every decade, some (e.g. Torfajokull) only once every millennium. But many volcanoes are in regions where no one lives. That makes sense: frequent tephra falls, lava flows and glacial floods do not go well with keeping sheep. The land has changed; areas that were fertile 1000 years ago are now forbidding wastelands. This has to do with the changing glaciers, and the jokulhaups that changed in tandem. Perhaps a future post. The desolation near active volcanoes means that at the start of this post, the beginning of the last century, eruptions were often poorly observed – or perhaps missed entirely. An unusual flood in a river might be the only sign. In the 1920’s some seismographs appeared, and some of what had been hidden became visible. From 1934 Vatnajokull was frequently visited by explorers, and shortly afterwards overflights began. Interestingly, that dramatic improvement in monitoring coincided with a lull in volcanic activity!
But let’s go through the century (and more) of volcanic activity, from the hesitant beginning to the open-science era of VC.
The volcanic century started with activity at Vatnajokul, setting a pattern that was to continue for the next 120 years. This was at a time that scientific exploration of the area was only just taking off. A Danish expedition attempted to map the entire glacier in the period 1902-1904, but they somehow missed all the excitement, and the eruptions of that time are known from distant reports, not from Danish feet on the ground. There were two eruptions during their time, and both seem strangely unusual. Over time eruptions became better observed and exceptions became rarer although not absent. There were fires (fissures), explosions, and in some cases both. Many eruptions were repeat events, others were unique. Some lasted less than an hour, others a decade. And every eruption was a surprise. Let’s look.
In December, fire was seen towards Vatnajkull, by people in northern Iceland. Simultaneously, a jökulhlaup occurred in two rivers: the Jökulsá á Fjöllum and Skjálfandafljót. They were strong enough to damage ferries. This requires that the eruption was from a rift on the north side of Bardarbunga, as these rivers are only fed together from there. A little ash was found later in the wool of sheep from southern Iceland, but it is not known whether that is related. This is one of only two confirmed/likely eruptions of Bardarbunga during the entire 20th century.
Six months later an eruption occurred on the Grimsvotn system, during a jökulhlaup. We don’t know for certain where the eruption occurred. The eruption was described by Pastor Magnús Bjarnason, dated 11 June 1903:
[…]it was nonetheless one of the largest and most frightful of jökulhlaups as it occurred at the same time as an eruption in Skeiðarárjökull which often happens, to a greater or lesser extent, when there is an outburst in Skeiðará river. Flames arose north and west of the so-called Grænafjall mountain, which lies to the north of Eystrafjall, on Thursday 28 May, upon which the floodwaters increased as the glacier melted, searching for channels with such power that they burst open the front of the outlet glacier and surged forwards with blocks of ice that, according to the post bearer, were 60 feet high, and over a wide area there were others on top of them another 25– 35 feet thick.
The Eystrafjall is a small peak on the eastern edge of the Djupa area, due south of Lake Graenelon (a glacial lake that now no longer exists due to the melt of the glacier that dammed it). The eruption is often attributed to Thordarhyrna, a volcano that has not erupted since. But was it? Bjarnason writes that it was in Skeiðarárjökull, and Thordarhyrna is just to the west of that glacier. If we go due north of Eystrafjall, we find Haabunga and Grimsvotn, at the top of Skeiðarárjökull. Thordarhyrna is well to the west.
If we consider that jökulhlaups in the Skeiðará river come from Grimsvotn, that Grimsvotn is due north of Eystrafjall, that Grimsvotn indeed often erupts during a jökulhlaup, and that Bjarnason describes it as a normal eruption (‘often’), it seems unlikely that the eruption came from Thordarhyrna. This appears to have been a normal Grimsvotn eruption, rather than a rare event.
The eruption started explosively, with tephra fall northeast. A ship 30 km off the coast report ash fall. The eruption continued for 5 months, until October. That is unusual for Grimsvotn: its eruptions typically last for a week. Together with Bjarnason reporting ‘north and west’, this may suggest that after the summit explosion, a small rift opened up towards the southwest and that this continued the eruption. But the precise location is unclear, and it is unlikely that the rift extended as far as Thordarhyrna.
