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Geosciences Column: Using volcanoes to study carbon emissions’ long-term environmental effect

Geosciences Column: Using volcanoes to study carbon emissions’ long-term environmental effect

In a world where carbon dioxide levels are rapidly rising, how do you study the long-term effect of carbon emissions?

To answer this question, some scientists have turned to Mammoth Mountain, a volcano in California that’s been releasing carbon dioxide for years. Recently, a team of researchers found that this volcanic ecosystem could give clues to how plants respond to elevated levels of carbon dioxide over long periods of time. The scientists suggest that studying carbon-emitting volcanoes could give us a deeper understanding on how climate change will influence terrestrial ecosystems through the decades. The results of their study were published last month in EGU’s open access journal Biogeosciences.

Carbon emissions reached a record high in 2018, as fossil-fuel use contributed roughly 37.1 billion tonnes of carbon dioxide to the atmosphere. Emissions are expected to increase globally if left unabated, and ecologists have been trying to better understand how this trend will impact plant ecology. One popular technique, which involves exposing environments to increased levels of carbon dioxide, has been used since the 1990s to study climate change’s impact.

The method, also known as the Free-Air Carbon dioxide Enrichment (FACE) experiment, has offered valuable insight into this matter, but can only give a short-term perspective. As a result, it’s been more challenging for scientists to study the long-term impact that emissions have on plant communities and ecosystems, according to the new study.

FACE facilities, such as the Nevada Desert FACE Facility, creates 21st century atmospheric conditions in an otherwise natural environment. Credit: National Nuclear Security Administration / Nevada Site Office via Wikimedia Commons

Carbon-emitting volcanoes, on the other hand, are often well-studied systems and have been known to emit carbon dioxide for decades to even centuries. For example, experts have been collecting data on gas emissions from Mammoth Mountain, a lava dome complex in eastern California, for almost twenty years. The volcano releases carbon dioxide at high concentrations through faults and fissures on the mountainside, subsequently leaving its forest environment exposed to the emissions. In short, the volcanic ecosystem essentially acts like a natural FACE experiment site.

“This is where long-term localized emissions from volcanic [carbon dioxide] can play a game-changing role in how to assess the long-term [carbon dioxide] effect on ecosystems,” wrote the authors in their published study. Research with longer study periods would also allow scientists to assess climate change’s effect on long-term ecosystem dynamics, including plant acclimation and species dominance shifts.

Through this exploratory study, the researchers involved sought to better understand whether the long-term ecological response to carbon-emitting volcanoes is actually representative to the ecological impact of increased atmospheric carbon dioxide.

Remotely sensed imagery acquired over Mammoth Mountain, showing (a) maps of soil CO2 flux simulated based on accumulation chamber measurements, shown overlaid on aerial RGB image, (b) above-ground biomass (c) evapotranspiration, and (d) normalized difference vegetation index (NDVI). Credit: K. Cawse-Nicholson et al.

To do so, the scientists analysed characteristics of the forest ecosystem situated on the Mammoth Mountain volcano. With the help of airborne remote-sensing tools, the team measured several ecological variables, including the forest’s canopy greenness, height and nitrogen concentrations, evapotranspiration, and biomass. Additionally they examined the carbon dioxide fluxes within actively degassing areas on Mammoth Mountain.

They used all this data to model the structure, composition, and function of the volcano’s forest, as well as model how the ecosystem changes when exposed to increased carbon emissions. Their results revealed that the carbon dioxide fluxes from Mammoth Mountain’s soil were correlated to many of the ecological variables analysed. Additionally, the researchers discovered that parts of the observed environmental impact of the volcano’s emissions were consistent with outcomes from past FACE experiments.  

Given the results, the study suggests that these kind of volcanic systems could work as natural test environments for long-term climate research. “This methodology can be applied to any site that is exposed to elevated [carbon dioxide],” the researchers wrote. Given that some plant communities have been exposed to volcanic emissions for hundreds of years, this method could help paint a more comprehensive picture of our future environment as Earth’s climate changes.

