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Imaggeo on Mondays: The retreating glaciers of the Svaneti Range, Georgia

Imaggeo on Mondays: The retreating glaciers of the Svaneti Range, Georgia

Today’s Imaggeo on Mondays picture shows the central section of the Svaneti Range, located in the Svaneti Region – a historic province of northwestern Georgia. The range is the second biggest range formed by the modern glaciation on the southern slopes of the Georgian Caucasus Mountains. In today’s post, Levan Tielidze, a researcher at Ivane Javakhishvili Tbilisi State University, writes about the ice capped peaks of these high mountains and highlights the precarious balance of this cryospheric system.

Svaneti range is approximately 100 km long and is distinguished by the height of its relief, as well as by the fact that the area covered by glaciers in the region exceeds that covered elsewhere in the southern slopes of the Georgian Caucasus.These features define the range and lead it to be divided into three sections: eastern, central (shown in this picture) and western. The eastern and western sections are lower in altitude than the central region and modern ice cover cannot be found there, with the exception of Mount Dadiashi which stands at 3535 m asl.

However, glaciers do cap the peaks in the central areas of the range, and can be found between the sections of Lasili and Leshnuri. Here is where you’ll find the highest peak of the mountain range: Laila (Laila-Lehli) -4009 m asl.

The glaciers in this region are retreating and losing volume. Data from the 1960s indicated that glaciers in the range numbered up to 48 and covered an area of approximately 27.76 km2 , equivalent to the size of just over 2500 football pitches. By 2014 the area covered by the glaciers in the region had shrunk by 27.5% and now only covers approximately 20.13 km2.

Some of the largest glaciers of the northern slopes of the range are formed on Laila peak, which itself is covered by a glacier cap. Among these glaciers the largest is Eastern Laila, located in the Khumpreri River basin. The glacier is formed of two ice streams which flow from separate valleys. In 1960 the glacier area was  close to 5.96 km2; its terminus ended at a height of 2300 meters asl. By 2014 the eastern Laila’s area decreased to 3.55 km2 and has retreated to an altitude of 2640 m asl. The total glacier length is now approximately 4.52 kilometers.

The glaciers are an important source of water for agricultural production in Georgia, and runoff in large glacially-fed rivers (Kodori, Enguri, Rioni, Tskhenistskali, Nenskra) supplies several hydroelectric power stations. In addition, glacier outburst floods and related debris flows are a significant hazard in Georgia and in the Caucasus. Future trends in glacier change are thus a topic of considerable interest to the region.

By Levan Tielidze, Institute of Geography, Tbilisi State University, Georgia

If you pre-register for the 2016 General Assembly (Vienna, 17 – 22 April), you can take part in our annual photo competition! From 1 February up until 1 March, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at http://imaggeo.egu.eu/photo-contest/information/.

Imaggeo on Mondays: Man-made landscape

Imaggeo on Mondays: Man-made landscape

The landscape of the Mersey Estuary in Liverpool Bay is ever changing; it offers the opportunity to observe the changing geomorphology of a river estuary which is closely linked to a very urban and man-made landscape. For more on this unique setting, read today’s Imaggeo on Mondays post brought to you by Maria Burguet Marimon.

This picture was taken at Crosby beach, which is located just at the beginning of the Mersey Estuary in the Liverpool Bay. The current Crosby beach dates back in the beginning to the 20th century, in which the stabilization process of the sand was carried out.

It is important to remark that, during the first half of the 20th century, the estuary underwent a significant period of morphological change. Changes to the ebb and flood tide hydrodynamics in Liverpool Bay, caused by the construction of training walls in the outer estuary, resulted in large-scale movement of sediment into the inner estuary, increasing intertidal area and reducing the estuary volume from 745 Mm3 to 680 Mm3 (Thomas, 2000; Thomas et al., 2002). Since this time, a new equilibrium appears to have been reached and the rate of sediment movement into the estuary has slowed (Halcrow, 2010).

In 2007, following a meeting with the local government, Sefton Council,  sculptures made by Sir Antony Gormley were placed along a stretch of Crosby beach in an art exhibition known as Another Place. A total of 100 cast-iron sculptures were placed facing towards the sea. The idea of the exhibition is to show the statues at different stages: rising from the sand near the promenade to standing at the water’s edge and finally submerging into the sea. It is as if the statues are leaving us willingly but with a tinge of sadness or suffering. Each sculpture faces towards Burbo Bank Offshore Wind Farm, looking for a brighter and more ecological future.

By Dr. Maria Burguet Marimon, researcher at the University of Valencia.