A contemporaneous document states that the 1902 and 1903 eruptions came from different mountains, Bardarbunga and Grimsvotn, although it has the order the other way around, something that is incompatible with the location of the jökulhlaups.
As an aside, the first reported name for Vatnajokull is Grímsvatnajökull (The Glacier of Grimur’s Lakes). It derived its name from Grímsvötn (The Lakes of Grimur). However, the name Grimsvotn was also used for Lake Graenelon, and it is not clear which of the lakes was the original name bearer.
1910 Bardarbunga / Hamarinn
After this long diversion, we get to the next contentious eruption. On June 18, ashfalls were reported in southern Iceland. Further ashfalls happened on 15 August and 21 September, and during the last two weeks of October. A flood came down the Skafta river. The location of this eruption is uncertain. A painting with an eruption column aligns it with the East Skafta Cauldron on the Loki ridge, east of Hamarinn. This is a geothermal area; it is not known to be eruptive, but appears to have erupted once since. The long duration suggests a fissure eruption; the most likely origin is Bardarbunga. The eruption was largely below the glacier, but broke the ice a few times.
This eruption started on 25 April 1913. Initially a 5 km long fissure opened at Mundafell, 5 km east of Hekla. This was after several hours of earthquake activity which was felt as far as Reykjavik. This fissure lasted a day. A second fissure, also 5 km long, opened up at Lambafit, 15 km further northeast along the same direction as the previous fissure. This fissure was weaker but lasted much longer, until 18 May. The eruption was effusive and basaltic. Although it was near Hekla, this fissure is not part of the Hekla system. The first fissure produced a lava field of 3.8 km2, while the second fissure covered 6.3km2. The total erupted lava volume is estimated at 0.02 km3. An eruption had happened in 1878 on the same rift but in between the two fissures.
Now it was time for a serious eruption. As if to celebrate Iceland’s full independence which began on Dec 1, Katla broke the ice. The eruption started on October 12; it lasted for 3 weeks. The eruption started in the southeastern side of the caldera, made short shrift of the 400-m thick icecap, went airborne, and deposited ash widely across Iceland. Even Akureyri on the north coast received an ash layer thick enough for footprints.The strongest explosions came early in the eruption, but minor explosions continued for weeks. Lahars came down the river valleys: the estimated 8 km3 of flood water carried house-sized glacier blocks with it. Of the 0.8 km3 of tephra, half was washed down with the flood and half was explosively ejected. (Some estimates of the volume are higher.) Even the ice of Vatnajokul was blackened by the ash, and was difficult to cross for a year after: sledges and skis do not cope with tephra. The south coast was reshaped by the flood sediment which extended the coast line by 2 km. This was a high VEI-4 eruption as is typical for major events in Iceland, VEI-5 being fairly rare here.
Katla would not erupt again in the 20th century, apart from very minor hydrothermal events which stayed well below the ice.
The minor rift activity in Vatnajokull now moved north, to Askja. A large eruption in 1875 had left a crater lake, called Öskjuvatn. Over the next 40 years it slowly grew as the crater continued to collapse. Now the area came back to life. Solfatara activity had been noted a few years before and this may have been a precursor of the first eruption in March 1921.
Four small lava flows formed in 1921, 1922, and 1923. They are called Bátshraun, Mývetningahraun, Kvíslahraun, Suðurbotnahrau; all flowed into the lake. In 1926, a lava flow formed a small island in the southern part of the lake; the island is now called Askjur. A much larger lava flow (0.22 km3 DRE) came from a 6-km long fissure on the southern side of the lake. The lava flow, called Thorvaldshraun (not the only lava flow in Iceland with this name!), it formed between 1924 and 1929, perhaps in multiple episodes. The lava flowed eastward from the rift, and is on average 5 meter thick. The earlier eruption were on the ring fault, but the NNE-SSW orientation of the new fissure instead followed the line of the rift zone along which Askja lies. The earlier flows had resolved the stress left from the crater formation, and now the large scale stress regime of the northern rift had taken over.
