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glacier

Imaggeo on Mondays: The glacier surviving climate change

Imaggeo on Mondays: The glacier surviving climate change

Human impacts on the climate are nowadays clearly discernible, and the changes to our climate that previously happened in geologic time scales are currently happening during the span of a human lifetime. Our planet is warming and temperature today is now more than 1°C higher than it was in the pre-industrial world and rises by about 0.15-0.2°C on average each decade. The dramatic effects of this rapid climate change are appearing right now: the increasing temperatures are melting glaciers and sea ice all over the world, shifting precipitation patterns and inducing extreme weather events, destroying habitats and forcing animals and people to migrate.

In this climate changing system, glaciers and sea ice represent very fragile elements. Glacier ice occupies about 10 percent of the world’s total land area and stores around 70 percent of the world’s total freshwater. When glaciers melt, freshwater is lost and flows into the seas raising the average global sea level. Since the surface of ice reflects sunlight, and thus heat, ice loss intensifies global warming. Despite this global glacier-melting trend, there are a few glaciers that are growing, one of which is the Perito Moreno Glacier. Scientists are not exactly sure why this glacier is advancing instead of retreating, but some hypothesize that precipitation shifts due to climate change or the glacier’s steep angle could be responsible for the phenomenon.

Located in southwest Santa Cruz Province of Argentina, the Perito Moreno Glacier is one of the region’s many glaciers, which collectively cover about half of the surface of Los Glaciares National Park, a UNESCO World Heritage Site. The glacier belongs to the Southern Patagonian Ice Field, which is the third largest freshwater reserve on the planet after the Antarctic and Greenland ice sheets. Perito Moreno Glacier descends from about 2100 metres in the Andes Mountains, down into the water of Lago Argentino at about 180 metres above sea level. It stretches for 30 km in length and 5 km in width (roughly equivalent in size to the Belgian capital Brussels) and rises 70 meters above the water surface of the lake. The glacier was formed during the last ice age, and is estimated to be 18,000 years old.

The current picture captures the front of the Perito Moreno Glacier from the Lago Argentino bank. By walking the last kilometres of the road which follows the lake shore from the entrance of the park to the main viewpoint, suddenly from between the green of the forest and the turquoise of the lake your sight is captured by the glacier: the white sleeping giant which lays quietly between the sides of the mountains. Coming closer and closer you start to feel the fresh air coming from the mouth of the glacier and hear its noisy breathing produced by the incessant ice cracking. From time to time you can also witness its mumbling, caused by calving ice slabs that fall into the water. The beauty of Perito Moreno Glacier is impressive, however its resistance against climate change is much more incredible. How long will this glacier still be able to resist?

By Magdalena Stefanova Vassileva, GFZ German Research Centre for Geosciences, 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: A walk at the glacier

Imaggeo on Mondays: A walk at the glacier

In 2012 I had the opportunity to help lead a teaching excursion to the Norwegian archipelago Svalbard. On this trip, geography students from the Ruhr-University of Bochum in Germany had the chance to learn more about the nature of this fascinating island.

In addition to Svalbard’s climatology and the wildlife, the region’s glaciology and geomorphology were the main topics we focused on. For example, we walked to the glacier ice, measured the glacier drainage flow and assigned various glacial debris accumulations (also known as moraines) to their genesis. Furthermore, PhD students from the local university showed us field experiments on how the region’s permafrost melts and wet soils slide downhill (also known as solifluction). We could see the giant glacier tongues with ice fronts at the sea level on a boat trip to the old coal mining town of Longyearbyen. The debris cover and the incredibly large medial moraine (debris that collects when two glaciers merge together) of the pictured glacier particularly impressed us.

We were astonished when the two polar bears came into sight after a short moment. Of course, we had secretly hoped to see polar bears on this excursion, but when it actually happened, not only the glaciers and the whole landscape seemed bigger, but also the wild nature of Svalbard got much more impressive. For me, my colleague André and my students this experience will be unforgettable.

