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Atmospheric Sciences

Imaggeo on Mondays: Subsurface meteorolgy in Iceland

Imaggeo on Mondays: Subsurface meteorolgy in Iceland

With a total length of about 2 km, the Surdsellir lava cave is part of the Hallmundarhraun lava field in western Iceland. The caves ceiling is partly broken in, forming entrances and windows towards the earths surface. On this day of typically Icelandic weather, meteorological conditions changed quickly between sun, clouds, rain and wind. While walking through the cave during a rain shower, the sun came out illuminating the raindrops falling into the cave.

Description by Annika Vogel, as it first appeared on imaggeo.egu.eu

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/.

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

September 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 stories

Latest IPCC report puts the oceans and cryosphere in focus

Last month the United Nations’ Intergovernmental Panel on Climate Change (IPCC) released a special report that details the current status of the oceans and icy regions of the planet, and assesses how these parts of the Earth will fare as the climate changes. The Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC for short) also projects how future changes to Earth’s oceans and ice will impact the global population.

“The open sea, the Arctic, the Antarctic and the high mountains may seem far away to many people,” said Hoesung Lee, Chair of the IPCC. “But we depend on them and are influenced by them directly and indirectly in many ways – for weather and climate, for food and water, for energy, trade, transport, recreation and tourism, for health and wellbeing, for culture and identity.”

The 1,170-page report is packed with scientific details that illustrate how the environment is responding to climate change and what our world may likely look like under different carbon emission scenarios. We’ve listed just a few of the report’s findings here:

  • “Small glaciers found in high mountain environments are projected to lose more than 80% of their current ice mass by 2100 under high emission scenarios.”
  • “Even if global warming is limited to well below 2°C, around 25% of the near-surface (3-4 meter depth) permafrost will thaw by 2100.”
  • “While sea level has risen globally by around 15 cm during the 20th century, it is currently rising more than twice as fast – 3.6 mm per year – and accelerating.”
  • “Sea level rise will increase the frequency of extreme sea level events, which occur for example during high tides and intense storms. Some island nations are likely to become uninhabitable due to climate-related ocean and cryosphere change.”
  • “Marine heatwaves have doubled in frequency since 1982 and are increasing in intensity.”

The key message of SROCC is that the world’s oceans are becoming warmer, more acidic and less productive, while melting glaciers and ice sheets are causing the sea level to rise. While we are already experiencing the consequences of these environmental changes, their future severity and impact on society is dependent on how much we reduce our greenhouse gas emissions, protect and restore ecosystems, manage our natural resource use, and plan for related risks.

Want to learn more about SROCC? You can check out Carbon Brief’s explainer piece that delves further into the details.

Hurricane-heavy September

The Atlantic hurricane season is usually the most active during the month of September, and this year several powerful cyclones have inflicted heavy damage on a number of coastal communities.

Hurricane Dorian destruction in Bahamas on September 2, 2019. (U.S. Coast Guard photo courtesy of Coast Guard Air Station Clearwater)

Last month, Hurricane Dorian broke records as the strongest cyclone of the season so far, and the second strongest Atlantic hurricane on record, with sustained winds reaching 300 km an hour. In its early stages, Dorian hit the Windward Islands and the US Virgin Islands, but it made the biggest impact on the Bahamas as a Category 5 hurricane. For more than 36 hours, the storm slowly dragged across the Great Abaco and Grand Bahama islands, unleashing severe wind, rain and storm surge. The American Red Cross reported that more than 13,000 houses (nearly half of the islands’ residences) were destroyed as a result. The official death toll across the country is 56, and at least 600 people are still reported missing as of 27 September.

Another notable September storm includes Tropical Storm Imelda. While Imelda’s winds were relatively slow (65 km an hour), the storm was the seventh-wettest storm on record in the United States, releasing more than a metre of rain onto southeast Texas. At least two people died from the event, and more than 1,000 high-water rescues and evacuations were made.

Hurricane Lorenzo is the latest storm to catch media attention. The storm reached Category 5 status in the central Atlantic on 28 September and was listed as the strongest hurricane on record this far north and east in the Atlantic basin. The US National Hurricane Center has reported that the storm, now a Category 1 hurricane, is passing through Portugal’s Azores Islands and is projected to make its way north to Ireland and the UK by the end of the week. While the storm’s intensity has weakened, the hurricane is still very dangerous. In the Azores Islands, Ireland and the UK, local authorities and residents have been preparing for severe weather conditions, including heavy rain and strong wind.