After almost two decades, Grimsvotn was ready to try again. This was a violent eruption which distributed a thin layer of ash across northern and eastern Iceland. The ash fell for three days, from 5 to 7 Oct; the large majority of it was on Oct 6. The eruption happened at the end of a jökulhlaup. This is a fairly common event: the emptying of the lake can trigger an eruption that was already building. The jökulhlaup produced some 7 km3 of water. Whereas the previous Grimsvotn eruption (1903) was a relatively rare rift, this was a more typical summit eruption, brief, explosive, but with little or no lava involved.
1927 Esjufjöll (uncertain)
This eruption was not observed, but was inferred: In the beginning of September 1927, a jökulhlaup came down the Jökulsá á Breiðamerkursandi, towards the east coast, brining a smell of sulfur. This is the only jökulhlaup known from this river. It is however insufficient to define as a definite eruption, as solfataric sulfur can also accumulate in a glacial lake. The event is notable because one person died from the flood. If this was an eruption, this would be one of only two volcano casualties during the century.
Very little is published on this event. It is reported to be north of Grimsvotn, perhaps Gjalp. No earthquakes were reported.
This was the first well-studied eruption in Vatnajokull. It started, as often for Grimsvotn, with a jokulhaup. The Skeidará river began to slowly rise on March 22. The full jokulhaup came a week later, and peaked on March 31. The flow reached levels of 40,000 m3 per second, carrying ice blocks as big as houses and covering the entire flood plain. The flood abated on the next day. In the mean time, the eruption began on in the evening of March 30. On the next day the eruption cloud reached 13 km in height, and ashes spread east and northeast. The eruption quickly subsided, and fully ended in the middle of April. Subsequent expeditions found scoria and pumice around the eruption site, and two new craters in the southwestern part of the caldera. The easternmost crater was 500 m in size. The ice below the rim of the caldera had sunk by 200 meters since two Swedish students had rediscovered the caldera in 1919. In addition to the tephra, the eruption produces hyaloclastites below the ice, with a volume of 0.03 km3.
This started out as a repeat event of 1934. In April, a jokulhaup of similar size to that of 1934 covered the entire floodplain, stretching 50 km wide. The eruption that followed remained subglacial and was not noted above the ice cap. The reason for this was found later: the eruption had taken place not underneath the fragile ice around the lake, but 10 km north, near Gjalp. Here, a 2km wide cauldron had formed, 150 meters deep in the centre. A rift-like depression in the ice pointed directly at Grimsvotn. The ice rift was 1 km wide and more than 100 meter deep. The ridge below has a volume of 0.4 km3, and this is assumed to be the total volume of the eruption. That puts it among the larger eruptions in Iceland of the 20th century. The eruption likely had started earlier, around the middle of March. Melt water which forms in the region around Gjalp flows into the caldera lake and this can trigger a jokulhaup. Caldera eruptions such as 1934, in contrast, tend to come after a jokulhaup.
After this eruption, Grimsvotn did not have another certified eruption for almost 50 years. In fact all of Vatnajokull went quiet.
The union with Denmark ended on 17 June 1944, and now Iceland stood on its own (leaving the minor issue of the British occupation aside). The first eruption of the nation was a memorable one. Hekla had been quiet for some time (the repose time was 101 years). Now it came back with a vengeance, with its largest eruption in the 20th century.
The eruption began on 29 March. As usual with Hekla, it started highly explosive. The initial explosion lasted an hour, and reached a height of 30 km. Intermittent explosions continued for several months. Effusive lava flows followed. In total 0.74 km3 of lava was erupted; the flows covered 40 km2, on either side of the summit rift. The eruption lasted for 13 months, well into 1948. But the eruption did not end when it ended. CO2 continued to seep from the ground for several months, and collected on the west side of the mountain where both birds and sheep were killed. These were the first recorded volcanic casualties in Iceland during the 20th century, other than the possible 1927 eruption.
The eruption began on Oct 12 with intense solfatara activity, before progressing to a significant effusive eruption on Oct 26. It occurred on a fissure north of the caldera, and the lava flowed east.
The eruption ended in the first half of December (the precise date is not known. The tholeiite lava had a volume of 0.1 km3; the flow extended some 11 km. Early lava was a’a; later it became pahoehoe. Thorarinsson wrote an impression of the early phase of the eruption, obtained during an overflight: “The glowing river that belched forth through Oskjuop was a spectacle beyond description. The eruption column rose to 6000 m and its upper parts were lit by the full moon and flaming northern lights. A strong wind blew from the north and carried the column southwards. Now and then four fountains of brightly glowing lava were visible through the clouds; the easternmost was highest and its height was estimated at 500 m.”
