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Imaggeo on Mondays: Polar backbone (Arctic Ocean)

Imaggeo on Mondays: Polar backbone (Arctic Ocean)

This image was taken during the Arctic Ocean 2016(AO16) expedition that ventured to the central regions of the Arctic Ocean, including the North Pole. It shows a pressure ridge, or ice ridge, as viewed from onboard the deck of the icebreaker Oden. It was quite striking that the ice ridge resembled an image of a spine – sea ice being a defining characteristic of the broader Arctic environment and backbone to global climate interactions.

An ice ridge is a wall of broken ice that forms when floating ice is deformed by a build up of pressure between adjacent ice floes. Sea ice can drift quite quickly, and is driven by wind and ocean currents. Ridges are typically thicker than the surrounding level sea ice, being built up by ice blocks of different sizes. The submerged portion of the ridge is referred to as the “keel”, and the part above the water surface is called the “sail”. Ridges can be categorized as “first year” or “multi-year” features, with weathering affecting the morphology.

In the Arctic, such ridges have been measured to in excess of 20 m in thickness including keel and sail. As someone who studies plate tectonics, these collisional boundaries between plates of ice reminded me of a downscaled mountain-building setting.

The AO16 expedition ran from August to September 2016 and involved the Swedish icebreaker Oden and the Canadian icebreaker the Louis S. St-Laurent. A wealth of geological, oceanographic, meteorological data was collected. This period appeared to have coincided with the second lowest extent of sea ice coverage on record (tied with 2007), with around 4.14 million square kilometers.

The geological evolution of the Arctic Ocean in the regions closest to the margins of northern Greenland and the Canadian Arctic Islands are some of the most poorly understood. This is largely a function of the oceanic gyre system, which causes the thickest sea ice to build up in these areas making physical access difficult. From a maritime engineering perspective, the ice ridges pose a challenge and risk to icebreaking operations and navigation. Ice ridges may determine the design load for marine and coastal structures such as platforms, ships, pipelines and bridges, and are important for both ice volume estimations and for the strength of pack ice.

By Grace Shephard, geophysicist from the Centre for Earth Evolution and Dynamics (CEED) at the University of Oslo, Norway.

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/.

Photo Contest finalists 2017 – who will you vote for?

The selection committee received over 300 photos for this year’s EGU Photo Contest, covering fields across the geosciences. The fantastic finalist photos are below and they are being exhibited in Hall X2 (basement, Brown Level) of the Austria Center Vienna – see for yourself!

Do you have a favourite? Vote for it! There is a voting terminal (also in Hall X2), just next to the exhibit. The results will be announced on Friday 28 April during the lunch break (at 12:15).

Last chance to enter the EGU Photo Contest 2017!

Last chance to enter the EGU Photo Contest 2017!

If you are pre-registered for the 2017 General Assembly (Vienna, 23 -28 April), you can take part in our annual photo competition! Winners receive a free registration to next year’s General Assembly! But hurry, there are only a few days left to enter!

Every year we hold a photo competition and exhibit in association with our open access image repository, Imaggeo and our annual General Assembly. There is also a moving image competition, which features a short clip of continuous geoscience footage. Pre-registered conference participants can take part by submitting up to three original photos and/or one moving image on any broad theme related to the Earth, planetary and space sciences.

How to enter

You will need to register on Imaggeo to upload your image, which will also be included in the database. When you’ve uploaded it, you’ll have the option to edit the image details – here you can enter it into the EGU Photo Contest – just check the checkbox! The deadline for submissions is 1 March.

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