Iceland review - 2015, Qupperneq 68

Iceland review - 2015, Qupperneq 68
66 ICELAND REVIEW 66 ICELAND REVIEW A VOLCANO’S WHIMS Starting on August 31, 2014, and carry- ing on until February 27, 2015, the erup- tion originated in one of Iceland’s largest volcanoes, Bárðarbunga, which lies under Vatnajökull glacier. It was preceded by a series of violent earthquakes. “At first, while the earthquakes were taking place under the glacier, we were concerned about flooding and ash fall,” reveals Sigurður, explaining: “We tend to look at the last scenarios we’ve experienced: Eyjafjallajökull in 2010 and Grímsvötn in 2011.” Both sub-glacial eruptions led to extensive ash fall—which, in the case of Eyjafjallajökull, grounded international air traffic for days—and a glacial outburst flood from Eyjafjallajökull destroyed farmland. Given the size of Bárðarbunga and the volume and location of the glacial rivers potentially affected by a sub-glacial erup- tion, the worst-case scenario was devastating. “This was the main point of discussion with the Civil Protection Department, which informed inhabitants of the areas likely affected, drawing up evacuation plans,” rec- ollects Sigurður. “We were racing to place samplers in glacial rivers, looking for signs, predicting where the flooding would be the worst. When the earthquakes extended away from the northern edge of the glacier we were incredibly relieved, thinking: ‘this will be another tourist eruption.’” In March 2010, one month before Eyjafjallajökull burst, a minor eruption occurred in the same volcanic system on Fimmvörðuháls, a ridge between two gla- ciers. The spectacular lava fountains and falls attracted a multitude of tourists on foot, snowmobile and helicopter. In the case of Holuhraun, the pattern of the earth- quakes indicated that an intrusive dike was channeling magma away from the massive Bárðarbunga caldera in Vatnajökull and towards an ice-free no-man’s land in the remote northeastern highlands, which— were it to reach the surface—would neither cause an explosive, ash-producing eruption, nor glacial outburst floods. “But then we started worrying they would attack Askja!” Sigurður says of the next big concern. But as the earthquakes were approaching the infamous volcano—the mother of some gigantic past eruptions— they stopped in the old lava field Holuhraun where the dike reached the surface, spewing lava from a 1.5-km (1-mile) long fissure, shooting fire fountains as high up as 100 meters (328 feet) in the air. Impressive as they were, it soon became clear that this was no ‘tourist eruption’ and the scientists weren’t about to get a break, as Sigurður describes: “When we realized the extent of the gas pollution, a new race started, putting up gas, dust and precipitation mon- itoring stations around the country and the Icelandic Met Office developed gas distri- bution forecasts.” BAD OMEN OF A BLUE HAZE In early September a bluish haze was report- ed in East Iceland, the result of volcanic gas released by the eruption. “When SO2 gas interacts with hydrogen, oxygen and sun- light in the atmosphere, sulfuric acid par- ticles are created and a blue haze, blámóða, appears, after which Móðuharðindin was named,” Sigurður says in reference to the consequence of the 1783-84 Skaftáreldar (Laki eruption), when toxic fumes scorched grass and killed livestock, leading to the death of 20 percent of the Icelandic population. The blue haze reached the stratosphere, cooling the climate, causing failed harvests across Europe. “It may even have contributed to the French Revolution,” adds Sigurður. “This made us very concerned. The gas pollution was