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April GeoRoundUp: the best of the Earth sciences from the 2017 General Assembly

April GeoRoundUp: the best of the Earth sciences from the 2017 General Assembly

This month’s GeoRoundUp is a slight deviation from the norm. Instead of drawing inspiration from popular stories on our social media channels and unique or quirky research featured in the news, we’ve rounded up some of the stories which came out of researcher presented at our General Assembly (which took place last week in Vienna). The traditional format for the column will return in May!

Major story

Artists often draw inspiration from the world around them when composing the scene for a major work of art. Retrospectively trying to understanding the meaning behind the imagery can be tricky.

This is poignantly true for Edvard Munch’s iconic ‘The Scream’. The psychedelic clouds depicted in the 18th Century painting have been attributed to Munch’s inner turmoil and a trouble mental state. Others argue that ash particles strewn in the atmosphere following the 1883 Krakatoa volcanic eruption are the reason for the swirly nature of the clouds represented in the painting.

At last week’s General Assembly, a team of Norwegian researchers presented findings which provide a new explanation for the origin of Munch’s colourful sky (original news item from AFP [Agence France-Presse): mother-of-pearl clouds. These clouds “appear irregularly in the winter stratosphere at high northern latitudes, about 20-30 km above the surface of the Earth,” explains Svein Fikke, lead author of the study, in the conference abstract.

“So far observed mostly in the Scandinavian countries, these clouds are formed of microscopic and uniform particles of ice, orientated into thin clouds. When the sun is below the horizon (before sunrise or after sunset), these clouds are illuminated in a surprisingly vibrant way blazing across the sky in swathes of red, green, blue and silver. They have a distinctive wavy structure as the clouds are formed in the lee-waves behind mountains”, writes Hazel Gibson (EGU General Assembly Press Assistant) in a post published on GeoLog following a press conference at the meeting in Vienna (which you can watch here).

With coverage in just over 200 news items, this story was certainly one of the most popular of the meeting. Read more about the study in the full research paper, out now.

What you might have missed

Also (typically) formed in the downside of mountains and in the conference spotlight were föhn winds. The warm and dry winds have been found to be a contributing factor that weakens ice shelves before a collapse.

Ice shelf collapse has been in the news recently on account of fears of a large crack in the Larsen C Ice Shelf generating a huge iceberg.  Though the exact causes for crack generation on ice shelves remain unclear, new research presented by British Antarctic Survey scientists at the conference in Vienna highlighted that föhn winds accelerate melting at the ice shelf surface.  They also supply water which, as it drains into the cracks, deepens and widens them.

Meanwhile, deep under ocean waters, great gouge marks left behind on the seafloor as ancient icebergs dragged along seabed sediments have been collected into an Atlas of Submarine Glacial Landforms, published by the Geological Society of London. The collection of maps sheds light on the past behaviour of ice and can give clues as to how scientists might expect ice sheets to respond to a changing climate.

Drumlins (elongate hills aligned with the ice flow direction) from the Gulf of Bothnia in the Baltic Sea. Credit: Atlas of Submarine Glacial Landforms/BAS

Closer to the Earth’s surface, groundwater also attracted its fair share of attention throughout the meeting. It’s hardly surprising considering groundwater is one of the greatest resources on the planet, globally supplying approximately 40% of the water used for irrigation of crops and providing drinking water for billions around the world. ‘Fossil’ groundwater, which accumulated 12,000 years ago was once thought to be buried too deep below the Earth’s surface to be under threat from modern contaminants, but a new study presented during the General Assembly has discovered otherwise.

Up to 85% of the water stored in the upper 1 km of the Earth’s outermost rocky layer contains fossil groundwater. After sampling some 10,000 wells, researchers found that up to half contained tritium, a signature of much younger waters. Their presence means that present-day pollutants carried in the younger waters can infiltrate fossil groundwater. The study recommends this risk is considered when managing the use of fossil waters in the future.

Links we liked

News from elsewhere

The spectacular end to the Cassini mission has featured regularly in this month’s bulletins.

During its 13 years in orbit, Cassini has shed light on Saturn’s complex ring system, discovered new moons and taken measurements of the planet’s magnetosphere. On September 15th,  the  mission will end when the probe burns up in Saturn’s atmosphere.

On 22 April, the final close flyby of Saturn’s largest moon, Titan, propelled the Cassini spacecraft across the planet’s main rings and into its Grand Finale series of orbits. This marks the start of the final and most audacious phase of the mission as the spacecraft dives between the innermost rings of Saturn and the outer atmosphere of the planet to explore a region never before visited; the first of 22 ring plane crossings took place on 26 April.You can watch a new movie which shows the view as the spacecraft swooped over Saturn during the dive here.

