'Iceland's iconic volcanoes' lecture

On Monday February 2nd, the Geographical Society took a trip to the RGS in Kensington to hear science journalist Alexandra Witze talk about 'Iceland's iconic volanoes'. She focussed on seven of her 'favourite' volcanoes: Laki, Surtsey, Hekla, Heimaey, Bárðarbunga, Eyjafjallajökull, Snæfellsjökull. These are only a fraction of the more than 30 active volcanoes in Iceland. Witze commented that the extensive volcanic activity on the island is due to its location directly above the Mid-Atlantic Ridge as well as a hotspot. Both of these provide Iceland's volcanoes with molten material.

One eruption well remembered by much of the audience was Eyjafjallajökull, which led to airspaces above Europe closing for 6 days due to the risk of ash entering engines and forming a glassy substance. Despite the publicity given to this eruption due to its international impacts, the effects on Iceland were small compared to some of the others Witze mentioned. For example, Laki erupted in 1753-4 for 8 months, releasing many toxic gases including sulphur dioxide, which directly and indirectly killed many Icelandic people. The lava flows also entered river channels, evaporating the water in them and disrupting hydrological cycles. In total, one fifth of the island's population was killed as a result of this eruption. 

A similar issue with sulphur dioxide is arising with the currently erupting Bárðarbunga volcano. Sulphur dioxide levels in towns near the volcano are well above recommended levels of exposure, and the Icelandic authorities are unsure on how to deal with this. 

The eruption on the island of Heimaey had an interesting story. Lava flows were threatening to cut off an importing shipping route near the harbour on the island, so hundreds of the island's residents attempted to limit the path of the lava by spraying it with water in the hope of it cooling and thus solidifying (and it worked!). 

Alexandra Witze also touched on the historical and cultural importance of volcanoes in Iceland. For example, Icelandic folklore sees Hekla as a gateway to hell.

Although some of the group wanted to hear more about the physical processes behind the volcanic eruptions, I am sure that this talk will prove useful when lower sixth geographers take a trip to Iceland this summer. 

Ella Witts