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Roundup of EGU Twitter Journal Club 2

13 Jul

The EGU’s Twitter Journal Club had its second virtual meeting yesterday, this time focusing on a paper from the EGU’s journal Biogeosciences, investigating the means by which microscopic life is sustained in the hostile aridity of the Atacama Desert. Read a full transcript of our discussion on our Storify page!

Vast expanse of Chile’s Atacama Desert, one of the most arid regions in the world. (source: Wikimedia)

The European Geosciences Union, through publishing house Copernicus Publications, publishes 14 peer-reviewed Open Access journalsBiogeosciences (BG, IF 3.587)  is an international scientific journal dedicated to the publication and discussion of research articles, short communications and review papers on all aspects of the interactions between the biological, chemical and physical processes in terrestrial or extraterrestrial life with the geosphere, hydrosphere and atmosphere. The objective of the journal is to cut across the boundaries of established sciences and achieve an interdisciplinary view of these interactions.

EGU Twitter Journal Club: Article 2

6 Jul

Time for the second edition of the EGU’s Twitter Journal Club, our interactive online discussion about a timely scientific article. Full details can be found here

This time, our article focuses on one of the most extreme environments on Earth, the Atacama Desert in Chile, and the method by which rock-dwelling microorganisms obtain their water. The Twitter discussion will take place on Thursday 12 July at 17:00 CEST (hashtag #egutjc2). Please email the EGU’s Science Communications Fellow Edvard Glücksman with further questions. Happy reading!

The Atacama Desert is one of Earth’s driest environments. (credit: Wikimedia)

Novel water source for endolithic life in the hyperarid core of the Atacama Desert
Biogeosciences, 9, 2275-2286, 2012

Abstract. The hyperarid core of the Atacama Desert, Chile, is possibly the driest and most life-limited place on Earth, yet endolithic microorganisms thrive inside halite pinnacles that are part of ancient salt flats. The existence of this microbial community in an environment that excludes any other life forms suggests biological adaptation to high salinity and desiccation stress, and indicates an alternative source of water for life other than rainfall, fog or dew. Here, we show that halite endoliths obtain liquid water through spontaneous capillary condensation at relative humidity (RH) much lower than the deliquescence RH of NaCl. We describe how this condensation could occur inside nano-pores smaller than 100 nm, in a newly characterized halite phase that is intimately associated with the endolithic aggregates. This nano-porous phase helps retain liquid water for long periods of time by preventing its evaporation even in conditions of utmost dryness. Our results explain how life has colonized and adapted to one of the most extreme environments on our planet, expanding the water activity envelope for life on Earth, and broadening the spectrum of possible habitats for life beyond our planet.

Questions to think about:
1. How would you summarise this article in a tweet?

2. The Atacama Desert is one of the driest environments on the planet. Can you think of others, and do you know of similar studies done there?

3. What is the link between the research presented here and our quest to find extraterrestrial life?

4. How could the methods presented here be improved in follow-up studies?

5. Do you see industrial applications for these findings?

Related media coverage
National Geographic Magazine
Sydney Morning Herald

The European Geosciences Union, through publishing house Copernicus Publications, publishes 14 peer-reviewed Open Access journalsBiogeosciences (BG, IF 3.587)  is an international scientific journal dedicated to the publication and discussion of research articles, short communications and review papers on all aspects of the interactions between the biological, chemical and physical processes in terrestrial or extraterrestrial life with the geosphere, hydrosphere and atmosphere. The objective of the journal is to cut across the boundaries of established sciences and achieve an interdisciplinary view of these interactions.

‘International Innovation’ meets EGU

13 Jun

International Innovation is a global dissemination publication that provides access to interviews, content and presentations for the wider scientific, technology and research communities. The magazine has, on various occasions, interviewed EGU personalities such as Ulrich Pöschl (Publications Committee Chair), a few division presidents and, most recently, EGU’s Executive Secretary, Philippe Courtial. Some of these EGU-related interviews are now available online.