By Olivia Trani, EGU Communications Officer

References

Cawse-Nicholson, K., Fisher, J. B., Famiglietti, C. A., Braverman, A., Schwandner, F. M., Lewicki, J. L., Townsend, P. A., Schimel, D. S., Pavlick, R., Bormann, K. J., Ferraz, A., Kang, E. L., Ma, P., Bogue, R. R., Youmans, T., and Pieri, D. C.: Ecosystem responses to elevated CO2 using airborne remote sensing at Mammoth Mountain, California, Biogeosciences, 15, 7403-7418, https://doi.org/10.5194/bg-15-7403-2018, 2018.

Imaggeo on Mondays: Hole in a hole in a hole…

Imaggeo on Mondays: Hole in a hole in a hole…

This photo, captured by drone about 80 metres above the ground, shows a nested sinkhole system in the Dead Sea. Such systems typically take form in karst areas, landscapes where soluble rock, such as limestone, dolomite or gypsum, are sculpted and perforated by dissolution and erosion. Over time, these deteriorating processes can cause the surface to crack and collapse.

The olive-green hued sinkhole, about 20 m in diameter, is made up of a mud material coated by a thin salted cover. When the structures collapse, they can form beautiful blocks and patterns; however, these sinkholes can form quite suddenly, often without any warning, and deal significant damage to roads and buildings. Sinkhole formations have been a growing problem in the region, especially within the last four decades, and scientists are working hard to better understand the phenomenon and the risks it poses to nearby communities and industries.

Some researchers are analysing aerial photos of Dead Sea sinkholes (taken by drones, balloons and satellites, for example) to get a better idea of how these depressions take shape.

“The images help to understand the process of sinkhole formation,” said Djamil Al-Halbouni, a PhD student at the GFZ German Research Centre for Geosciences in Potsdam, Germany and the photographer of this featured image. “Especially the photogrammetric method allows to derive topographic changes and possible early subsidence in this system.” Al-Halbouni was working at the sinkhole area of Ghor Al-Haditha in Jordan when he had the chance to snap this beautiful photo of one of the Dead Sea’s many sinkhole systems.

Recently, Al-Halbouni and his colleagues have employed a different kind of strategy to understand sinkhole formation: taking subsurface snapshots of Dead Sea sinkholes with the help of artificial seismic waves. The method, called shear wave reflection seismic imaging, involves generating seismic waves in sinkhole-prone regions; the waves then make their way through the sediments below. A seismic receiver is positioned to record the velocities of the waves, giving the researchers clues to what materials are present belowground and how they are structured. As one Eos article reporting on the study puts it, the records were essentially an “ultrasound of the buried material.”

The results of their study, recently published in EGU’s open access journal, Solid Earth, give insight into what kind of underground conditions are more likely to give way to sinkhole formation, allowing local communities to better pinpoint sites for future construction, and what spots are best left alone. This study and further work by Al-Halbouni and his colleagues have been published in a special issue organised by EGU journals: “Environmental changes and hazards in the Dead Sea region.”

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/.

Preprint power: changing the publishing scene

Preprint power: changing the publishing scene

Open access publishing has become common practice in the science community. In this guest post, David Fernández-Blanco, a contributor to the EGU Tectonics and Structural Geology Division blog, presents one facet of open access that is changing the publishing system for many geoscientists: preprints.

Open access initiatives confronting the publishing system

The idea of open access publishing and freely sharing research outputs is becoming widely embraced by the scientific community. The limitations of traditional publishing practices and the misuse of this system are some of the key drivers behind the rise of open access initiatives. Additionally, the open access movement has been pushed even further by current online capacities to widely share research as it is produced.

Efforts to make open access the norm in publishing have been active for quite some time now. For example, almost two decades ago, the European Geosciences Union (EGU) launched its first open access journals, which hold research papers open for interactive online discussion. The EGU also allows manuscripts to be reviewed online by anyone in the community, before finally published in their peer-reviewed journals.

This trend is also now starting to be reflected at an institutional level. For example, all publicly funded scientific papers in Europe could be free to access by 2020, thanks to a reform promoted in 2016 by Carlos Moedas, the European Union’s Commissioner for Research, Science and Innovation.