By A. Martina Grudzielanek, Ruhr-University of Bochum, 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/.

 

July GeoRoundUp: the best of the Earth sciences from around the web

July GeoRoundUp: the best of the Earth sciences from around the web

Drawing inspiration from popular stories on our social media channels, major geoscience headlines, as well as unique and quirky research, this monthly column aims to bring you the latest Earth and planetary science news from around the web.

Major story

The world soaks up the sun

This summer our planet experienced the hottest June in recorded history, with the average global temperature reaching 16.4 °C, and July is on track to becoming the hottest month ever measured on Earth. And if you either live in or have been visiting Europe over the last few weeks, it sure feels like record-breaking heat.

In both June and July, several regions in Europe reached all-time temperature highs as warm air from northern Africa made its way through the continent. A rapid analysis done by researchers affiliated with the World Weather Attribution Network shows that human-caused climate change made the June heatwave at least five times more likely to happen. Furthermore, the scientists say in their report that “every heat wave occurring in Europe today is made more likely and more intense by human-induced climate change.”

Heatwaves this intense can put human health at risk and even be deadly in severe cases. A death toll reported that extreme heat Europe in the summer of 2003 led to more than 70,000 deaths throughout the continent.

The heatwave is now advancing towards Greenland, scientists report, and increased heat in the Arctic will likely lead to “another major peak in melt area,” said Twila Moon, a research scientist with the National Snow and Ice Data Center (NSIDC) in Colorado, US, to Live Science.

Simultaneous to the heatwave, a new study has reported that Earth’s current global warming is the only worldwide climate event to have happened in the last 2,000 years. While there have been notable climate events within the last few centuries, such as dramatic temperature changes from volcanic eruptions, the impact of these events were more regional rather than universal. In contrast, the study finds that modern climate change has affected 98 percent of the world.  “Absolutely nothing resembling modern-day global warming has happened on Earth for at least the past 2,000 years,” said the Atlantic.

50 years since one small step

20 July 2019 also marked the 50th anniversary of the first human steps on the Moon. In 1969, NASA astronauts Neil Armstrong and Buzz Aldrin landed on the Moon’s surface as part of the Apollo 11 Mission, revolutionising our understanding of our closest cosmic neighbor. For the 21 hours and 36 minutes on the lunar landscape, Armstrong and Aldrin reported field observations, installed instruments for multiple experiments, and gathered more than 20 kilograms of rock and dust samples.

Since then, scientists have made several discoveries from the data collected during the Apollo 11 Mission. For example, the rocks brought back from the Moon were determined to be about 4.5 billion years old, not much older than the Earth. Geoscientists also found that rocks from the Moon were very similar chemically to those on Earth, suggesting that the two bodies could have evolved in tandem from a large impact event, a leading theory also known as the giant-impact hypothesis.

Lunar Module pilot Buzz Aldrin photographed during the Apollo 11 extravehicular activity on the moon. Aldrin had just deployed the Early Apollo Scientific Experiments Package. In the foreground is the Passive Seismic Experiment Package; beyond it is the Laser Ranging Retro-Reflector (LR-3). Credit: NASA

While operational, the lunar seismometers installed by Armstrong and Aldrin detected ‘moonquakes’ and revealed that the Moon has a relatively small solid core and a thicker crust compared to the Earths’ interior.

Armstrong and Aldrin also set up a Laser Ranging Retroreflector to precisely measure how close the Moon is to the Earth. The retroreflector is still operational to this day, and the data obtained from the experiment shows that the Moon is almost literally inching away from the Earth at 3.8 centimetres (1.5 inches) each year on average.

These examples are just some of the discoveries made following this mission, and scientists are still studying the samples and data obtained 50 years ago to learn more about the Moon, the Earth and the solar system.

“One of the biggest misconceptions is that the Apollo samples aren’t being studied anymore, and that the Apollo samples only tell us about the moon,” says Ryan Zeigler, Apollo sample curator at the Johnson Space Center, in Science News.

