GeoLog

Imaggeo

Imaggeo on Mondays: Wandering the frozen Svalbard shore

Imaggeo on Mondays: Wandering the frozen Svalbard shore

These ethereal, twisted ice sculptures litter the frozen shoreline of Tempelfjorden, Svalbard, giving the landscape an otherworldly feel and creating a contrast with the towering ice cliff of the glacier and the mountains behind. They are natural flotsam, the scoured remnants of icebergs calved from the Tunabreen glacier, washed up on the shoreline.

These icebergs were calved from the Tunabreen glacier, which flows into Tempelfjorden from its source at the Lomonosovfonna ice cap. Tunabreen is a surge-type glacier, which means that it periodically switches between long periods of slow, stable flow to short-lived periods of very fast flow during which it advances. Tunabreen has historically surged approximately every 35 to 40 years, and its calving front advanced more than 2 kilometres during a surge in 2004.

Tunabreen is one of the glaciers monitored by the Calving Rates and Impact on Sea Level (CRIOS) project, an international initiative that involves several institutions. The glacier tends to slow during the winter months when there is less meltwater available to lubricate the sliding of ice over bedrock. Glaciologists were caught by surprise, therefore, when in late 2016 the glacier was observed to accelerate to speeds in excess of 3 m/day from the more usual 0.4 m/day. This acceleration began at the glacier terminus and spread up to 7km upstream over the following months. Tunabreen appeared to be surging decades earlier than expected!

The causes of this change in the glacier’s behaviour are not certain. However, the onset of this acceleration followed an unusually warm and wet autumn. Sea ice, which usually acts to oppose the flow by applying a resistive pressure against the calving front, also failed to form in Tempelfjorden over the winter. Both of these factors likely contributed. As a result of the flow acceleration, the surface of the glacier has become heavily crevassed, posing a hazard to travellers and glaciologists hoping to cross it!

I was fortunate to be able to visit Tunabreen in March 2017, as part of a glaciology course taught at UNIS, the University Centre in Svalbard. The view of the glacier’s 100ft high calving front framed by the mountains in the background is spectacular, and the trip by snowmobile was a fantastic daytrip. The surge continued throughout 2017 and early 2018, with the calving front advancing by more than a kilometre during that period. Since the summer of 2018, flow velocities have been decreasing, so it appears that the surge may have come to an end. This episode illustrates that there is still much we have to learn about the dynamics of surge-type glaciers, and that they can still take us by surprise!

Matt Trevers, PhD Researcher, Centre for Polar Observation and Modelling, University of Bristol

Further reading

Glaciers On The Move

Tunabreen may be surging decades earlier than expected (The University Centre in Svalbard)

What is going on at Tunabreen? (Penny How)

The recent surge of Tunabreen, Svalbard (Adrian’s glacier gallery) 

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

Imaggeo on Mondays: The ash cloud of Eyjafjallajökull approaches

Imaggeo on Mondays: The ash cloud of Eyjafjallajökull approaches

This photo depicts the famous ash cloud of the Icelandic volcano Eyjafjallajökull, which disrupted air traffic in Europe and over the North Atlantic Ocean for several days in spring 2010. The picture was taken during the initial phase of the eruption south of the town of Kirjubæjarklaustur, at the end of a long field work day. Visibility inside the ash cloud was within only a few metres.

The eruption was preceded by years of seismic unrest and repeated magma intrusions. A first effusive fissure opened outside the ice shield of the volcano at the end of March 2010, followed by an explosive eruption in the main crater of the volcano in April 2010.

Iceland was well prepared for the eruption – the rest of the world obviously was not. The region around Eyjafjallajökull is sparsely populated, residents were prepared days before the eruption and the evacuation went smoothly. However, the grain size of the ejected volcanic ash was fine enough so that the unfavourable and unusual wind direction during these days transported the ash all the way to Europe and led to air space closures almost all over the continent.

By Martin Hensch, Nordic Volcanological Center, University of Iceland (now at Geological Survey of Baden-Württemberg, Germany)

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

Imaggeo on Mondays: Exploring ice in the deep

Imaggeo on Mondays: Exploring ice in the deep

The occurrence of sporadic permafrost in the Alps often needs challenging fieldwork in order to be investigated. Here in the high altitude karstic plateau of Mt. Canin-Kanin (2587 m asl) in the Julian Alps (southeastern European Alps) several permanent ice deposits have been recently investigated highlighting how also in such more resilient environments global warming is acting rapidly. Important portions of the underground cryosphere are actually rapidly melting, loosing valuable paleoarchives contained in the ice.

Description by Renato R. Colucci, as it first appeared on imaggeo.egu.eu.

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

Imaggeo on Mondays: Watching the world from space with EarthKAM

Imaggeo on Mondays: Watching the world from space with EarthKAM

This photo was taken from the International Space Station (ISS), approx. 400 km above the Earth, in the NASA-led educational project Sally Ride EarthKAM (www.earthkam.org), Mission 58, April 2017. The image was requested by a team of 10th and 11th grade students from the National College of Computer Science, Piatra-Neamț, Romania, coordinated by me. The lenses used on the digital camera mounted on the ISS are 50 mm focal length. The area photographed is a region of 185.87 km wide and approx. 123.5 km long, from Utah, USA. The view is spectacular, a perfect equilibrium between mountains, canyons, lakes and bays.

It’s just one of the pictures that my students had the opportunity to get from the ISS. Even though we weren’t there on the ISS to trigger the camera, all the locations in which the photographs were taken were chosen by us, on the track of the ISS.

The project activities were very complex. The students learned about the Earth, its rotation and gravity, and about the space station and its orbit. They completed their knowledge of physics, understanding how from the ISS orbit we can have another perspective of the Earth. They chose the places on the Earth to be photographed, studied these regions and monitored the weather conditions for better photo opportunities. They identified the places on Google Earth, analysed the photos and then created QR codes for some of them.

Below are the QR codes for the photo “Awesome trip above the Earth”:

 

The ISS became an innovative learning environment for the students. The astronauts’ availability for engaging in educational programmes, sharing their extraordinary experiences of becoming aware of the beauty and fragility of the Earth from the ISS orbit, has increased the attractiveness of learning about space. As Sally Ride, the first American astronaut woman on the ISS, said:

“When I was orbiting Earth in the space shuttle, I could float over to a window and gaze down at the delicate white clouds, brilliant orange deserts, and sparkling blue water of the planet below. I could see the coral reefs in the oceans, fertile farmlands in the valleys, and twinkling city lights beneath the clouds. Even from space, it is obvious that Earth is a living planet.”

The photo was integrated into a photo exhibition called “The Earth’s Colors” that I realised with my students at my college, which led the viewer on a global trip, discovering how beautiful and fascinating the Earth viewed from Space is. Satellite photography offered my students a new world perspective, encouraging them to ask questions and to search for the answers. It was a new and exciting way to travel and discover our planet.

The project was a great opportunity, not only for my students but also for thousands of other students around the globe, to study the Earth in a way that complements different subjects in order to better understand our world. It also has strengthened my conviction that, as the teacher and Challenger astronaut Christa McAuliffe said:

“…space is for everybody. It’s not just for a few people in science or math, or for a select group of astronauts. That’s our new frontier out there, and it’s everybody’s business to know about space.”

By Diana Cristina Bejan, physics teacher, The National College of Computer Science, Piatra-Neamț, Romania

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.