  • Interview with Gert-Jan Reichard: “Biogeology has emerged over the past decade as one of the most important fields within the geosciences. Dr Gert-Jan Reichart, Division President of Biogeosciences at the European Geosciences Union offers his insight into the environmental challenges we face and how this research area is striving to address them”
  • Interview with Philippe Courtial: “Executive Secretary of the EGU, Dr Philippe Courtial, details the work of the Union in assisting scientists and improving the availability of accurate scientific data”
  • Interview with Michael Kühn: “Boldly trying to push science for solutions to solve the energy problems of tomorrow, Michael Kühn [EGU Division President of Energy, Resources and the Environment] is studying new approaches where renewables play a vital role”
  • Interview with Ulrich Pöschl: “The European Geosciences Union (EGU) is the world leader in interactive open access publishing and public peer review. We speak exclusively to Dr Ulrich Pöschl, the EGU Chair of Publication Committee, about the important work being done in the pursuit of knowledge sharing in the geosciences”
  • Interview with Denis-Didier Rousseau: “President of the European Geosciences Union, Division on Climate: Past, Present and Future, provides an insight into the ever expanding remit of this branch of the EGU”

(A few of these texts have also been reproduced with permission in GeoQ, the quarterly newsletter of the European Geosciences Union.)

Geosciences column: The evolution of the air

5 Jun

After a couple of months of absence, GeoLog is once again hosting the Geosciences column. This month we have no less than two posts highlighting recent research in the Earth sciences. In the first of this month’s columns, Amanda Gläser-Bligh writes about recent research on the regulation of the air published in the EGU journal Solid Earth.

If you’d like to contribute to GeoLog, please contact EGU’s Media and Commmunications Officer, Bárbara T. Ferreira at media@egu.eu.


What if the Earth had a thermostat that kept temperatures in the correct range to maintain life? In a recent paper published in Solid Earth, Euan Nisbet of London’s Royal Holloway and his collaborators propose just that.

Despite ups and downs in the atmospheric temperatures over geologic time, the Earth system seems to have maintained an equilibrium temperature of around 15°C. The global temperature appears to be able to correct itself up and down, much like an airplane constantly corrects its route, or a thermostat maintains a given temperature in a room. But how is the atmosphere being regulated on the planet, and who or what is selecting the temperature? An enzyme named rubisco seems to hold the answer.

What regulates the atmospheric composition of the Earth? (Photo: The sky from a plane after sunset, by Konstantinos Kourtidis. Distributed by EGU under a Creative Commons licence.)

Rubisco is one of the most commonly occurring enzymes on the planet: “When you eat your breakfast, you are most likely eating some rubisco,” Nisbet points out. The enzyme occurs in most green matter, having the important role of regulating CO2 intake to be used in photosynthesis, which in turn helps control atmospheric pressure by changing the CO2:O2 ratio.

The enzyme is responsible for the amount of carbon capture from CO2, and it is possible that rubisco’s selection of CO2 in preference to O2 controls the amounts of CO2 taken up by plants and algae, which is changing according to atmospheric conditions. This implies that rubisco itself determines the balance of CO2 and O2 in the air. The theory proposed by Nisbet and collaborators is that natural selection comes into play and causes the photosynthesizing organisms to pull down enough, but not too much, CO2 out of the atmosphere. This creates what is known as the Goldilocks effect: a planet that is not too hot and not too cold, but just right to sustain life.

There is a strong debate as to whether the atmospheric composition has been controlled by organic or inorganic elements. Nisbet and his team claim that while the system is biologically led, the process is a mixture of the two with inorganic chemistry working together with underlying biological trends.

Together with the changes occurring in the Sun, which was much weaker in the past, the greenhouse effect has reduced over time to compensate for this increase in solar temperatures. The suggestion is that rubisco evolution is the main driver of this shift and has created a stable system to maximize biological survival.

Additionally, because rubisco is a biological control, the response to challenging changes in atmospheric conditions (such as a massive volcanic outpouring of CO¬2) can occur rather rapidly when compared to inorganic processes, such as silicate erosion which also absorbs CO2.

To view what the scientific community had to say about the paper, check the article’s interactive discussion. ‘The regulation of the air: a hypothesis’ is the all-time most commented paper on Solid Earth Discussions.

By Amanda Gläser-Bligh, geologist and freelance writer

Publications by the EGU

10 May

The EGU is responsible for 14 Open Access journals, all freely available online

Since 2001, the EGU and Open Access publishing house Copernicus Publications has published a growing number of successful geoscientific journals. These include 14 peer-reviewed Open Access journals, of which 11 have a Thomson Reuters Impact Factor, placing them in the top echelon of their respective discipline. EGU also publishes a host of other materials available in paper and online. As a signatory of the Berlin Open Access Declaration (2003), the EGU is committed to making all their publications freely available.

