GeoLog

EGU General Assembly 2017

GeoTalk: Hellishly hot period contributed to one of the most catastrophic mass extinctions of Earth’s history

GeoTalk: Hellishly hot period contributed to one of the most catastrophic mass extinctions of Earth’s history

Geotalk is a regular feature highlighting early career researchers and their work. Following the EGU General Assembly, we spoke to Yadong Sun, the winner of a 2017 Arne Richter Award for Outstanding Early Career Scientists, about his work on understanding mass-extinctions. Using a unique combination of sedimentological, palaeontological and geochemical techniques Yadong was able to identify some of the causes of the end-Permian mass extinction, which saw the most catastrophic diversity loss of the Phanerozoic. 

Thank you for talking to us today! Could you introduce yourself and tell us a little more about your career path so far?

Many thanks for inviting me here. I am currently working at the GeoZentrum Nordbayern, University of Erlangen-Nuremberg as a post-doc researcher.

I grew up in a small coastal town called Haiyang, east to the major city Tsingtao in North China. I moved to central China for university and majored in Geology at the China University of Geosciences (Wuhan) in 2004-2008.

This was followed by an exciting, 5 years split-site PhD program in which I spent two and a half years in China for field work and palaeontological training; half a year at Erlangen Germany for stable isotope and geochemical studies and the final 2 years at the University of Leeds, UK for training in sedimentology.

After my PhD, I successfully applied a fellowship from the Alexander von Humboldt Foundation and become an honourable Humboldtian.

In late 2015, two years after my PhD, I had 31 peer-reviewed papers including two in Science but was not fully prepared for the job market. It was already near the end of my fellowship. I only applied for one job—the O.K. Earl postdoc fellowship at the California Institute of Technology, US, but I didn’t get it. Completely unprepared for the situation, I was unemployed for about half a year.

I considered this the first setback in my early career. It taught me a valuable lesson; since I applied various research funding and fellowships and have never failed.

In early 2016, I was offered a postdoc position in a big project from the German Science Foundation (DFG forschergruppe) at Erlangen. I am very happy to be involved in the project and work again with many German and European colleagues.

Meet Yadong, pictured on fieldwork in the Himalayas. Credit: Yadong Sun.

During EGU 2017, you received an Arne Richter Award for Outstanding Early Career Scientists for your work understanding the end-Permian mass extinction. Could you tell us a little bit more about this period during Earth’s history?

The end-Permian mass extinction, which happened 252 million years ago, is the most devastating crisis seen in the Phanerozoic (the period of time during which there has seen life on Earth). However, the ultimate killing (or triggering) mechanism of this mass extinction is not fully understood and has been intensely debated for years.

Many fossil groups, in the ocean and on land were completely wiped out. The end-Permian mass extinction had profound influence on the evolution of life on Earth; such was the scale of the dying at this time. Extinction losses appear non-selective; virtually no groups escaped unscathed.

In the oceans some of the most abundant organisms such as the brachiopods (two-shelled organisms), radiolaria and foraminifera were almost (but not quite) eliminated whilst the rugose corals, tabulate corals, goniatites and trilobites were forever lost.

On land, the dominant herbivorous animals, the pareiasaurs, together with the gorgonopsids, the top predators, were lost. They lived in a world in which the dominant trees were the seed-bearing gymnosperms (e.g. glossopterids, gigantopterids, cordaites). All these groups, together with many other animals, including diverse insect groups, failed to survive the extinction.

After the mass extinction, the Early Triassic world was a time of extraordinary low diversity with the same monotonous communities found everywhere. For example, there is a 5 million year gap during which corals are not found in the rock record.

On land this included assemblages dominated by a shrub-like tree fern called Dicroidium, whilst the dominant animal was Lystrosaurus a pig-sized herbivore, belonging to a group called the dicynodonts.

In the world’s oceans, in the immediate aftermath of the extinction, it was the mollusks which occurred in the greatest numbers; a bivalve called Claraia was prolifically abundant just about everywhere.

