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Imaggeo on Mondays: Exploring the underground cryosphere

Imaggeo on Mondays: Exploring the underground cryosphere

The winter season is a good time to take advantage of cold weather activities, whether that’s hitting the ski slopes or warming up by a fire, but for Renato R. Colucci, it’s also one of the best time’s to study the Earth’s underground cryosphere.

Colucci, who took this featured photograph, is a researcher at Italian Institute for Marine Sciences (ISMAR) of the National Research Council (CNR) and is a scientific lead partner for the Cave’s Cryosphere and Climate project, C3 for short. The C3 project aims to monitor, study, date, and model alpine ice cave environments.

This photo was taken by Colucci while he and the C3 project team were surveying a large ice deposit in the Vasto cave, situated within the Southeastern Alps of Italy. Speleologists of the E. Boegan Cave Commission began documenting the caves in this region in the 1960s, making it a great site for studying underground cryosphere today. For the past few years the C3 team has been monitoring the microclimates of these caves as well as analysing how the ice masses within are melting and accumulating ice.

There are many different kinds of ice deposits in caves, but the main difference is how these types accumulate their frozen mass. For some cave ice deposits, like the one featured in this photo, the snowfall that reaches the cave interior amasses over time into solid layers of ice, as is typical for many glaciers. However, other deposits take form when water from melting snow or rain percolates through rock’s voids and fractures, then freezes and accumulates into permanent ice bodies in caves.

These high-altitude underground sources of ice are a lesser-known faction of the cryosphere since they are not very common or reachable to scientists, but still an important one. Often the permanent ice deposits in caves contain pivotal information on how Earth’s climate has evolved over time during the Holocene.

However, if the Earth’s global temperatures keep increasing, this data might not be available in the future. While ice masses in caves are more resilient to climate change compared to their aboveground counterparts, many of these deposits, and the vital data they store, are melting away at an accelerating rate. “Global warming is rapidly destroying such important archives,” said Colucci.

Through this project, the researchers involved hope to better understand the palaeoclimate information stored in these deposits and how the ice will respond to future climate change.

By Olivia Trani, EGU Communications Officer

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: Air samples from afar

Imaggeo on Mondays: Air samples from afar

I’ve taken many photos on fieldwork, everywhere from Malaysia to Antarctica but this particular photo was taken in my ‘home’ lab at the University of East Anglia (UEA) in Norwich, UK. Atmospheric scientists collect air samples canisters such as these from around the world: from high altitude research aircraft (such as the Geophysica), long-term measurement time series (such as Cape Grim) or field campaigns in urban and rural environments.

At UEA we measure these whole air samples for a suite of up to 50 trace gases, covering all the major ozone depleting substances and non-CO2/CH4 greenhouse gases. We measure compounds at ‘parts per trillion’ (ppt) level or below in samples as small as 20 ml. It’s very hard to visualise 1 ppt… but it’s equivalent to about one second in 32,000 years measured in a sample that could fit in an egg cup.

Often these air samples are also analysed at other labs in Europe and other parts of the world, adding to the total number of compounds and isotopes we can quantify. Samples such as these have helped us identify new threats to ozone recovery and to quantify emissions of climatically-important trace gases such as HFCs and PFCs. To measure such trace, trace gases requires an instrument that is both large and temperamental. As such, it doesn’t (well can’t) leave the lab and we bring all the samples back to it. Stopping to imagine where the samples came from and how rare and special they can be (air from 30 km high or from deep in an ancient ice core!) helps me get through the long and labour intensive days in the laboratory.

By Emma Elvidge, University of East Anglia, UK

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 changing landscape of Patagonia

Imaggeo on Mondays: The changing landscape of Patagonia

Pictured here is a snapshot of an environment in transition. Today’s featured photo was taken at the foot of Monte Fitz Roy, a jagged Patagonia mountain located in Los Glaciares National Park on the border between Argentina and Chile.

The Patagonia region in South America is the second biggest source of glaciers in the southern hemisphere, behind Antarctica, but the region is losing ice at a rapid rate.

Satellite imagery analysis over the last few years has suggested that the Patagonia region is losing ice more than any other part of South America, with some glaciers shedding ice faster than any place in the world.

A recent study reported that the northern and southern Patagonia ice fields in particular are losing roughly 17 billion tons of ice each year. Los Glaciares National Park alone is home to around 50 large glaciers, but because of warming temperatures, almost all of these large ice masses have been shrinking over the last 50 years.

This level of glacial ice loss can be hard to fully imagine, but in 2017, Shauna-Kay Rainford, a PhD student at Pennsylvania State University in the United States and photographer of this featured image, got a first-hand glimpse of Patagonia’s changing landscape.

“Ensconced between the granite boulders I felt like I was at a pivotal moment of continued change,” said Rainford. “While the peaks of Mt. Ritz Roy remain and will likely remain tall and majestic, with each passing year the glacier continues to retreat further towards the peak and the glacial lake continues to expand more and more.”

Rainford had reached this scenic yet tragically ephemeral view after a strenuous hike up the mountain. “It was very emotional to think about what this view will look like in the future if I should ever visit the mountain again,” Rainford recalls. “It is always striking to be confronted with the adverse consequences of human actions.”

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: A pink and blue evening

Imaggeo on Mondays: A pink and blue evening

At sunset, the light travels a longer path in the atmosphere to reach our eyes than when the sun is high in the sky. At this time of the day, the light is more subject to scattering, as it interacts with more air (molecules and particles) before reaching our eyes, which explains why the sun is much less luminous and can be observed directly without being dazzled.

The sun appears redder because among the visible colours it emits, the blue radiation has been scattered by air molecules before this blue light reaches the observer. Indeed, the Rayleigh scattering theory says that the blue light (wavelength near 400 nm) is 16 times more scattered than the red light (wavelength near 800 nm). So the blue light is deviated outside the sun direction and only the remaining red light reaches the observer looking in the sun direction. This phenomenon also gives the blue colour of the sky when we look elsewhere than the direction of the sun.

Clouds consist of particles of liquid or solid water that are much larger than air molecules. It is then the Mie scattering theory that applies. This scattering favors no colour, which explains the milky colour of the clouds during the day. The clouds have the same colour of the solar radiation that strikes them. They therefore take a red colour at sunset and sunrise.

The night I took this photo, the beauty of the show was tinged with sadness: I came to the Pic du Midi Observatory in the Pyrenees (2800 m altitude) to observe the stars, not the clouds! This night of stars observation was a very great birthday present from my lab colleagues.

Luckily, the ceiling of the cloud layer lowered a little and the night was clear enough. The next morning, at dawn, the sea of ​​clouds confined in the valleys also offered a grandiose spectacle.

By Claudine Vanbauce, Université de Lille, Laboratoire d’Optique Atmosphérique, France

If you pre-register for the 2019 General Assembly (Vienna, 07–12 April), you can take part in our annual photo competition! From 15 January until 15 February, 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 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/.