This graphic shows an approximate representation of coastal areas under a hurricane warning (red), hurricane watch (pink), tropical storm warning (blue) and tropical storm watch (yellow). The orange circle indicates the current position of the center of the tropical cyclone. The black line, when selected, and dots show the National Hurricane Center (NHC) forecast track of the center at the times indicated. (Credit: NOAA National Hurricane Center)

Many scientists estimate that, as the climate changes, hurricanes and storms will likely be slower, wetter and more intense.

What you might have missed 

Is ‘The Blob’ back? 

Last month news outlets have reported that a large expanse of the northeast Pacific Ocean has been experiencing unusually warm temperatures, in some places as much as 3°C higher than average records. Stretching from the Gulf of Alaska to the Hawaiian Islands, the marine heatwave is currently the second largest on record in this region in the last 40 years.

The US National Oceanic & Atmospheric Administration noted that the current heatwave resembles the early stages of ‘The Blob,’ a massive heatwave that first formed in 2014 and persisted for three years. This earlier heatwave was connected to several ecological disturbances, including large harmful algal blooms, whale entanglements, coral bleaching, sea lion malnourishment, and many fishery disasters. Scientists fear that if this new heatwave does not dissipate soon, the event could lead to similar consequences.

Sea surface temperature anomaly maps show temperatures above normal in orange and red. (Credit: NOAA)

An icy expedition

Also last month, an international team of polar scientists have launched the largest Arctic research expedition in history. On 20 September, the German research vessel Polarstern set off on a journey to the Arctic, where it will spend an entire year trapped in sea ice, allowing researchers to observe the region’s climate system. The project, known as MOSAiC (Multidisciplinary Drifting Observatory for the Study of Arctic Climate), will involve more than 300 scientists from 19 countries.

The vessel is expected to move with the natural ice drift towards the Atlantic as the year progresses, collecting valuable information on the Arctic atmosphere, sea ice, ocean, ecosystems and biogeochemistry. “We will go and do science wherever the ice might carry us,” said chief scientist Markus Rex, an atmospheric scientist at the Alfred Wegener Institute, to Nature News & Comment. Researchers hope that the data will give an updated comprehensive look into the current state of the Arctic, allowing climate models to make better estimations of the region’s future.

Other noteworthy stories

The EGU story

This month, we have launched a short survey for EGU members to provide input on what they value from EGU, the results of which will help ensure that we remain responsive to what our members want. This is particularly important in a member-led organisation like the EGU. If you are an EGU member, we’d ask you to take 5-10 minutes to give feedback on EGU and its activities.

In General Assembly related news, we have opened applications for the third edition of our Artists in Residence programme. The programme is most attractive for scientist-artists, especially those already familiar with, and interested in, the EGU General Assembly. Applications are accepted until 1 December.

Finally, a note from the EGU Executive Secretary Philippe Courtial: “After 8 successful years at the EGU office, EGU Media and Communications Manager Bárbara Ferreira has decided to give a new orientation to her career. We would like to thank her for her tireless efforts and we wish her all the best for her future career.”

And don’t forget! 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: how short-term storms can impact our landscapes

Imaggeo on Mondays: how short-term storms can impact our landscapes

In the Sierra de Aconquija, a mountain range in the southern Central Andes of Argentina, strong storms often come and go at a moment’s notice, but they can have a long-lasting impact on the Earth’s surface.

The thunderstorm cell featured in this photo formed in less than half an hour, giving all those nearby only a few minutes to take cover. Mitch D’Arcy, a geomorphologist and postdoctoral researcher at the University of Potsdam and the GFZ German Research Centre for Geosciences, had the opportunity to witness this storm (and snap this picture!) while carrying out field work in the area.

“It was a spectacular experience, pouring heavy rain onto a very localised part of the mountain range, but it was also a hazard because the storm was quickly moving towards us with a lot of lightning. Without any trees around, we were likely targets for lightning strikes!” said D’Arcy. Luckily, he and his colleagues were able to find shelter in their truck while the huge downpour passed over them.

These kinds of thunderstorms are short-lived, but have intense precipitation rates. In this case, the temperature dropped by 14 degrees Celsius, and the storm was accompanied by heavy hail and lightning. And while these natural hazards are transient, they can have a long-term impact on the region’s landscape. Severe storms are capable of triggering landslides and floods and can relocate large amounts of sediment and debris in a short period of time.

