For some reason lately I’ve found myself watching a number of documentaries on periods in history when the UK or, very often, the whole of Europe has suffered a year or more of crop failures, disease and famine. Pretty much all of them, it transpires, were the result of a massive volcanic eruption somewhere in the world. I’ve always considered the UK to be pretty safe from natural disasters and is one of the reasons I give for choosing to bug in, however, I’m now thinking that perhaps it is actually directly vulnerable from volcanic eruptions, despite having no volcanos of its own.
The potential volcanic eruption, oft cited by preppers, that is assumed will affect the whole of Europe and the Eastern Seaboard of the US, is the eruption of the Canary Islands volcano, Cumbre Vieja, causing a giant tsunami to radiate outwards to the US and to Europe. Cumbre Vieja is certainly active, and historically blows once or twice every 100 years – the last eruption being 1949. The western side of Cumbre Vieja is known to be unstable and the fear is that in the next eruption the whole side of the volcano will slide into the sea triggering the tsunami. Historical records suggest that the UK has possibly experienced a tsunami from the west before: on 30th January in 1607 there was a flood of the Bristol Channel, on the west coast of the UK, causing the death of an estimated 2,000 people and the destruction of much property and farmland. However, whether or not the flood was actually caused by a tsunami or a storm surge such as the one that flooded the east coast of the UK in 1953 is open to debate given other evidence: such as reports of a storm surge occurring the same night in Norfolk – which is on the other side of the UK and highly unlikely to be the result of a tsunami coming from the Atlantic. Either way DEFRA believes that any flood caused by a tsunami-type event ‘are unlikely to exceed those anticipated for major storm surges. All major centres of development on coasts and estuaries have defences that have been designed to withstand such surge waves’ (See: http://archive.defra.gov.uk/environment/flooding/risk/tsunami.htm). So, whilst East Coast US preppers may fear Cumbre Vieja, I don’t.
The real threat to the UK from volcanos comes not from what they might toss into the sea, triggering a tsunami, but from what they toss into the air. In 2010 Eyjafjallajökull (pronounced : “Ay-yah-fyad-layer-kuh-tel”) erupted in Iceland sending around 1 cubic kilometre of ash over most of Europe, which resulted in the highest level of air travel disruption in Europe since the Second World War. Although there were reports of noticeable ash fallout on cars in the UK, quite frankly I noticed far more crud on my car from the Saharan dust storms early in 2013 than I did from Eyjafjallajökull. (Seriously, you could have filmed “Lawrence of Arabia” on my bonnet! I swear there were dunes!) Financially Eyjafjallajökull was bad for Europe, but it was not a huge European ecological disaster. It did, however, make one aware that volcanos hundreds or even thousands of miles away elsewhere in the world can have a direct affect little old Blighty.
The seismic energy of earthquakes is measured by the Richter scale, the Saffir-Simpson scale estimates a hurricane’s potential and the Fujita scale rates a hurricane’s intensity. Volcanic eruptions are measured using the Volcanic Explositivy Index (VEI). It primarily measures the volume of pyroclastic material ejected by the volcano (volcanic ash, tephra, pyroclastic flows etc.) and also takes into consideration the height of the eruption column and the duration of the eruption. Eruptions rated at VEI 1 produce between 0.0001 and 0.001 cubic kilometers of ejecta. Above VEI 1, the scale becomes logarithmic, meaning that each step in the scale represents ten-fold increase in the amount of material ejected. So the highest VEI of 8, ejecting at least 1,000 Km3 of ejecta, is 1,000 times more powerful than a VEI of 4, which in turn is 1,000 more powerful than a VEI 1. It is believed that the Yellowstone eruption some 640,000 years ago, Lake Toba, 74,000 years ago, and Lake Taupo 26,500 years ago all would have measured 8 on the VEI scale. One of the largest 8s being the Wah Wah Springs eruption some 30 million years ago (but now dormant in Utah!) which produced an estimated 3,200 km3 of erupta. To date on the earth there have been 47 VEI 8 eruptions, all identified via geological study as none has occurred in recorded history. To compare with recorded eruptions, the infamous Krakatoa eruption in 1883 had a VEI of 6 (and also triggered several tsunami). Novarupta in 1912 also had a VEI of 6. Mount Vesuvius’s eruption in AD 79, smothering Pompeii and Herculaneum with scorching ash is rated as VEI 5 the same as the recent barely-documented Pinatubo eruption in 1991 (reducing sunlight by 5% and causing global temperatures to fall by 0.4C) and the well-documented Mount St Helens eruption in May 1980 (though some sources cite St Helens was “only” a VEI 4). Eyjafjallajökull in 2010 had a VEI of 4.