More recently, in late 2017, around 200 German universities and research organisations cancelled the renewal of their Elsevier subscriptions due to unmet demands for lower prices and an open access policies. Similarly, French institutions refused a new deal with Springer in early 2018. Now, Swedish researchers have followed suit, deciding to cancel their agreement with Elsevier. All these international initiatives are confronting an accustomed publishing system.

The community-driven revolution

Within this context, it’s no surprise that the scientific community has come up with various exciting initiatives that promote open access, such as creating servers to share preprints. Preprints are scientific contributions ready to be shared with other scientists, but that are not yet (or are in the process of being) peer-reviewed. A preprint server is an online platform hosting preprints and making them freely available online.

Many journals that were slow to accept these servers are updating their policies to adapt to the steadily growing increase of preprint usage by a wide-range of scientific communities. Now most journals welcome manuscripts hosted by a preprint server. Even job postings and funding agencies are changing their policies. For example, the European Research Council (ERC) Starting and Consolidator Grants are now taking applicant preprints into consideration.

Preprints: changing the publishing system

ArXiv is the oldest and most established preprint server. It was created in 1991, initially directed towards physics research. The server receives on average 10,000 submissions per month and now hosts over one million manuscripts. Arxiv sets a precedent for preprints, and now servers covering other scientific fields have emerged, such as bioRxiv and ChemRxiv.

Credit: EarthArXiv

EarthArXiv was the first to fill the preprint gap for the Earth sciences. It was launched in October 2017 by Tom Narock, an assistant professor at Notre Dame of Maryland University in Baltimore (US), and Christopher Jackson, a professor at Imperial College London (UK). In the first 24 hours after its online launch, this preprint server already had nine submissions from geoscientists.

The server holds now more than 400 preprints, approved for publication after moderation, and gets around 1,600 downloads monthly. The platform’s policy may well contribute to its success – EarthArXiv is an independent preprint server strongly supported by the Earth sciences community, now run by 125 volunteers. The logo, for example, was a crowdsourcing effort. Through social media, EarthArXiv asked the online community to send their designs; then a poll was held to decide which one of the submitted logos would be selected. Additionally, the server’s Diversity Statement and Moderation Policy were both developed communally.

Credit: ESSOAr

In February 2018, some months after EarthArXiv went live, another platform serving the Earth sciences was born: the American Geophysical Union’s Earth and Space Science Open Archive, ESSOAr. The approach between both platforms is markedly different; ESSOAr is partially supported by Wiley, a publishing company, while EarthArXiv is independent of any publishers. The ESSOAr server is gaining momentum by hosting conference posters, while EarthArXiv plans to focus on preprint manuscripts, at least for the near future. The ESSOAr server hosts currently 120 posters and nine preprints.

What is the power of preprints?

How can researchers benefit from these new online sources?

No delays:

Preprint servers allow rapid dissemination. Through preprints, new scientific findings are shared directly with other scientists. The manuscript is immediately available after being uploaded, meaning it is searchable right away. There is no delay for peer-review, editorial decisions, or lengthy journal production.

Visibility:

A DOI is assigned to the work, so it is citable as soon as it is uploaded. This is especially helpful to early career scientists seeking for employment and funding opportunities, as they can show and prove their scholarly track record at any point.

Engagement:

Making research visible to the community can lead to helpful feedback and constructive, transparent discussions. Some servers and participating authors have promoted their preprints through social media, in many cases initiating productive conversations with fellow scientists. Hence, preprints promote not only healthy exchanges, but they may also lead to improvements to the initial manuscript. Also, through these exchanges, which occur outside of the journal-led peer-review route, it is possible to network and build collaborative links with fellow scientists.

No boundaries:

Preprints allow everyone to have access to science, making knowledge available across boundaries.

The servers are open without cost to everyone forever. This also means tax payers have free access to the science they pay for.

Backup:

Preprint servers are a useful way to self-archive documents.  Many preprint servers also host postprints, which are already published articles (after the embargo period applicable to some journals).