It took an unusually long time (around 4-5 million years) for the biosphere to start recovering from the end-Permian mass extinction. This is much longer than after other mass extinctions and has lead scientists to speculate that the harsh conditions, responsible for the extinction in the first place, may have persisted for long afterwards.

At the same time, ocean chemistry was probably very different to modern day Earth. The oxygen levels in seawater were very low.

Despite the debate, what do scientists know about the causes of the end-Permian extinction?

The causes of the end-Permian mass extinction are, as a matter of fact, not perfectly understood. There are many different hypotheses. The key is to test the different hypotheses.

At the moment, we know with quite some certainty that anoxia (no free oxygen in seawater) and high temperatures both likely contributed to the end-Permian mass extinction.

Around the time of the extinction, there was massive volcanic activity in present day Siberia, known as the Siberian Traps. The lavas they left behind are known as the Siberian flood basalts. The eruption of the super volcano triggered global warming, voluminous volcanic CO2 inject to the atmosphere could lead to ocean acidification. This is because CO2 reacts with water and becomes carbonic acid (CO2 + H2O ↔ H2CO3). This is a very new and popular hypothesis to explain the mass extinction.

However, I myself am not fully convinced by the ocean acidification theory for the end-Permian mass extinction because there is a lot of evidence for carbonate over-saturated conditions at this time too. Carbonate saturated conditions mean that seawater contains very high concentrations of species such as CO32- and HCO3. They easily combine with Ca2+ and precipice as limestone and calcite cements. High concentrations CO32- and HCO3 have a buffering effect which inhibit the reaction forming carbonic acid. Therefore, it is not really possible to have ocean acidification and carbonate over-saturation at the same time. More detailed studies are needed to investigate this paradox.

In the past, some scientists proposed a sudden cooling or bolide impact as potential causes for the extinction, but these theories are no longer popular because of a lack of evidence.

In your presentation at EGU 2017 you spoke about how the extinction was accompanied by a rapid temperature rise, from 25 °C to 32 °C. How were you able to establish that such a significant temperature rise occurred?

I use oxygen isotope thermometry from conodonts: an extinct eel-like creature. Oxygen has two isotopes—18O and 16O. The ratio of the two isotopes in an animal is proportional to temperature from the oxygen isotope ratio of the water they ingest.

Reconstruction of temperatures for the end-Permian mass extinction is not easy since most shelly fossils died out. Those preserved are often subject to burial changes and therefore no longer preserve the original environmental information.

On the other hand, conodonts survived the end-Permian mass-extinction and are ideal for oxygen isotope analyses. They are very tiny (typically ~300 micro meter long) and consist of biogenic apatite. Apatite has 4 very robust P-O chemical bonds and very difficult to be altered after burial. Therefore, measuring oxygen isotope ratio of conodonts could help solved the problem.

However, because conodonts are so small and rare in rocks, I had to collect 2 tons of carbonate rocks dissolve the rock in acetic acid and pick the conodonts one by one under a binocular microscope, to get a big enough sample! It was a lot of work and required a lot of patience.

A Triassic conodont from south China. Credit: Yadong Sun.

That certainly sounds like painstaking work! Once the tedious task was completed, how were you able to link the temperature records you deciphered from the conodonts with the mass extinction?

All living creatures have a thermal threshold, also called thermal tolerance – the temperature range which they are able to tolerate to survive. It varies significantly amongst different groups. Most animals, on land or in the oceans, cannot live in environments that are consistently hotter than 47 °C. However, certain groups of desert ants and scorpions have developed special mechanisms and can survive 53 °C for a very brief time. Another example is the elevated seawater temperatures which contribute to high death rates of corals.

High temperatures supress photosynthesis. In most C3 plants, at temperatures above 35°C, photorespiration exceeds photosynthesis, wasting the energy generated by the plants.  in most C3 plants. Under such circumstances, C3 plants will stop growing and probably die shortly after. Maximum growth rates of single-celled algae in the ocean are normally achieved below 40°C.