However, on 10th April, 1815 Mount Tambora on the Indonesian island of Sumbawa erupted. It had a VEI of 7 producing 160 km3 of ejecta and is the largest recorded eruption in history. The volcanic winter that followed, where temperatures world-wide dropped 0.4C to 0.7C caused the following year, 1816, to become known as: The Year Without Summer. The whole of the Northern Hemisphere was affected. In the US the average Last Frost Date for New York State is April 30th – May 10th. In 1816 the ground was still frozen on 9th June. On July 7th it was still so cold that crops struggled to grow. On August 23rd there was another widespread frost. (As a Brit I love the idea that there is usually a specific date after which there will no more frosts! Just doesn’t happen like that in the UK. Snowballs in June have been know!). Further south crops did grow, but the price of food rose dramatically. Throughout Europe cool temperatures and heavy rain caused crops to fail resulting in the worst famine of the 19th Century. Riots, arson and looting took place in many cities. In northern Asia the cold weather killed crops and livestock. The Tambora eruption disrupted the Chinese monsoon season causing massive floods. In India the delayed summer monsoon caused late torrential rains aggravating the spread of cholera from Bengal to Moscow.
But volcanos don’t need to have a massive explosion to cause problems. What they throw out, and how they release it is as important as how far it travels into the sky (explosive and effusive eruptions), and the prevailing weather conditions can determine who dies and who lives. On 8th June, 1783 another Icelandic volcano, Laki (or more correctly Lakagígar “Craters of Laki” pronounced: “La-ka-ghee-yur“) erupted, rating a VEI 6, partly because of the eight month length of its eruption. Amongst other volcanic debris, Lakagígar spewed out an estimated 120,000,000 long tons of sulphur dioxide. Because of the unusual high pressure over Iceland that summer, rather than travelling up to the unpopulated North Pole, the poisonous cloud of sulphur dioxide travelled in a circular, clockwise direction over Scandinavia, through what is now the Czech Republic, down through Germany, west through France before heading back north and blanketing the UK. The cloud hung around for months not dissipating until the Autumn. It was so thick that boats were unable to navigate using the sun and had to stay in port, so fishing and trade were greatly affected. Workers out in the fields suffered enormously: when it comes into contact with the moisture in the lungs, sulphur dioxide turns into sulphuric acid, burning the lung tissue and causing victims to choke. Reports indicate that deaths in Chartres were up 5% in August and September 1783. In the UK deaths in Bedfordshire and Lincolnshire, which are large farming areas, were estimated to be two or three times the normal rate. An estimated 23,000 people died in the UK from poisoning directly related to the sulphur dioxide cloud. In Iceland, the source of all that sulphur, 50% of their livestock died as a result of the poisoning leading to a famine that killed approximately 25% on the population.
The longer term meteorological impact of Lakagígar caused many more deaths than just the immediate poisonings. The weather in the summer was very hot causing massive thunderstorms with giant hailstones. What crops survived the poison and the lack of sun where swamped with flooding from the storms. Famine was widespread in Europe. By contrast the following winter was very severe, not just in Europe but also in North America. In total the Lakagígar eruption is estimated to have killed 33% of the Icelandic population and over six million people world wide: 0.6% of the total world population at the time.
You might not be able to pronounce them, but the Icelandic volcanos may well severely affect your future. If one of the unpronounceables blows with a VEI 5, VEI 6, or heaven forbid, a VEI 7, the UK lies directly in its path. Ironically it’s one of Iceland’s more English language friendly volcanos, Katla (pronounced: “Cat-la“), that is the current contender for possible UK disaster. Situated on the south coast of Iceland just 27km from Eyjafjallajökull and believed to share magma tunnels with it, Katla is very large, historically erupting with a force of VEI 4 to VEI 6, and very active, erupting on average once every 50-95 years with over 20 reported and confirmed eruptions since AD 950. It’s been dormant since its last eruption in 1918, the longest period of dormancy known. Moreover, history tells us that it has always erupted shortly after its little neighbour Eyjafjallajökull has blow its top. Katla certainly grumbled a lot in 2011, the year after Eyjafjallajökull brought Europe’s aviation to its knees, some people going as far as to say it did actually have a minor eruption, but the consensus is that Katla is now overdue for an explosion and is monitored closely. It’s current status is “restless”.
How would the UK cope with months of a sulphur dioxide cloud hanging over us, meaning you couldn’t go outside without wearing a mask? How would our livestock cope with the sulphur poisoning? How would Europe cope with a year’s worth of crop failure on all outdoors crops? Would even the massive Spanish polytunnels manage to produce food without enough sun? How would Europe and the US cope with a volcanic winter? What would be the world-wide financial implications of such a situation? If you consider that the painter Turner personally witnessed and painted the effects in England of three massive eruptions: Tambora (VEI 7) in 1815, Babuyan Claro (VEI 4) in the Philippines in 1831, and Cosiguina (VEI 6) in Nicaragua in 1835, the likelihood of there being at least one massive eruption somewhere which will affect the whole of Europe in your lifetime is quite high.
Makes ya think….!
The UK Government now ranks an eruption from one of Iceland’s volcanos is as one of the three highest natural hazards the UK faces, with a 0.5% to 5% chance of such an eruption happening in the next 5 years. See: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/211867/NationalRiskRegister2013_amended.pdf