extreme, peaking at 21,000 µg/m3 in Höfn,” he recollects of the condition in the Southeast Iceland town in late October 2014. People were advised to stay indoors on several occasions in different locations around Iceland. At the eruption site, SO2 levels reached 130,000 µg/m3, and the maximum hourly safety limit of 350 µg/m3 was repeat- edly exceeded across Iceland. “In some places in Europe too, Ireland and Austria,” Sigurður points out. Other gases released by the erup- tion were insignificant in comparison. “The big news was the SO2 pollution,” he stresses. Þórólfur Guðnason, senior epidemiologist at the Directorate of Health, stated in January 2015 that cases of people falling ill after being exposed to volcanic gases at the eruption site had been referred to the directorate. He also mentioned that judging by the sale of asthma medicine and diagnosis at healthcare centers around the country, people had suf- fered increased symptoms from the respira- tory organs since the eruption started. Most such cases were reported in East Iceland. Concerns of acid rain and snow followed. When SO2 dissolves in water it forms sul- furic acid. “We started taking samples from the precipitation and found low pH values in many different locations around the country. The lowest value was pH 3.2 at Borgir near Höfn, which is extremely acid. The most ENVIRONMENT “The thing with dust is that it acts like base, a vaccine. When it reacts with sulfuric acid, it neutralizes it.”
Qupperneq 1
Qupperneq 2
Qupperneq 3
Qupperneq 4
Qupperneq 5
Qupperneq 6
Qupperneq 7
Qupperneq 8
Qupperneq 9
Qupperneq 10
Qupperneq 11
Qupperneq 12
Qupperneq 13
Qupperneq 14
Qupperneq 15
Qupperneq 16
Qupperneq 17
Qupperneq 18
Qupperneq 19
Qupperneq 20
Qupperneq 21
Qupperneq 22
Qupperneq 23
Qupperneq 24
Qupperneq 25
Qupperneq 26
Qupperneq 27
Qupperneq 28
Qupperneq 29
Qupperneq 30
Qupperneq 31
Qupperneq 32
Qupperneq 33
Qupperneq 34
Qupperneq 35
Qupperneq 36
Qupperneq 37
Qupperneq 38
Qupperneq 39
Qupperneq 40
Qupperneq 41
Qupperneq 42
Qupperneq 43
Qupperneq 44
Qupperneq 45
Qupperneq 46
Qupperneq 47
Qupperneq 48
Qupperneq 49
Qupperneq 50
Qupperneq 51
Qupperneq 52
Qupperneq 53
Qupperneq 54
Qupperneq 55
Qupperneq 56
Qupperneq 57
Qupperneq 58
Qupperneq 59
Qupperneq 60
Qupperneq 61
Qupperneq 62
Qupperneq 63
Qupperneq 64
Qupperneq 65
Qupperneq 66
Qupperneq 67
Qupperneq 68
Qupperneq 69
Qupperneq 70
Qupperneq 71
Qupperneq 72
Qupperneq 73
Qupperneq 74
Qupperneq 75
Qupperneq 76
Qupperneq 77
Qupperneq 78
Qupperneq 79
Qupperneq 80
Qupperneq 81
Qupperneq 82
Qupperneq 83
Qupperneq 84
Qupperneq 85
Qupperneq 86
Qupperneq 87
Qupperneq 88
Qupperneq 89
Qupperneq 90
Qupperneq 91
Qupperneq 92
Qupperneq 93
Qupperneq 94
Qupperneq 95
Qupperneq 96
Qupperneq 97
Qupperneq 98
Qupperneq 99
Qupperneq 100
Qupperneq 101
Qupperneq 102
Qupperneq 103
Qupperneq 104
Qupperneq 105
Qupperneq 106
Qupperneq 107
Qupperneq 108
Qupperneq 109
Qupperneq 110
Qupperneq 111
Qupperneq 112
Qupperneq 113
Qupperneq 114
Qupperneq 115
Qupperneq 116
Qupperneq 117
Qupperneq 118
Qupperneq 119
Qupperneq 120
Qupperneq 121
Qupperneq 122
Qupperneq 123
Qupperneq 124
Qupperneq 125
Qupperneq 126
Qupperneq 127
Qupperneq 128
Qupperneq 129
Qupperneq 130
Qupperneq 131
Qupperneq 132

x

Iceland review

Direct Links

Hvis du vil linke til denne avis/magasin, skal du bruge disse links:

Link til denne avis/magasin: Iceland review
https://timarit.is/publication/1842

Link til dette eksemplar:

Link til denne side:

Link til denne artikel:

Venligst ikke link direkte til billeder eller PDfs på Timarit.is, da sådanne webadresser kan ændres uden advarsel. Brug venligst de angivne webadresser for at linke til sitet.