1963 – 1967 Surtsey
Now 15 years of volcanic silence followed, apart from one suspected hydrothermal event under the icecap of Katla, in 1955. The silence broke in an unexpected place: 140 meters under the sea, off the southern coast. The activity started in mid November, and within a day broke the surface. The island of Surtsey began to form. The eruption continued intermittently until June 1967, along a 6-km which covers 14 km2. Two further islands formed during the eruption, but unlike Surtsey they survived only for weeks. The eruption produced about 0.7 km3 DRE. When the eruption ended, Surtsey contained two 140 m high tuff cones and a small pahoehoe lava field. The island was immediately proclaimed a nature reserve.
On May 5, at 20:58 an earthquake swarm hit Hekla. That was as much warning as it was going to give: the explosion occurred 25 minutes later. It lasted several hours; the eruption column reached 16 km height. This was quite a damaging eruption, not so much because the explosion itself, but because of the amount of fluorine which was deposited over the grazing ground to the northwest. Several fissures opened and closed, as is usual with Hekla; the last fissure closed on July 5. The lava covered an area of 18 km2. The volume is reported as 0.21 km3
Icelandic eruptions tend to be fairly safe. This is because they tend to be fairly predictable, not in terms of when they will erupt, but where. There are some 45 volcanoes-at-risk, and in addition the ‘dead zone’ and the northern volcanic zone can produce long-distance rifts. Icelandic people are by-and-large sensible, and no one lives there. But sometimes even Icelanders can be surprised. Heimaey was the biggest surprise of the century. It erupted suddenly, unexpectedly, at night, and almost in the middle of a town. The successful evacuation was greatly aided by luck. A 1-km shift, or just different weather could have caused disaster with perhaps significant casualties. The eruption lasted from 23 Jan to 28 June. It build a new cone (Eldfell), buried part of a town, and activated a 3.5 km rift (10 km if a small submarine event is added). There were two casualties: one horse, and one person who died indoors from the poisonous gasses.
1975 -1984 Krafla
After this excitement came a prototypical Icelandic rift eruption. The Krafla volcano is a low 25-km wide shield, with an oversized 9-km caldera. On Dec 20 it announced its presence with an earthquake followed by a small eruption within the caldera. The eruption was quickly quenched when a dike formed and diverted the magma supply. The dike stalled before it could reach the surface. Three weeks later, a M6.5 earthquake occurred near the Grimsey rift, perhaps aided by the filling of the rift. Now the stage was set. Over the next decade, 20 such events happened, each with magma intruding into the central chamber, followed by the formation of a dike either north or south, extending some 10 km. Initially, lava was rare. There were two small fissure flows in 1977, whilst the next flows did not appear until 1980. Each flow lasted no more than a day. But from mid-1980 the flows grew in size, became longer and lasted up to a week. There were two further eruptions in 1981 and one in 1984. Afterwards there was some activity around Grimsey for another 5 years, but no further eruptions. The longest eruption of the era had come to an end.
The event was almost a carbon copy of the 1725-1729 eruption. The two lava fields are closely overlapping. The 1975-1984 eruption eventually covered and area of 36 km2, 1 km2 more than the flows 250 years earlier. The eruption produced about 0.35 km3 of lava. This is very little, compared to the duration of the activity. This is in part because of a low magma supply in this region, and in part because much of the intrusion went into filling the rift. A similar effect had been seen in the 1875 Askja eruption, where the eventual volume of the crater far exceeds at of the erupted lava. Much of Iceland’s growth occurs underground.
The 1970 eruption had given 25 minutes warning. But in 1980, Aug 17, there was only 23 minutes between the onset of earthquakes at 13:04 and the onset of the eruption at 13:27. The eruption lasted only 3 days, unusually short for Hekla, but it had the usual mixture of an explosive start lasting several hours, and an effusive follow-on. The eruption cloud peaked at 15 km. The volume of the eruption was 0.12 km3.
