Monitoring glacier-volcano interactions using permanent time-lapse cameras
In a nutshell
Field site: Höfðabrekkujökull, Iceland.
1. Document the sequence of events during the eruption of Katla volcano, including the scale distribution and magnitude of glacial floodwaters, the pattern and depth of ash fallout, and the evolution of the glacial and pro-glacial geomorphology.
2. Determine the velocity of Höfðabrekkujökull using stereoscopic time-lapse feature tracking from two pairs of cameras, and examine the small-scale influences on glacier movement.
3. Examine the change in debris cover on Höfðabrekkujökull over time using stereoscopic measurements of the glacier surface area.
The main aim of this project is to provide the first ever time-lapse capture of glacier-volcano interactions during a volcanic eruption in Iceland. This will be achieved by installing time-lapse cameras in front of Höfðabrekkujökull, an outlet of the Mýrdalsjökull ice cap which is underlain by the Katla volcano. By doing this, we will acquire a unique and detailed view of how a glacio-volcanic system evolves during the course of an eruption. Because of the hazards involved, it has previously been difficult to document these processes and to monitor glaciers safely during an eruption. By observing the glacier with permanent camera platforms, we will eliminate these risks, and gain detailed insight from the onset of an eruption.
Fire and Ice
Iceland is a Nordic island located between the North Atlantic and Arctic Ocean, with the northern tip of the country skimming the Arctic Circle (66°N). Approximately 11% of Iceland is covered by ice, consisting of extensive ice caps and outlet glaciers spread across the island. One of the unique aspects of Icelandic glaciers is that they have an additional influence from volcanic and geothermal sources, with volcanic systems underlying some of the largest ice caps (e.g. Grímsvötn volcano underneath Vatnajökull, Katla volcano underneath Mýrdalsjökull, and volcanoes beneath Hofsjökull and Eyjafjallajökull). Volcanoes which underlie glaciers are known as subglacial volcanoes.
The island of Iceland is a product of a spreading plate boundary called the Mid-Atlantic Ridge, which supplies lava to the surface and forms basaltic rock once cooled. The Mid-Atlantic Ridge is why there is so much concentrated volcanic activity in Iceland.
When volcanoes erupt beneath glaciers, they generate very specific hazards which are a long-term threat in Iceland. They frequently cause extensive flooding, they can enhance the explosive dynamics of volcanic systems, and the deposited ash has disrupted air traffic in the past. The thickness of the ice overlying a volcano is suspected to control its activity, with thicker ice stifling activity as the overlying pressure is greater. In a warming climate, it is predicted that we will see more frequent eruptions in Iceland as glaciers thin and the overlying pressure on volcanoes lessens.
The effect of volcanism on glaciers is very important research in Iceland with the increasing prominence of eruptions in the media, such as the eruption of Eyjafjallajökull in 2010 and Bárðarbunga in 2014-2015. There have been very few direct observations of how glacial systems respond during volcanic eruptions. It is inherently difficult to observe how these systems behave. Satellite imagery is too intermittent to be consistently useful, and the scope for aerial photography is limited by the hazard. Moreover, people are infrequently present during the onset of an eruption, so good observations are often sporadic and fortuitous.
Katla volcano is widely recognised to be overdue for an eruption. Katla is a network of fissures and volcanic features that underlies the Mýrdalsjökull ice cap in the south of Iceland. In the past, it has erupted on approximately a centennial timescale and frequently follows activity in neighbouring volcanic systems. Its last eruption in 1918 was a large explosive eruption judging by the wide range that its ash was scattered to. Katla’s next eruption is predicted to be larger than the eruption of its neighbour, Eyjafjallajökull, in 2010. Therefore it would be a very prominent eruption to study, and with current geothermal unrest in the area, it is likely that this eruption will happen soon. Höfðabrekkujökull was the main outlet of glacial flood water in the previous eruption of Katla (and others in the past). It seems highly probable that this will also be a flood water route during the next Katla eruption, and thus we propose to monitor the eruption from there using permanently fixed time-lapse cameras.
The aim of this project is to provide the first ever time-lapse capture of glacier-volcano interactions during a volcanic eruption in Iceland. By doing this, we will acquire a unique and detailed view of how a glacio-volcanic system evolves during the course of an eruption. Because of the hazards involved, it has previously been difficult to document these processes and to monitor glaciers safely during an eruption. By observing the glacier with permanent camera platforms, we will eliminate these risks, and gain detailed insight from the onset of an eruption.
What’s been done so far?
In September 2015, two time-lapse cameras were installed on Hafursey, a rocky outcrop in front of Höfðabrekkujökull. These cameras have been set in stereo to look at the glacier front, and have been programmed to take photos every 6 minutes. The systems have been designed to be permanent fixtures in the landscape, and will be checked and maintained annually. They are based on the time-lapse cameras we have in place at Kronebreen glacier in Svalbard, which we know are reliable, good-quality systems.
It is hoped that data from these cameras can be used in conjunction with aerial UAV surveys to provide useful material for undergraduate/postgraduate projects. Potential project areas include proglacial geomorphology change and glacier debris cover change. Ofcourse, we will have a close eye on Katla and keep our fingers crossed that the cameras will capture something interesting!
James and Robson (2014) ISPRS J. Photogram. Rem. Sens. 97
– Stereoscopic time-lapse used to examine lava flows at Kilauea, Hawaii and Mount Etna, Sicily
Geothermal unrest at Katla documented by the Icelandic Met Office
– Evidence of geothermal unrest at Kalta from observations of a small outburst flood at Sólheimajökull, one of the ice cap’s outlet glaciers
– John Stevenson’s blog, which contains loads of information about volcanic activity in Iceland including information about ash clouds, and the eruptions of Katla, Eyjafjallajökull and Bárðarbunga