A piece on why and how volcanic ash can affect airspace.
The Eyjafjallajokull means an island mountain glacier. It is one of the smaller ice caps of Iceland, north of Skogar and west of Myrdalsjokull. The ice cap covers the caldera of a volcano with a summit elevation of 1,651 mts. This volcano has erupted relatively frequently since its last glacial period, most recently in 2010. When it erupted it affected the airspace above it making the movement of some flights difficult which had to leave the path on which they were moving. So the question that many ask is how one eruption in Iceland affect airspace? And what is volcanic ash? And how it can affect our airspace? Let’s take a look at the volcanics behind the problem. When a volcano, charged with gases such as sulfur dioxide and carbon dioxide erupts it can result in large amounts of ash being generated. Add to this, an eruption under ice and you have the added explosivity to pump the ash high into the atmosphere. Ash is made up of very fine particles of volcanic glass formed by the breaking up of bubbles during the eruption. As the magma gets close to the surface, the gases expand forming a volcanic froth, which then fragments into thousands of particles of ash. In the case of the eruption in Iceland, we have added water coming into the system from the ice which flashes to steam under the heat and causes more explosions. If the volcano is powerful enough, as with Eyjafjallajokull, it can eject this ash high into the sky into high atmospheric winds, which can then blow the ash around the globe. These high winds are where our planes fly, so when volcanic eruption results in ash clouds we have to be careful not to fly through them. In the past, when planes have accidentally flown through an ash cloud, the engines have been clogged up with ash causing engine failure. The jet engine can have temperatures up to 2000degree C, which will melt the ash back to lava and stick to the engine parts. In extreme egs, planes have had to literally glide their way out of the ash cloud before engines can be restarted. So when you think of volcanoes as wonderful eg of earth, heat, and power with lava flows, fountains, and explosions, don’t forget they can influence our lives, even if we live a long way away. This whole episode puts volcanoes in a new perspective. Our modern-day lives are more reliant on air travel than ever before, and this is likely to increase. At any stage, there can be many volcanoes erupting around the world. We are likely to see further egs of volcanic ash clouds entering the airspace and new measures will need to be put into place to provide solutions from the lessons learned from Europe’s volcanic ash crisis. Further engine tests may be required, new routing and even an engineering solution to make jet engines less susceptible to volcanic ash. Whatever direction the new plane will take, this volcano has left a lasting legacy in our memories. The skies have never been quieter over London and for some, it provided a chance to look back at lifestyle and wonder what the future holds. As the volcano continues to erupt, new fears are mounting about one of the larger volcanoes nearby, Katla. This volcano is around ten times larger than Eyjafjallajokull and can spew more material. It has erupted with a periodicity of a hundred or so years, the last time it did so very powerfully was in 1918. The volcanic system is a complicated one. Like the plumbing in a bathroom, it can be interconnected underground by a series of pipes and fractures. In some cases when one volcano erupts, it ‘stirs’ others nearby. Will this eruption,’ stir’ Katla into action. That is the big question. For now, we watch and monitor with series of seismic stations to record underground tremors, tiltmeters, and GPS to see if the ground around the volcano deforms and look for the precursors to a new volcanic eruption. One thing is for sure, Katla will erupt again—-Dougal Jerram, volcanologist.