A significant rise in seawater temperatures has many negative effects. One of them is that the amount of oxygen dissolved in seawater decreases as temperature rises, while animals use up more energy to perform even the simplest tasks. . This is one reason for which most marine groups prefer environments < 35°C.

These observations tie mass extinctions with temperature increase.

For our study, once the oxygen isotope ratios of conodonts are measured, we can use it in an equation to calculate the absolute temperature of the seawater at the time. The results show significantly higher ocean temperatures than today. We know the equation explains the relationship accurately because it was established in aquariums where scientists raise fishes in controlled temperatures. As temperatures are known, they measure the oxygen isotope of the water and fish teeth and established the oxygen isotope—temperature equation.

What do your findings mean for the current understanding of the causes of the mass-extinction?

This is an excellent question. There are quite some studies which postulate global warming as a potential killing mechanism for the end-Permian mass extinction. There is a link between the timing of the massive eruptions of the Siberia Large Igneous Province and the end-Permian mass extinction, which has led scientists to propose different warming scenarios. They are all correct, but they are not able to show direct evidence for their hypotheses or quantify the temperature change.

Our data show the worst-case scenario in terms of temperature rise and the mass mortality of species. This does not necessarily imply high temperatures killed everything because many adverse environmental conditions could trigger synergetic effects (for example low oxygen levels). Our study set an example for comparison.

Our results mean that rapid warming, such as what we are encountering at present, is truly worrying.

Yadong, thank you for speaking to me about your reasearch. As an award winner with an impressive career so far, what advice do you have for early career scientists?

Europe is probably the best place in the world for young scientists. It provides considerable fair funding opportunities and many possibilities to work with other scientists in the EU.

However, it is undeniable that fixed positions in academia are rare and highly competitive. It is always the best to go to meetings/conferences at least once a year to showcase your research, meet colleagues and seek collaboration opportunities.

Research projects nowadays are much more complex. Many tasks cannot be done by one person or one team. The success of a young scientist cannot be achieved without the support of senior scientists as well as the community.

Also don’t be shy to contact people and always be prepared for the job market. In the post-doc stage, if your project is very challenging, the best strategy is to work on some small projects on the side and keep publishing.

Interview by Laura Roberts Artal (EGU Communications Officer)

References

Sun, Y. Climate warming during and in the aftermath of the End-Permian mass extinction, Geophysical Research Abstracts, Vol. 19, EGU2017-2304, 2017, EGU General Assembly, 2017

EGU announces 2018 awards and medals

EGU announces 2018 awards and medals

From 8th to the 14th October a number of countries across the globe celebrate Earth Science Week, so it is a fitting time to celebrate the exceptional work of Earth, planetary and space scientist around the world.

Yesterday, the EGU announced the 49 recipients of next year’s Union Medals and Awards, Division Medals, and Division Outstanding Early Career Scientists Awards. The aim of the awards is to recognise the efforts of the awardees in furthering our understanding of the Earth, planetary and space sciences. The prizes will be handed out during the EGU 2018 General Assembly in Vienna on 8-13 April. Head over to the EGU website for the full list of awardees.

Nineteen out of the total 49 awards went to early career scientists who are recognised for the excellence of their work at the beginning of their academic career. Fifteen of the awards were given at Division level but four early career scientists were recognised at Union level, highlighting the quality of the research being carried out by the early stage researcher community within the EGU.

Nine out of the 49 awards conferred this year recognised the work of female scientists. Of those, four were given to researchers in the early stages of their academic career (at the Division level).

As a student (be it at undergraduate, masters, or PhD level), at the EGU 2017 General Assembly, you might have entered the Outstanding Student Poster and PICO (OSPP) Awards. A total of 57 poster contributions by early career researchers were bestowed with a OSPP award this year recognising the valuable and important work carried out by budding geoscientists. Judges took into account not only the quality of the research presented in the posters, but also how the findings were communicated both on paper and by the presenters. Follow this link for a full list of awardees.

Further information regarding how to nominate a candidate for a medal and details on the selection of candidates can be found on the EGU webpages. For details of how to enter the OSPP Award see the procedure for application, all of which takes place during the General Assembly, so it really couldn’t be easier to put yourself forward!

