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Imaggeo on Mondays: Crowned elephant seals do citizen science

Imaggeo on Mondays: Crowned elephant seals do citizen science

In the Southern Ocean and North Pacific lives a peculiar type of elephant seal. This group acts like any other marine mammal; they dive deep into the ocean, chow down on fish, and sunbathe on the beach. However, they do all this with scientific instruments attached to their heads. While the seals carry out their usual activities, the devices collect important oceanographic data that help scientists better understand our marine environment.

The practice of tagging elephant seals to obtain data started in 2004, and today equipped seals are the largest contributors of temperature and salinity profiles below of the 60th parallel south. You can find all sorts of data that has been collected by instrumented sea creatures through the Marine Mammals Exploring the Oceans Pole to Pole database online.

The female elephant seal, pictured here at Point Suzanne on the eastern end of the Kerguelen Islands in the Southern Ocean, is a member of this unusual headgear-wearing cohort. This particular seal had been roaming the sea for several months with the device (also known as a miniature Conductivity-Temperature-Depth sensor) on her head. As the seal dove hundreds of metres below the sea surface, the instrument captured the vertical profile of the area, recording the ocean’s temperature and salinity, as well as chlorophyll a fluorescence and concentrations. When the seal resurfaced, the sensor sent the data it had accrued to scientists by satellite.

Etienne Pauthenet, a PhD student at Stockholm University who was involved in a seal tagging campaign, had a chance to snap this photo before tranquilising the seal and retrieving the tag.

Using elephant seals and other marine mammals to collect data gives scientists the opportunity to analyse remote regions of the ocean that aren’t very accessible by vehicles. Studying these parts of the world are important for gaining insight on how oceans and their inhabitants are responding to climate change, for example. With the help of data-gathering elephant seals, researchers are able to amass in situ measurements from regions that previously had been hard to reach, apply this data to oceanographic models, and make predictions on ocean climate processes.

While gathering data via elephant seals are crucial to oceanographic research, Pauthenet explains that the practice is sometimes quite difficult. “It can be complicated to find back the seal, because of the Argo satellite signal precision. The quality of the signal depends on the position of the seal, if she is lying on her back for example, or if she is still in the water.”

While on the research campaign, Pauthenet and his colleagues were stationed at a small cabin on the shore of Point Suzanne and they walked the shore every day in search of the seal, relying on location points transmitted from a VHF radio. After seven days they finally located her and removed her valuable crown. The seal was then free to go about her business, having given her contribution to the hundreds of thousands of vertical profiles collected by marine mammal citizen scientists.

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.

Imaggeo on Mondays: Science in the Arctic trenches

Imaggeo on Mondays: Science in the Arctic trenches

Pictured here are climate scientists processing ice core samples in the East Greenland Ice-core Project (EastGRIP) science trench 10 m under the surface of the Greenland ice cap.

The trenches of this ice core camp require minimum building materials, utilising giant inflatable balloons that are dug in and covered with snow. The snow is left to compact for a few days, thereafter leaving back an arch-shaped underground trench ideal for ice core processing activities.

At this site, an international research consortium of ten countries led by the Center for Ice and Climate at the University of Copenhagen is aiming to retrieve an ice core from the surface of the Northeast Greenland Ice Stream, a fast-moving ribbon of ice within the Greenland Ice Sheet (GIS), all the way to the bedrock (approx. 2500 m).

Contrary to previous ice coring sites from the ice divide of the GIS, the EastGRIP site is a very dynamic place with a surface velocity of 55 m/year. Ice streams are responsible for a significant amount of the mass loss from the GIS, however their properties and behaviour are currently poorly understood. Having a better understanding of the streams’ features will allow for more accurate estimates of how the GIS accumulates and loses ice under current conditions as well as in warmer climate scenarios.

In order to understand the behavior of the site better, scientists carry out a series of state-of-the-art measurements on the ice core. They examine the physical properties and grain structure of the ice, as well as palaeoclimatic parameters, such as water isotopic ratios, gas concentrations and impurities. This research is often run by novel analytical methods that were specially developed in-house by members of this project. This constitutes a massive effort in terms of ice core sampling and measuring, a large part of which takes place in the field.