D’Arcy is part of an international research programme called StRATEGy (Surface processes, Tectonics and Georesources: The Andean foreland basin of Argentina), which looks into how past and present climate change makes a mark on the terrain of the Argentine Andes, among other topics.

This research is essential for understanding and predicting how human-caused climate change will alter weather patterns and impact surface processes (such as how quickly sediments are eroded and transported across landscapes), according to D’Arcy. Having a better understanding of these surface processes and their sensitivity to the climate could help scientists better inform the public about how to prepare for natural hazards, such as flooding, erosion and landslides.

D’Arcy notes that it’s also important to assess how climate and weather trends will impact the sedimentary record, since it is one of the only physical records that scientists can use to examine how the Earth’s surface has change through time.

“North-western Argentina is a fascinating place to study how climate change affects surface processes, because it has experienced pronounced and abrupt changes in hydroclimate through time,” said D’Arcy. Their research has found that even subtle changes in the region’s climate have produced large changes to the surface environment, impacting how rivers take shape and how sediments move.

For example, while the Sierra de Aconquija is a semi-arid environment today, more than 12,000 years ago it used to be much wetter as a result of global climate changes. In fact, back then the mountain range was covered in glaciers and many of the basins were filled with lakes.

“It’s really important that we understand how different landscapes function and how they react to changes in climate. When we look at places like the southern Central Andes in Argentina, we find that the landscape records interesting signatures of ancient climate changes in Earth’s past. However, one of the big questions we still don’t have a good answer to, is how important are these very intense but rare storms for shaping landscapes and creating the sedimentary record from the geological past,” said D’Arcy.

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/.

Conversations on a century of geoscience in Europe: Part 1

Conversations on a century of geoscience in Europe: Part 1

When you think about the last century of geoscience, what comes to mind? Perhaps Alfred Wegener’s theory of continental drift? Or Inge Lehmann’s discovery of Earth’s solid inner core?

Over the last 100 years, geoscientists have made incredible contributions to our understanding of the Earth, the solar system, and beyond. The science community has explored uncharted territory, challenged previously held conceptions, provided vital information to policymakers, worked to address societal challenges, and put forth paths for sustainability. Through the years, researchers have also worked to promote diversity, inclusion, transparency, and accessibility in the geosciences. Many Europe-based scientists have been at the forefront of these advances.

Inspired by the centennials of the American Geophysical Union (AGU) and the International Union of Geodesy and Geophysics (IUGG), which were both founded in 1919, we would like to highlight Europe’s role in shaping the geosciences and the great achievements of European geoscientists within the last century.

In this series of interviews, scientists across different disciplines and scientific fields reflect on the last 100 years of Earth, space and planetary sciences in Europe and share their perspectives on the future:


Anne-Marie Treguier: Research Director at the French National Centre for Scientific Research and the European Institute for Marine Studies in the Ocean Physics Laboratory

The responsibility of geoscientists is huge. We must frame our scientific questions in the context of a wide range of future scenarios..

Read interview →

 

John Burrows: Professor of the Physics of the Ocean and Atmosphere and a Director of the Institutes of Environmental Physics and Remote Sensing at the University of Bremen

The history of discoveries in the geosciences is a fascinating story, involving unexpected and perplexing observations..

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Günter Blöschl: Head of the Institute of Hydraulic Engineering and Water Resources Management and Director of the Centre for Water Resource Systems of the Vienna University of Technology

As Heraclitus said, there is nothing permanent except change. Innovation needs to be permanent. We are in for an exciting future..

 

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Antje Boetius: Director of the Alfred Wegener Institute (AWI) Helmholtz Center for Polar and Marine Research and Professor of Geomicrobiology at the University of Bremen

When one reads the original reports and letters, we can learn how relevant expeditions and fieldwork were – and still are – for the international, collaborative spirit of the geosciences worldwide. The amazing thing is, in many ways we have remained explorers of our own planet Earth even today..

 

 

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Bernhard Diekmann, Head of the Research Unit Potsdam of the Alfred Wegener Institute (AWI) Helmholtz Center for Polar and Marine Research and Professor of Quaternary Geology at Potsdam University

During the last 100 years, the focus in geological research was understanding of processes in Earth’s interior and skin…The geosciences should no longer be seen as an individual field of research, but must be integrated into a holistic view of natural and social sciences..

 

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Interviews by Olivia Trani, EGU Communications Officer