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: night cap over Mt. Fuji

Imaggeo on Mondays: night cap over Mt. Fuji

The first Imaggeo on Monday’s post of 2016 is quite spectacular! It features a lenticular cloud capping the heights of Mount Fuji, in Japan. Erricos Pavlis writes this post and describes how the unusual cloud formation comes about and why Mt. Fuji is such a prime place to catch a glimpse of this meteorological phenomena.

Mount Fuji at more than 3700 m is one of the highest volcanoes in the world and the highest mountain in Japan,located some one hundred or so kilometers southwest of Tokyo.

In November 2013 the International Laser Ranging Service (ILRS) held its annual Int. Laser Ranging Workshop at Fujiyoshida, a resort town very close to the volcano. The venue had a clear shot at the volcano and rewarded us daily with spectacular views of the entire volcano. On the first morning of my stay, November 9, I looked out the window very early on and Mt. Fuji was toped with a lenticular cloud, just like a nightcap for a cold winter night.

Being such a tall mountain and the only one in the area, Mt. Fuji is a perfect candidate to observe this rare kind of clouds that form in the troposphere and mostly over very tall topographic features. The lenticular clouds (formally called Altocumulus lenticularis) are the result of the obstructed wind flow due to an barrier, a mountain for example, but it could also happen with man-made obstacles like very tall buildings. They are formed at right angles to the wind direction and they are categorized in several different types, however, they all have the shape of lens and this has sometimes led viewers believe they saw an Unidentified Flying Object (UFO)! On rare occasions, the lucky ones might see several of these stacked on top of each other with thin layers of air separating them like a pile of pancakes! Even the single one was for me a very pleasant surprise though!

By Erricos Pavlis, Joint Center for Earth Systems Technology, Univ. of Maryland, Baltimore County, Baltimore, Maryland, United States of America.

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/.

The best of Imaggeo in 2015: in pictures

The best of Imaggeo in 2015: in pictures

Last year we prepared a round-up blog post of our favourite Imaggeo pictures, including header images from across our social media channels and Immageo on Mondays blog posts of 2014. This year, we want YOU to pick the best Imaggeo pictures of 2015, so we compiled an album on our Facebook page, which you can still see here, and asked you to cast your votes and pick your top images of 2015.

From the causes of colourful hydrovolcanism, to the stunning sedimentary layers of the Grand Canyon, through to the icy worlds of Svaalbard and southern Argentina, images from Imaggeo, the EGU’s open access geosciences image repository, have given us some stunning views of the geoscience of Planet Earth and beyond. In this post, we highlight the best images of 2015 as voted by our Facebook followers.

Of course, these are only a few of the very special images we highlighted in 2015, but take a look at our image repository, Imaggeo, for many other spectacular geo-themed pictures, including the winning images of the 2015 Photo Contest. The competition will be running again this year, so if you’ve got a flare for photography or have managed to capture a unique field work moment, consider uploading your images to Imaggeo and entering the 2016 Photo Contest.

Different degrees of oxidation during hydrovolcanism, followed by varying erosion rates on Lanzarote produce brilliant colour contrasts in the partially eroded cinder cone at El Golfo. Algae in the lagoon add their own colour contrast, whilst volcanic bedding and different degrees of welding in the cliff create interesting patterns.

 Grand Canyon . Credit: Credit: Paulina Cwik (distributed via imaggeo.egu.eu)

Grand Canyon . Credit: Credit: Paulina Cwik (distributed via imaggeo.egu.eu)

The Grand Canyon is 446 km long, up to 29 km wide and attains a depth of over a mile 1,800 meters. Nearly two billion years of Earth’s geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted. This image was submitted to imaggeo as part of the 2015 photo competition and theme of the EGU 2015 General Assembly, A Voyage Through Scales.

Water reflection in Svalbard. Credit: Fabien Darrouzet (distributed via imaggeo.egu.eu)

Water reflection in Svalbard. Credit: Fabien Darrouzet (distributed via imaggeo.egu.eu)

Svalbard is dominated by glaciers (60% of all the surface), which are important indicators of global warming and can reveal possible answers as to what the climate was like up to several hundred thousand years ago. The glaciers are studied and analysed by scientists in order to better observe and understand the consequences of the global warming on Earth.

Waved rocks of Antelope slot canyon - Page, Arizona by Frederik Tack (distributed via imaggeo.egu.eu).

Waved rocks of Antelope slot canyon – Page, Arizona by Frederik Tack (distributed via imaggeo.egu.eu).