Given the difference between the publishing industry’s current model and preprint practices, it is not surprising to find an increasing number of scientists stirring the preprint movement. It is possible that many of such researchers are driven by a motivation to contribute to a transparent process and promote open science within their community and to the public. This motivation is indeed the true power of preprints.

Editor’s note: This is a guest blog post that expresses the opinion of its author, whose views may differ from those of the European Geosciences Union. We hope the post can serve to generate discussion and a civilised debate amongst our readers.

Geosciences Column: Landslide risk in a changing climate, and what that means for Europe’s roads

Geosciences Column: Landslide risk in a changing climate, and what that means for Europe’s roads

If your morning commute is already frustrating, get ready to buckle up. Our climate is changing, and that may increasingly affect some of central Europe’s major roads and railways, according to new research published in the EGU’s open access journal Natural Hazards and Earth System Sciences. The study found that, in the face of climate change, landslide-inducing rainfall events will increase in frequency over the century, putting central Europe’s transport infrastructure more at risk.  

How do landslides affect us?

Landslides that block off transportation corridors present many direct and indirect issues. Not only can these disruptions cause injuries and heavy delays, but in broader terms, they can negatively affect a region’s economic wellbeing.

One study for instance, published in Procedia Engineering in 2016, examined the economic impact of four landslides on Scotland’s road network and estimated that the direct cost of the hazards was between £400,000 and £1,700,000. Furthermore the study concluded that the consequential cost of the landslides was around £180,000 to £1,400,000.

Such landslides can have a societal impact on European communities as well, as disruptions to road and railway networks can impact access to daily goods, community services, and healthcare, the authors of the EGU study explain.

Modelling climate risk

To analyse climate patterns and how they might affect hazard risk in central Europe, the researchers first ran a set of global climate models, simulations that predict how the climate system will respond to different greenhouse gas emission scenarios. Specifically, the scientists ran climate projections based on the Intergovernmental Panel on Climate Change’s A1B socio-economic pathway, a scenario defined by rapid economic growth, technological advances, reduced cultural and economic inequality, a population peak by 2050, and a balanced reliance on different energy sources.

They then determined how often the conditions in their climate projections would trigger landslide events specifically in central Europe using a climate index that estimates landslide potential from the duration and intensity of rainfall events. The index, established by Fausto Guzzetti of National Research Council of Italy and his colleagues, suggests that landslide activity most likely occurs when a rainfall event satisfies the following three conditions: the event lasts more than three days, total downpour is more than 37.3 mm and at least one day of the rainfall period experiences more than 25.6 mm.

The researchers also incorporated into their models data on central Europe’s road infrastructure as well as the region’s geology, including topography, sensitivity to erosion, soil properties and land cover.

Overview of a particularly risk-prone region along the lowlands of Alsace and the Black Forest mountain range: (a) location of the region in central Europe and median of the increase in landslide-triggering climate events for (b) the near future and (c) the remote future.

The fate of Europe’s roadways

The results of the researchers’ models suggest that the number of landslide-triggering rainfall events will increase from now up until 2100. Their simulations also find while that these hazardous rainfall events slightly increase in frequency between 2021 and 2050, the number of these occurrences will be more significant between 2050 and 2100.  

While the flat, low-altitude areas of central Europe will only experience minor increases in landslide-inducing rainfall activity, regions with high elevation, like uplands and Alpine forests, are most at risk, their findings suggest.

The study found that many locations along the north side of the Alps in France, Germany, Austria and the Czech Republic may face up to seven additional landslide-triggering rainfall events as our climate changes. This includes the Vosges, the Black Forest, the Swabian Jura, the Bergisches Land, the Jura Mountains, the Northern Limestone Alps foothills, the Bohemian Forest, and the Austrian and Bavarian Alpine forestlands.

The researchers go on to explain that much of the Trans-European Transport Networks’ main corridors will be more exposed to landslide-inducing rainfall activity, especially the Rhine-Danube, the Scandinavian-Mediterranean, the Rhine-Alpine, the North Sea-Mediterranean, and the North Sea-Baltic corridors.

The scientists involved with the study hope that their findings will help European policy makers make informed plans and strategies when developing and maintaining the continents’ infrastructure.