The EGU General Assembly is taking place in Vienna, Austria from 8  to 13 April. The call-for-abstracts will open in mid-October. Submit yours via the General Assembly website.

Academia is not the only route: exploring alternative career options for Earth scientists

Academia is not the only route: exploring alternative career options for Earth scientists

With more PhD and postdoc positions than there are tenured posts, landing a permanent job in academia is increasingly challenging. For some, years of funding and position uncertainty, coupled with having to relocate regularly is an unwelcome prospect. A changing job market also means that aspiring to the traditional, linear career path might be an unrealistic expectation. Skills acquired by those striving for an academic career (analytical skills, time and project management, persistence – writing a thesis requires it by the bucketload!) are highly valued in other job sectors too.

During a short course at the 2017 General Assembly, a panel of current and former geoscientists discussed their experiences in jobs both inside and outside academia.  They offered tips for how to pursue their careers paths and what skills served them best to get there.

In this blog post we profile each of their jobs and offer some of the highlights from the advice given during the session at the conference.


During the panel discussion Victoria stressed the importance of building a strong professional network, both inside and out of academia.

Victoria O’Connor (Technical Director at Petrotechnical Data Systems)

Victoria gained an undergraduate master degree in geology from the University of Liverpool in 2007. Since then, her career has focused around the oil industry, but has seen twists and turns, which have relied heavily on her building a varied skill set.

For almost six years after graduation, Victoria worked at Rock Deformation Research Ltd (RDR),  a spin out company from the University of Leeds, which was eventually acquired by Schlumberger. She held various roles throughout her time there, eventually becoming Vice President. The role relied heavily on her technical expertise as a structural geologist, as well as people management and organisational skills. In 2013, she moved to The Netherlands to work the Petrel technology team at Shell, where she managed various geoscience software development projects.

Her experience eventually enabled her to set up her own geoscience consulting company which was acquired by the PDS Group, through which she now manages the Geoscience products and services division, leading a 40 strong team of geoscientists and scientific software developers, developing cutting edge technologies for the oil and gas industry in collaboration with various academic institutions. In addition she also holds a visiting researcher position at the University of Leeds where she provides teaching and consultancy support. In addition, she also edits the European region AAPG newsletter.

During the panel discussion, Victoria stressed the importance of building relationships and developing a network of contacts. The benefits of building a strong professional network, both inside and out of academia are far reaching: job opportunities, joint collaborations, career development prospects. In her current role, she is developing technology with academic partners she first met over ten years ago at the University of Leeds.


getting on the career To get on the career ladder make sure you have a well written cover letter and CV, says Philip.

Philip Ball (Strategic Planning and Optimization Team & Geological Specialist [Rifted Margins] at Saudi Aramco)

Philip’s career certainly falls in the windy road category, rather than the linear path. It has involved a number of switches between industry and academic positions which have taken him all over the globe. His positions have always had an oil industry focus. He has lived through a number of market slumps, resulting in redundancies and an uncertain career path at times.

During the panel discussion Philip, highlighted adaptability and flexibility (skills certainly gained during research years) as a key to his success. Landing his first position was partly down to his willingness to be flexible.  In addition to being proactive, publishing, attending conferences and meetings, maintaining a network, never giving up is also critical. For example, he applied three times to Statoil between 2013 and 2015 before he managed to get an interview.

Before progressing onto a PhD, Philip enjoyed a short stint at the British Geological Survey and was a geologist for Arco British Ltd. Since gaining his PhD from Royal Holloway, University of London in 2005, Philip has held a number of positions at oil companies, including StatOil, ConocoPhillips, ONGC Videsh and Saudi Aramco.

His top tips, for getting on the career ladder is to make sure you have a well written cover letter and CV. This is critical whether applying for a student travel grant, research position or a position outside of the academic realm. Also do your research and do not expect chances to come to you. Use and visit the job boards online regularly to find positions in geoscience or other fields.


A career in the publications industry is a popular choice among researchers, like Xenia.