Antelope slot canyon is located on Navajo land east of Page, Arizona. The Navajo name for Upper Antelope Canyon is Tsé bighánílíní, which means “the place where water runs through rocks.”
Antelope Canyon was formed by erosion of Navajo Sandstone, primarily due to flash flooding and secondarily due to other sub-aerial processes. Rainwater runs into the extensive basin above the slot canyon sections, picking up speed and sand as it rushes into the narrow passageways. Over time the passageways eroded away, making the corridors deeper and smoothing hard edges in such a way as to form characteristic ‘flowing’ shapes in the rock.

 Just passing Just passing. Credit: Camille Clerc (distributed via imaggeo.egu.eu)

Just passing. Credit: Camille Clerc (distributed via imaggeo.egu.eu)

An archeological site near Illulissat, Western Greenland On the back ground 10 000 years old frozen water floats aside precambrian gneisses.

Sarez lake, born from an earthquake. Credit: Alexander Osadchiev (distributed via imaggeo.egu.eu)

Sarez lake, born from an earthquake. Credit: Alexander Osadchiev (distributed via imaggeo.egu.eu)

Beautiful Sarez lake was born in 1911 in Pamir Mountains. A landslide dam blocked the river valley after an earthquake and a blue-water lake appeared at more than 3000 m over sea level. However this beauty is dangerous: local seismicity can destroy the unstable dam and the following flood will be catastrophic for thousands Tajik, Afghan, and Uzbek people living near Mugrab, Panj and Amu Darya rivers below the lake.

Badlands national park, South Dakota, USA. Credit: Iain Willis (distributed via imaggeo.egu.eu)

Badlands national park, South Dakota, USA. Credit: Iain Willis (distributed via imaggeo.egu.eu)

Layer upon layer of sand, clay and silt, cemented together over time to form the sedimentary units of the Badlands National Park in South Dakota, USA. The sediments, delivered by rivers and streams that criss-crossed the landscape, accumulated over a period of millions of years, ranging from the late Cretaceous Period (67 to 75 million years ago) throughout to the Oligocene Epoch (26 to 34 million years ago). Interbedded greyish volcanic ash layers, sandstones deposited in ancient river channels, red fossil soils (palaeosols), and black muds deposited in shallow prehistoric seas are testament to an ever changing landscape.

Late Holocene Fever. Credit: Christian Massari (distributed via imaggeo.egu.eu)

Late Holocene Fever. Credit: Christian Massari (distributed via imaggeo.egu.eu)

Mountain glaciers are known for their high sensitivity to climate change. The ablation process depends directly on the energy balance at the surface where the processes of accumulation and ablation manifest the strict connection between glaciers and climate. In a recent interview in the Gaurdian, Bernard Francou, a famous French glaciologist, has explained that the glacier depletion in the Andes region has increased dramatically in the second half of the 20th century, especially after 1976 and in recent decades the glacier recession moved at a rate unprecedented for at least the last three centuries with a loss estimated between 35% and 50% of their area and volume. The picture shows a huge fall of an ice block of the Perito Moreno glacier, one of the most studied glaciers for its apparent insensitivity to the recent global warming.

 Nærøyfjord: The world’s most narrow fjord . Credit: Sarah Connors (distributed via imaggeo.egu.eu)

Nærøyfjord: The world’s most narrow fjord . Credit: Sarah Connors (distributed via imaggeo.egu.eu)

Feast your eyes on this Scandinavia scenic shot by Sarah Connors, the EGU Policy Fellow. While visiting Norway, Sarah, took a trip along the world famous fjords and was able to snap the epic beauty of this glacier shaped landscape. To find out more about how she captured the shot and the forces of nature which formed this region, be sure to delve into this Imaggeo on Mondays post.

The August 2015 header images was this stunning image by Kurt Stuewe, which shows the complex geology of the Helvetic Nappes of Switzerland. You can learn more about the tectonic history of The Alps by reading this blog post on the EGU Blogs.

 (A)Rising Stone. Credit: Marcus Herrmann (distributed via imaggeo.egu.eu)

(A)Rising Stone. Credit: Marcus Herrmann (distributed via imaggeo.egu.eu)

The September 2015 header images completes your picks of the best images of 2015. (A)Rising Stone by Marcus Herrmann,  pictures a chain of rocks that are part of the Schrammsteine—a long, rugged group of rocks in the Elbe Sandstone Mountains located in Saxon Switzerland, Germany.

If you pre-register for the 2016 General Assembly (Vienna, 17 – 22 April), you can take part in our annual photo competition! From 1 February up until 1 March, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at http://imaggeo.egu.eu/photo-contest/information/.

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