On April 8 Hekla resumed its previous eruption, albeit very restrained. The eruption was not observed (the main event was between 2 and 5 am), but the earthquake activity was noted and there was some tephra fall. The eruption cloud did not reach much above 5 km. Small lava flows came from the summit rift, amounting to 0.05 km3. Everything ended on April 16. This was such an unusual event (for Hekla) that it is often considered as a late activity of the 1980 eruption.
After almost 50 years of withdrawal, Vatnajokull came back in action. But it did so somewhat hesitantly. A small fissure eruption started on May 28, with along the southern crater wall of Grimsvotn. It was preceded by 6 months of enhanced earthquake activity: Hekla can learn from this! The eruption lasted only a few days. It produced hyaloclastites with a volume of around 0.01 km3.
The 1983 event was repeated a year later. After a few months of earthquake activity, a brief eruption occurred in August. It lasted less than an hour and was unobserved apart for some tremor, but the depressions left in the ice showed that this was indeed a mini-eruption. One wonders whether the 1983/84 Grimsvotn hick-ups were related to Krafla 1975 and Askja 1961, all small events on or near the rift zone. Much stronger activity on the rift was to come in 2014.
After the embarrassment of 1981, Hekla tried again a decade later. It caught observers by surprise. There was a small earthquake swarm at 16:30, but the eruption itself (17:05) was first noticed by people on a nearby farm. This initial explosive event lasted 2 hours, and gave rise to an eruption plume 12 km high. The effusive phase that followed focussed on a short rift where a cinder cone build up. The lava field extended to 23 km2. The volume of the eruption was around 0.2 km3. The eruption ended on 11 March.
On 30 September Grimsvotn rejoined the world of the true volcanoes. It erupted on its northern rift, at Gjalp. The eruption took more than a day to break through the ice, 600 meter thick. By the time it had managed to do so the strongest eruption as over, and the cloud nowreached only a few km high. The plume came up through a 100 m high ice chimney. Tephra topped at 500 metres. But underneath the ice this was a substantial eruption, which led to the formation of 6 km long and 500 m high subglacial hyaloclastite ridge.
The unusual aspect of this eruption was that it started at Bardarbunga. On Sept 29 it suffered an M5.7 earthquake, followed by a swarm which then migrated to Gjalp. Was this in fact a Bardarbunga eruption? The composition of the ejecta did not indicate this, but neither were they that typical for Grimsvotn. The 4-km long fissure, though, pointed at Grimsvotn and left little doubt about the culprit. A later re-analysis of the data suggested that there may have been a minor eruption in Bardarbunga before the M5.7 earthquake, and that afterwards the earthquake swarm came from a collapse on the crater rim. This reduced the pressure on Gjalp, and allowed the rift there to open.
As is common, the Gjalp eruption caused the Grimsvotn lake to rise, break the ice, and escape as a major jokulhaup. A water volume of 3.5 km3 came down the river. This is much less than early in century. Possibly the thinning of the ice cap in recent decades doesn’t allow the lake to rise as far.
This was Grimsvotn’s 4th rift eruption outside of the caldera in the 20th century. The commonly quoted number is that 6 out of 7 of Grimsvotn’s eruptions take place in the central crater. This was not the case in the 20th century, up to this point. The 1996 eruption produced around 0.4 km3 DRE but little tephra.
On November 6, there apparently was a brief eruption in Bardarbunga. It was picked up by seismographs, and lasted less than half an hour. The eruption formed two ice cauldrons in the most southeasterly part of the Bárðarbunga caldera. The eruption was a day after a jokulhaup from Grimsvotn, but that may be a coincidence.
Now Grimsvotn came back into its stride with its frequent but fairly minor eruptions. The 18 December eruption began after a ew months of earthquakes, and a dike injection underneath the caldera. The eruption lasted ten days. It occurred on a fissure along the southern caldera wall. Less than 0.1 km3 of lava was ejected.
We leave out an uncertain mini eruption at Katla in June 1999, and move back to Hekla. On Feb 26 it gave a longer than usual warning that something was brewing: earthquakes started more than an hour before the eruption. The signal was recognized in time, and an advance warning went out on the radio 20 minutes before the explosion: a unicum for Hekla! The initial explosion reached 11 km height. It gave rise to some pyroclastic clouds, the first reported Icelandic pyroclastics of the century. The eruption lasted until March 5. The lava covered 17 km2, and the eruption volume was around 0.1 km3. This event continued the pattern that after the larger 1947 and 1970 eruptions, the eruptions became less strong and shorter. Hekla has not erupted since.