The EGU’s Open Access scientific journals are:


Portuguese wines at risk due to climate change?

25 Apr

Today’s guest post comes from Eline Vanuytrecht from the Department of Earth and Environmental Sciences at KU Leuven, Belgium.

New study explores the impact of climatic change on the suitability of agricultural land in Portugal for wine growing

Wine is big business in Portugal. Viticulture or wine growing and the production of wine represent an important economic activity of the national agricultural sector. World famous are the Port Wine from the Douro Valley, the Vinho Verde from the Minho area, and different qualitative wines from the Alentejo region. The yearly revenue of the wine business is around 700 million euros.

Viticulture, as others sectors of agriculture, is extremely sensitive to local climatic conditions. Both the physiology of the vines and the quality of the wine are affected by several aspects of the local climate. For the Portuguese winemaking sector, it is of great interest to determine viticultural zones that give valuable information about the zone suitability for growing wine. H. Fraga and his colleagues from the Universidade de Trás-os-Montes e Alto Douro in Portugal performed extensive viticultural zoning for the whole country. The researchers identified suitable zones not only for the current situation, but in anticipation of global warming and associated climatic changes also for the future.

Portuguese wine is unique.

The research group determined a combined set of indices that identifies suitable zones for wine growing. The set consists of a humidity index, a thermal index (Huglin index) and a hydrothermal index. The humidity index is an index for the dryness of the soil’s root zone. This is vital because vineyards are vulnerable to prolonged periods of drought. The warmth index combines temperature and solar radiation information to identify suitable zones for wine growing. The hydrothermal index assesses excessive precipitation or humidity. The latter is important to exclude regions were the vulnerability to pests is high. The study results confirmed that, based on the indices, the vast majority of the Portuguese land is suitable for the production of excellent wines.

The image for the future is less bright. In a large part of the country, the suitability for wine growing decreases as a result of projected warmer and dryer climate in Southern Europe. Particularly in the southern and innermost region of Portugal, the thermal index is projected to increase, indicating excessive heats that may harm the vineyards. The humidity index is projected to decrease, as a result of projected extreme periods of drought for which especially South-Eastern Portugal is vulnerable. Even worse is that high impacts are found in the most important wine production regions of the country, thereby hitting the best Portuguese wines. The one redeeming feature is the projected decrease of the hydrothermal index in the future, an indication of the decreased potential damage of vineyards due to pests. Indeed, the drier conditions in the future create more hostile conditions for most pests.

The study of H. Fraga and colleagues highlighted the urgent need to develop good adaptation and mitigation measures for the Portuguese viticulture sector, including new wine varieties, genetic modification or adoption of advanced agricultural practices like irrigation, to cope with the changing climate in the region. It is not unlikely that within the coming decades a reshaping of the viticultural regions in Portugal is necessary and will bring different Portuguese wines on the table.

By Eline Vanuytrecht, KU Leuven

Geosciences column: Life in the aftermath of hydrothermal vents

8 Feb

Pioneering new study explores the structure and function of microbial communities at expired hydrothermal vent sites

Undiscovered lifeforms abound in Earth’s most seemingly inhospitable environments, as demonstrated by the recent discovery of bacteria living deep underneath the seafloor. An equally extreme environment can be found in the vicinity of hydrothermal vents, where water is expelled from the Earth’s crust at temperatures exceeding 400°C, after it percolates down through cracks formed at the intersection of tectonic plates. We now know that active vents teem with life, yet little is known about these habitats after venting eventually stops.

A study recently published in the Open Access journal mBio explored the inactive mineral deposits left behind by expired vents along the floor of the deep sea, showing they serve as long-term microhabitats for a succession of unique bacterial communities with potentially important roles within the broader marine food chain. This work is the first to demonstrate that life continues even as vent activity drops off.

Active hydrothermal vents and their distinctive chimneys (source: Wikipedia)

Searching for life at inactive vent sites: a genetic approach

The study, co-authored by researchers at the University of Southern California and the University of Minnesota, characterised microbial communities using advanced genetic sequencing techniques. The scientists obtained samples from expired vent chimneys on the East Pacific Rise, a tectonic plate boundary that runs along the Pacific Ocean, using the US Navy deep-sea submersible, Alvin — famous for its use in the exploration of the Titanic in 1986.