In weather-protected trenches under the surface of the snow, scientists process the ice core, part of which is measured on site. The rest of the ice is flown out of camp and distributed to laboratories around the world. The trenches provide a stable temperature environment, a feature important for the quality of the ice core sample.

By the end of the 2017 field season, the drill had reached a depth of 893 m and operations for 2018 are currently well under way. It is possible to follow the camp’s daily activities at the field diaries section here.

By Vasileios Gkinis, Center for Ice and Climate at the University of Copenhagen

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/.

How to make a planet habitable

How to make a planet habitable

Exoplanets without plate tectonics could harbour life, contrary to previous belief

For a planet to be habitable, it needs a stable climate. On Earth, the movement of tectonic plates ensures old crust is recycled and new crust is created and weathered. This cycling of rock consequently overturns the planet’s carbon, which keeps the climate in check.

While we have plate tectonics on Earth, many other rocky planets have what is called a ‘stagnant lid’. In this system, there is one solid plate wrapped around the planet, and the mantle circulates beneath it. The same recycling processes found on Earth don’t occur in these stagnant lid planets, preventing regulation of the carbon cycle and generating an inhospitable climate, or so scientists thought.

It is often claimed that plate tectonics is a requirement for a habitable climate, but research presented at the EGU General Assembly in Vienna suggests that some of these stagnant lid planets may be habitable after all.

Volcanic activity on stagnant lid planets could provide enough fresh rock for weathering to operate like it does on Earth, suggests Bradford Foley, a geologist from Pennsylvania State University in University Park, Pennsylvania. This means that simply burying the crust by lava flows could recycle enough CO2 to regulate the climate.

In their early history, the rocky surfaces of stagnant lid planets release gases that form an atmosphere. These young planets are also peppered with volcanoes that produce fresh, weatherable rock. Combined, these processes create a carbon cycle and, if the conditions are right, they can maintain a stable climate for long periods of time.

By modelling processes on stagnant lid planets that are similar in size to Earth, Foley was able to work out what conditions would create a habitable climate. The balance lies in striking the right amount of degassing, the process in which volcanoes release gas into the atmosphere. Not enough would lead to full surface glaciation, as too thin an atmosphere would make the planet extremely cold. On the other hand, too much degassing would generate a thick, CO2-rich atmosphere, leading to an incredibly hot environment.

There are two planetary budgets to take into account: carbon and heat. “We found a sweet spot, around Earth’s total amount of carbon to an order of magnitude less than that,” says Foley. That’s about 10 times less carbon than there is in Earth’s atmosphere, mantle and crust combined. Much lower, and there’s not enough of an atmosphere to keep the planet warm.

The other important consideration is the planet’s heat budget. As radioactive elements decay, they produce heat, and the more of these heat-producing elements a planet has, the bigger its heat budget. If a stagnant lid planet has fewer heat-producing elements than Earth, volcanic activity dies off pretty quickly and the planet cools off. “Without volcanism, the planet would most likely freeze over,” Foley adds. The more heat-producing elements there are, the longer volcanism can last. This means that, potentially, habitable climates could last longer too.

“Planets with two to two and a half times the heat budget for Earth can have potentially habitable climates lasting for three to four billion years, plenty enough time for developing life,” Foley explains.

According to Foley, the model could be used to guide future exoplanet missions. If we know how old a planet is and have information on its heat budget we can work out its chances of being habitable, says Foley. Both of these can be worked out using observations from Earth and could be used to create new targets for planetary exploration.

Lena Noack, a planetary scientist and Junior Professor at Free University Berlin who was not involved in the study, shared her thoughts on the research: “it shows, even though plate tectonics would typically always be considered as a better indicator for habitability, stagnant lid planets do not need to be ruled out. A good example is Mars; it was locally habitable early on in its history, but if it would just be a little bit larger, of Earth size as in Foley’s study, it is not difficult to imagine that it would be quite a habitable place at present day.”

By Sara Mynott

References: 

Foley,  B. Climate Stability and Habitability of Earth-like Stagnant Lid Planets. EGU General Assembly. 2018. 

Foley, B. and Smye, A. Carbon cycling and habitability of Earth-size stagnant lid planetsarXiv:1712.03614v1. 2017.