What you might have missed

A new study published in July reported that tidewater glaciers, ones that flow from land to sea, could be melting much faster than previously thought. By analysing detailed measurements collected through radar, sonar and time-lapse photography, a team of researchers found that one Alaskan tidewater glacier is releasing a surprising meltwater from below the surface of the ocean.

“The melt rates that we measured were about 10 to 100 times larger than what theory predicted,” says lead study author David A. Sutherland, an oceanographer at the University of Oregon, in Scientific American.

The new findings could help scientists better understand how glaciers respond to global warming and how such glacial melt contributes to sea level rise and impacts local ecosystems.

Researchers studying LeConte Glacier in Alaska have found that its melt rate was 10 to 100 times larger than expected. Credit: US Forest Service, Carey Case

Other noteworthy stories

The EGU story

In July we are advertised another vacancy at the EGU Executive Office in Munich, Germany: EGU Communications Officer. The successful candidate will manage the EGU blogs and social media channels and be the office contact point for early career scientists.

Additionally, we are providing an EGU member with the opportunity to visit Brussels and work alongside a Member of the European Parliament (MEP) for a day. The pairing scheme will enable the selected EGU member to experience the daily work of an MEP, learn more about the role of science in policymaking, and potentially provide expertise on a science-policy issue. Interested EGU members should apply by 6 September.

Also in July, we have opened the call for candidates for EGU Union President, General Secretary and Division Presidents: if you’d like to nominate yourself or propose a candidate, you can do so by 15 September.

Finally, if you’d like to apply for financial support from the EGU to organise a meeting, make sure to submit an application by 15 August. This is also the deadline to submit proposals for Union Symposia and Great Debates at the EGU General Assembly 2020. The deadline for scientific sessions and short courses is 5 September.

Imaggeo on Mondays: Sand and snow on the Tibetan Plateau

Imaggeo on Mondays: Sand and snow on the Tibetan Plateau

Roughly 50 million years ago, the Eurasian and Indian continental plates began to crash into each other, dramatically changing the landscape of modern-day Asia. The force of the collision caused the Earth to scrunch together at the zone of impact, subsequently forming the Himalayan mountain range. However, to the north of the crash, a stretch of the Earth uplifted without bunching up or wrinkling; instead the clash formed an elevated flat surface five times as large as France, now known as the Tibetan Plateau.

The Tibetan Plateau is often called the ‘Roof of the World,’ as the region’s average elevation exceeds 4,500 metres and is home to the Earth’s highest peaks, including Mount Everest and K2. The plateau is also a crossroad for many different kinds of ecosystems and geologic features, including deep canyons, winding rivers, massive glaciers, boundless grasslands and alpine deserts.

This week’s featured image, taken by Monica Cardarilli, a risk and safety engineer at the Sapienza University of Rome in Italy, gives a snapshot into the plateau’s dynamic and diverse environment, where snow, water, soil and organic matter all make their mark on the landscape. “In this picture natural elements are expressed by the colors, like a painting where the whole exceeds the single parts in a mix of perceptions,” says Cardarilli.

The landscape of the plateau and the surrounding mountainous regions is also as fragile as it is diverse, and many scientists fear that climate change and other human activities are rapidly altering this corner of the Earth. For example, research suggests that the Tibetan Plateau is experiencing higher rates of warming compared to the global average, which has already caused concerning levels of glacier melt, flooding, desertification and grassland degradation in the area.

A recent report suggests that, due to climate change, at least one third of the glaciers situated within the plateau and the surrounding Hindu Kush-Himalaya (HKH) region will be lost from ice melt by the end of the century. This level of melting would have major consequences for the surrounding population, as more than 1.5 billion people rely on freshwater that stems from the region and many local communities would be threatened by severe flooding and lake bursts.

The report, undertaken by more than 200 researchers, warns that climate action is necessary to prevent even further melting in this region and avoid worse disasters.

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/.