Xenia van Edig (Business Development at Copernicus.org)

Researchers are necessarily familiar with the world of academic publication (for more tips on how journal editors work take a look at this post we published recently), so it is hardly surprising this ends up being the chosen career of many former scientists.

Xenia Van Edig is one such example. Following an undergraduate in geography and PhD  in agricultural sciences at Georg-August-Universität-Göttingen, Xenia took a sidestep into the world of scientific coordination and management before starting her role at Copernicus (publishers of open access journals – including all the EGU publications – and conference organisers).

Project management was a skill set Xenia developed throughout her time as a junior researcher. It has been a pillar stone of her career outside of academia too.


Robert is an example of how a a hobby can become a new career direction.

Robert McSweeney (Science Editor at Carbon Brief)

Robert holds an MEng in mechanical engineering and an MSc in climate change. He worked for eight years as an environmental scientist for Atkins, a global design, engineering and project management firm.

For the past three years he’s been working as a science writer for Carbon Brief  – a website covering the latest developments in climate science, climate policy and energy policy – where he is now science editor. The role relies heavily on Robert’s communications skills, which scientists hone throughout their research career in the form of presentations at conference and to peers.

Robert highlighted how a hobby – in this case, writing – can become a new career direction. He also emphasised that scientists have a lot of opportunities to get involved with communicating their research, and commenting on others’, through blogs, Twitter, and developing extra materials to publish with new papers.


You don’t necessarily have to stick within your original field of expertise

Steven Gibbons (Senior Research Geophysicist at NORSAR)

Perhaps the best hybrid career for a researcher is to be able to continue to investigate, but not necessarily in an academic setting. It’s a nice compromise for those seeking a little more stability than life at traditional research institution might offer. But the notion shouldn’t be viewed with rose tinted glasses either: being an industry/foundation based scientists might mean less independence when it comes to selecting research topics and, often, securing funding is still an important part of the equation.

Nevertheless, it is can be a rewarding career which gives insights into a more commercial mindset and which draws on skills gain throughout academic research years, as Steven Gibbons described during the short course in April.

Crucially, his career trajectory highlights that you don’t necessarily have to stick within your original field of expertise. Steven has a PhD in core geodynamics and the Earth’s magnetic field, but now works as a geophysicist within the programme for Array Seismology and Test-Ban-Treaty Verification at NORSAR.

Steven has an undergraduate and PhD from the University of Leeds and has been working for NORSAR since 2002.


The EGU’s 2018 General Assembly, takes place in Vienna from 8 to 13 April, 2018. For more news about the upcoming General Assembly, you can also follow the offical hashtag, #EGU18, on our social media channels.

Cartooning science at EGU 2017 with Matthew Partridge (a.k.a Errant Science)

Cartooning science at EGU 2017 with Matthew Partridge (a.k.a Errant Science)

Most researchers are regular conference-goers. Tell a geoscientist you are attending the EGU General Assembly and they will most likely picture rooms full of people listening to a miriad of talks, many an hour chatting to colleagues old and new and you desperately trying to find your way around the maze that is the Austria Centre Vienna (where the conference is held). Describing your experiences to others (not so familiar with the conference set-up) can be a lot more tricky.

Cue Matthew Partridge, author of Errant Science, a blog which features (~) weekly cartoons and posts about the world of research.

With the aim to demystify what happens during a week-long conference, Matthew set himself the challenge of keeping a daily diary of his time at the 2017 General Assembly. As if that weren’t a tall enough order, the posts feature not only a witty take on his time in Vienna, but also cartoons! Whilst battling a huge sense of ‘impostor syndrome‘ (Matthew’s words, not ours), Matthew’s daily posts bring the conference to life.

With Errant Science (Matthew’s twitter alter ego is possibly better know) at the conference, we couldn’t pass up the opportunity of speaking to him. Video camera in hand, our press assistant, Kai Boggild, talked with Matthew about his motivations for blogging about the conference and that badger cartoon.

If you didn’t read Matthew’s posts while the conference was taking place in April, grab a coffee and get comfortable, they should be enjoyed repeatedly!