The genetic sequences provide a snapshot of the bacterial community at each sampling location. These data include the type of species present and, based on similarities with described species, their potential role within the local microbial food chain; in other words, what contribution their uptake of nutrients could make to the wider marine ecosystem. By obtaining similar data from active vents, the researchers could predict how relative counts of bacterial species change as venting ceases and the environment cools.

Microbes vital for marine ecosystems

The chimneys are formed by minerals carried by the vent emissions as they emerge from deep within the hot crust and collide with seawater. In the context of the study now published, they are of particular interest as long-term habitats for microbes because they are both widespread and resilient, remaining for up to 20,000 years following the expiry of a vent.

As venting ceases, the microbial community composition within chimneys changes drastically and the remaining bacterial biomass, the size of the community, grows by up to five times. Furthermore, the new community comprises several species that can take up and distribute essential elements back into their global cycles. In other words, not only does this study show that inactive vent sites contain unique communities of microbes, but the results also suggest these species are particularly important for the healthy functioning of the marine ecosystem.

Microbial communities serve as an important link in the global cycling of elements vital for life, such as carbon and nitrogen. Bacteria break down dead plant and animal matter, taking in carbon and thereby reintroducing it to the food chain when they are in turn consumed by larger organisms. Through a process known as nitrogen fixation, some bacteria also create – or ‘fix’ – nitrogen, an element necessary for the growth of plants.

Understanding these processes in the deep sea gives us unprecedented insight into how entire marine ecosystems function. “There are all these organisms down there making biomass, and that’s not at all accounted for in our carbon cycle,” commented senior author, Katrina Edwards, in an interview with OurAmazingPlanet.

Bacterial lifestyle shift

Apart from demonstrating the important ecological role of life at expired vents, this study also complements previous work by illustrating how the drastic environmental change that accompanies vent expiry favours organisms with an entirely different lifestyle. At active vent sites, bacteria get the energy they need to survive from the heat and content of the fluids coming from deep within the Earth. At inactive vents, the two most commonly found bacterial groups stay alive using a different mechanism, generating energy from the minerals freed up by the natural weathering of the chimneys. “Seeing the shift in the microbial population – seeing who actually came and left, was fairly illuminating for me,” said Edwards.

This exploratory study will be followed up by more work on the mechanisms of bacterial community succession, both at hydrothermal vent sites and also, as Edwards explains to AstroBio Magazine, in microbes existing beneath rock surfaces. The authors conclude by explaining that studies focusing on other microscopic species have yet to be undertaken, but may hold equally great potential in understanding the vital ecological contribution of deep-sea microorganisms.

By Edvard Glücksman, EGU Science Communications Fellow  

Imaggeo on Mondays: Lonely Tree

12 Dec

The Lonely tree. Image by Alexandre M. Ramos , distributed by EGU under a Creative Commons licence.

The photograph was taken near to Üetliberg in Switzerland. The Üetliberg mountain is close to Zurich and part of the Albis mountain range.

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.

EGU General Assembly 2012 Call for Papers

9 Nov

Abstract submission for the EGU General Assembly 2012 (EGU2012) is now open. The General Assembly is being held from Sunday 22 Apr 2012 to Friday 27 Apr 2012 at the Austria Center Vienna, Austria.

You can browse through the Sessions online.

Each Session shows the link Abstract Submission. Using this link you are asked to log in to the Copernicus Office Meeting Organizer. You may submit the text of your contribution as plain text, LaTeX, or MS Word content. Please pay attention to the First Author Rule.

The deadline for the receipt of Abstracts is 17 January 2012. In case you would like to apply for support, please submit no later than 15 December 2011. Information about the financial support available can be found on the Support and Distinction part of the EGU GA 2012 website.

Further information about the EGU General Assembly 2012 on it’s webpages. If you have any questions email the meeting organisers Copernicus.

Imaggeo on Mondays: Stretching to the Light

31 Oct

Stretching to the Lights, Bryce Canyon, Utah, USA. Image by Valeria Volpe, distributed by EGU under a Creative Commons License.

Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.