A jokulhaup occurred on Oct 27, and it immediately led to warnings of an impending eruption, based on previous earthquake activity and the know relation between jokulhaps and Grimsvotn caldera eruptions. The eruption started on Nov 1, on a 1-km fissure along the southeastern caldera wall. It lasted for five days. The eruption quickly broke through 200-meter thick ice, and the column reached 12 km in height. This was a typical small Grimsvotn eruption.
This was one of the more unexpected eruption of this period. Eyjafjallajökull erupts perhaps once every 300 years. There had been signs. The first intrusion was as early as 1994. A further intrusion in 2009 and one in early 2010 brought the pressure to breaking point. It broke on March 20 on the east side of the volcano, at Fimmvörðuháls. The fissure dried up a few weeks later, on April 12. Two days later, at 1:15 on April 14 a weak summit eruption began. At 6:50 the ice cover broke and the real eruption followed. It was not a major event, but luck was lacking. The eruption column was 10 km high and very ashy — and the wind blew in the wrong direction. European air space closed, and the world’s era of volcanic fragility began. The eruption ended after 40 days, on May 22. The world never went back to its old self-confidence. This was the time that (apart from Indonesia which had learned long before), governments first began to listen to volcanologists.
In the evening of May 21 Grimsvotn erupted once more. It was a large eruption, orginating from the same location at the southwestern corner of the lake as the 2004 eruption but much more significant. And unusually, this eruption was not closely associated with a jokulhaup. The eruption plume reached 17 km. Ash fell widely over southern Iceland. The eruption quickly slowed down and it ended by May 28. Some air space was briefly closed, but overall the wind was much more favourable than during 2010, and during the peak of the eruption the ash was blown away from the main transatlantic routes. The eruption was a high VEI 4.
2014 – 2015 Holuhraun
What can I say? The time period we cover ended as it began, with a fissure eruption from Bardarbunga. But there the similarity ends. Holuhraun was the most voluminous eruption of this period, and by far the longest continuous eruption. It started in Aug 2014 and ended in Feb 2015. The magma was transported more than 40 km down-rift before breaking the surface. As the fissure erupted, the caldera collapsed in a seemingly never-ending sequence of earthquakes. The eruption volume is 1.2 km3 and the flows covered an area of 80 km2 in the unoccupied region between Vatnajokul and Askja. The eruption occurred in the same region as the 1797 rift eruption. In Iceland, eruptions repeat.
The next 120 years?
We have left out a number of possible but disputed eruptions. Even so, this is an impressive list. It shows the phases, the rising and waning of eruptions with the quiet era mid-century. It shows the number of rift eruptions. And it shows that not all eruptions are expected or predicted.
What is next? Which volcanoes will announce themselves in the next 120 years? We can make one easy prediction: Grimsvotn is likely to erupt within the next year, and some 10 times more during the period. The 2021 eruption will likely be a small eruption from the summit, as that is the most common. After that, three other regions are on the volcanic radar. Oraefajokull has had a significant intrusion in recent years. It is coming back to life and perhaps in another 10 or 20 years, after another 1 or more intrusions, will give way. If that happens, it may well be the largest Icelandic eruption of the period. The Reykjanes peninsula is showing increased activity, and seems ready to play its part again after 800 years of silence. It is uncomfortably close to towns, although Reykjavik itself is safe. Askja is having earthquake swarms, and seems a likely candidate for the next rift. Otherwise, we may expected 1 or 2 Bardarbunga eruptions and 1 to a few Hekla explosions. And we should expect something unexpected. After all, this is Iceland: independent, self-reliant, and ready to play on the world stage.
And how has Iceland fared? In 1900 it was fishing nation with some agriculture. In 2020, fishing remains important but for the economy, it has been overtaken by tourism. And the tourism uses those volcanoes. In the past, a badly placed eruption wiped out a quarter of the country. Now, volcanoes account for a quarter of its economy. How times have changed.
Albert, November 2020