For an overview of highlights from the mission and updates from the ring-grazing orbits that began in November 2016 watch this webstream from a press conference with European Space Agency scientists at the General Assembly last week.

To stay abreast of all the EGU’s events and activities, from highlighting papers published in our open access journals to providing news relating to EGU’s scientific divisions and meetings, including the General Assembly, subscribe to receive our monthly newsletter.

Imaggeo on Mondays: An epic ‘house’ move across the ice

Imaggeo on Mondays: An epic ‘house’ move across the ice

In 2008 the NEEM Deep Ice Core Project was initiated by 14 partner countries in Northwestern Greenland (camp position 77.45°N 51.06°W) with the aim to drill from the very top of the  Greenland ice cap to its base; obtaining  ice from as far back as the last interglacial period- the Eemian – some 130,000 years old.

At the start of the 2008 field season, the NEEM camp consisted of a single heavy-duty tent, some vehicles, and a skiway. Over the summer months, the facilities could host up to 30 researchers at a time. Extra heavy duty tents were built to accommodate everyone comfortably. However to further ease the work of the many researchers who contributed to the project over several years and to create a common space, ‘the dome’ was build. Spread over three stories, the round black building included a kitchen and eating space on the ground floor, a working and relaxing area on the first floor for and a top floor for observing weather conditions before incoming flights.

After three summers of drilling through the icecap, bedrock was reached in 2010 and the Eemian ice was secured.

The 2011 season was spent on surface programs and some drilling into bedrock. Finally, in 2012 the deep ice core drilling project NEEM was terminated and camp was dismantelled.  Most of the heavy equipment was left on the NEEM site with supplies and equipment stored inside the main dome, in two garages, and on seven heavy sleds. The large dome was put on skis with the intention of moving it to the next drilling site, though exactly where was yet to be determined and  funds also needed to be secured.

In 2015, a group of 12 people, including myself, travelled back to the NEEM site. We packed down the the garages and stored them on sledges, we removed 3 years’ worth of accumulated snow (~1.5 m) from the sledges packed in 2012 and from the 45 ton main dome, and finally made the whole lot ready for moving.  Using specialist snowploughs (known as a PistenBully, sponsored by NSF ) we relocated to our new drilling site, EastGRIP at the North East Greenland Ice Stream (NEGIS).

The trip began on Monday 18th May in the afternoon. Progress was slow. By 20.30 the traverse consisting of 8 vehicles had traveled 24 km along the ice flow divide towards the south-east, towing an incredible  143 tonnes worth of equipment, not including the weight of the vehicles themselves.

After an arduous eight day traverse, on 26th May the convoy made the last 53 km of the journey and arrived at EastGRIP in the afternoon. On arrival, the team only had 3000 litres of fuel left, which would have only supported the traverse for one more day. The total route travelled was 449 km.

The focus of the work at the new ice core camp at EastGRIP is different to that of the NEEM project. While the overall aim is to also drill to the bottom of the Greenland ice sheet, this time the goal is to understand the fast flowing ice at NEGIS.

Ice streams, such as NEGIS, are responsible for draining a significant fraction of the ice from the Greenland Ice Sheet. By drilling to the bottom of the ice sheet the project hopes to gain new and fundamental information on ice stream dynamics, thereby improving the understanding of how ice streams will contribute to future sea-level change. The drilled core will also provide a new record of past climatic conditions from the northeastern part of the Greenland Ice Sheet which will be analysed at numerous laboratories worldwide. Similar to NEEM the project has many international partners and is managed by the Centre for Ice and Climate, Denmark with air support carried out by US ski-equipped Hercules aircraft managed through the US Office of Polar Programs, National Science Foundation.

By Helle Astrid Kjær, researcher at the Niels Bohr Institute,  University of Copenhagen

 

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/

Announcing the winners of the EGU Photo Contest 2017!

The selection committee received over 300 photos for this year’s EGU Photo Contest, covering fields across the geosciences. Participants at the 2017 General Assembly have been voting for their favourites throughout the week  of the conference and there are three clear winners. Congratulations to 2017’s fantastic photographers!

Penitentes in the Andes by Christoph Schmidt (distributed by imaggeo.egu.eu). This photo was taken in the Bolivian Andes at an altitude of around 4400 m. The climatic conditions favour the formation of so-called penitents, i.e. long and pointed remains of a formerly comprehensive snow field.

Symbiosis of fire, ice and water by Michael Grund (distributed by imaggeo.egu.eu). This picture was taken at Storforsen, an impressive rapid in the Pite River in northern Sweden.

Movement of the ancient sand by Elizaveta Kovaleva (distributed by imaggeo.egu.eu). In the Zion National Park you can literally touch and see the dynamic of the ancient sand dunes.

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/.

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