GeoLog
Olivia Trani

Olivia Trani

Olivia Trani is the Communications Officer at the European Geosciences Union. She is responsible for the management of the Union's social media presence and the EGU blogs, where she writes regularly for the EGU's official blog, GeoLog. She is also the point of contact for early career scientists (ECS) at the EGU Office. Olivia has a MS in Science Journalism from Boston University and her work has appeared on WBUR-FM, Inside Science News Service, and the American Geophysical Union. Olivia tweets at @oliviatrani.

Imaggeo on Mondays: How erosion creates natural clay walls

Imaggeo on Mondays: How erosion creates natural clay walls

The badlands valley of Civita di Bagnoregio is a hidden natural gem in the province of Viterbo, Italy, just 100 kilometres from Rome. Pictured here is the ‘wall,’ one of the valley’s most peculiar features, where you can even find the wooden structural remains of a trail used for agricultural purposes in the 19th and 20th centuries.

The photograph was taken by Chiara Arrighi, a post-doc research assistant at the University of Florence (Italy), in May last year after climbing roughly 200 metres from the bottom of the Chiaro creek valley. Trails in this region are not well traced or maintained, so she had to find her own way up among the chestnut woods. Once at the top, the trail becomes narrow and unprotected. “The inhabitants of the area still do not exploit this natural beauty as a tourist attraction,” said Arrighi. “In fact, nobody was on the trail, and the silence [was] unreal.”

Badlands are a typical geological formation, where grains of sand, silt and clay are clumped together with sedimentary rock to form layers, which are then weathered down by wind and water. The terrain is characterised by erosive valleys with steep slopes, without vegetation, separated by thin ridges.

Due to the slope’s steep angle and the clay’s low permeability, little water is able enter the soil. Instead water quickly flows across the surface, removing surface clay and carving into the slopes as it does so.

The morphological evolution of the clay slopes can be very rapid (for example, rock falls can occur quite suddenly after heavy rainfall) and occurs as a result of several physical mechanisms, such as mud flows, solifluction (slow movement of wet soil towards the bottom of the valley) and sliding.

During the evolution of the badlands, peripheral portions of the terrain made up of volcanic deposits (tuff cliffs) rose up from the landscape, bordered by nearly vertical slopes (called scarps). Many towns have been built on these erected hilltops, such as Civita di Bagnoregio.

By Chiara Arrighi and Olivia Trani

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

This month has been a whirlwind of Earth and space science news; the majority focusing on natural hazards. Powerful cyclones, earthquakes, and tsunamis have received significant coverage from the geoscience media. Quickly recap on an action-packed month with our overview:

On 14 September, Hurricane Florence, made landfall in the mid-Atlantic region of the United States, making first contact near Wrightsville Beach in North Carolina then traveling up the East Coast. By the time Florence had reached the US coastline, the cyclone’s sustained wind speed had dropped considerably, downgrading the hurricane from a category 4 to category 1 storm on the Saffir–Simpson scale.

This designation may sound mild, but as many scientists and journalists have pointed out, sluggish hurricanes are especially dangerous, since they are more likely to dump heavy rainfall over a relatively small surface area compared to faster storms that distribute their rainfall over more territory. This proved to be true for Hurricane Harvey, which dumped more than 150 centimetres of rain onto some areas of Houston, Texas.

Hurricane Florence’s record-breaking rainfall forced more than a million people to evacuate their homes, and experts estimate that the storm inflicted damages worth more than $38 billion (USD). The hurricane also produced very concerning environmental damages. In Wilmington, North Carolina, for instance, the the rainfall flooded a pit of coal ash at a power plant, releasing more than 1,530 cubic metres of ash, with much of it likely ending up in a nearby lake.

Across the planet, just one day following Hurricane Florence’s landfall, Super Typhoon Mangkhut wreaked havoc on southeast Asia, pounding the Mariana Islands, the Philippines, China, Taiwan, and Vietnam with strong wind and rain. Reaching wind speed over 240 kilometres per hour, Mangkhut is the most intense storm of the year so far. The New York Times created an interesting three-dimensional visual of the storm’s intensity, using NASA satellite data.

In addition to unleashing incredibly strong winds, the typhoon’s rainfall also triggered deadly landslides. Just outside of the city Baguio, which recorded more than 75 centimetres of rain, more than 40 gold miners were buried under a landslide that hit their bunkhouse.

Big storms like Hurricane Florence and Typhoon Mangkhut are expected to be more frequent in the future as our climate changes. And this stems from many factors; a recent article from the New York Times explains that, due to climate change, the world’s oceans are warming (fueling more hurricane formation), the atmosphere is holding more moisture (leading to wetter storms), hurricane wind speeds are slowing down (causing more concentrated rainfall), and Earth’s sea levels are rising (increasing the risk of flooding).

Last week, a 7.5-magnitude earthquake struck the Indonesian island of Sulawesi, sending a massive tsunami, with waves up to 6 metres high, into Palu Bay, causing massive devastation in the regional capital Palu and surrounding areas. Officials report that nearly 1,350 people have died from the earthquake and tsunami, and the death toll is expected to rise as rescue workers make their way towards more remote places. Scientists told BBC that “a combination of geography, timing and inadequate warnings meant that what happened in Palu was a worst case scenario.”

Map of the September 28, 2018 Palu, Indonesia Earthquake. Credit: USGS.

Indonesian aid workers and humanitarian relief envoys are currently working to provide supplies and assistance to the affected communities. At the same time, scientists are still puzzling over the tsunami’s strength, which caught many experts by surprise. This is because the earthquake’s behavior isn’t known for generating catastrophic tsunamis.

Powerful tsunamis are typically caused by earthquakes with vertical motion, where part of the seafloor juts forward, disturbing the water column and consequently sending massive waves to the coast. The 2004 Indian Ocean tsunami, for example, was caused by a 9.1 magnitude megathrust earthquake. On the other hand, last week’s quake is known as a ‘strike-slip earthquake,’ where the ground shifts horizontally. This kind of movement doesn’t move ocean water as dramatically.

“Some early calculations suggest a floor displacement of perhaps half a metre. Significant but generally insufficient to produce the waves that were recorded,” reported the BBC.

While it is too early to tell what exactly happened, scientists suspect that a number of factors could have played part in helping the tsunami gather strength. For example, underwater landslides have been known to trigger tsunamis of similar strength. Additionally Palu Bay’s narrow geometry could have amplified the waves’ height.

The underlying factors that contributed to the event will hopefully become more clear as scientists analyse the series of events in more detail.

What you might have missed

This month, the Japanase spacecraft Hayabusa 2 has sent three robots to the rocky surface of an asteroid near Earth, known as Ryugu. The spacecraft had successfully reached the asteroid this June, after travelling for more than three years. The craft first released two small devices, no bigger than frying pans, which tumbled around the rock’s surface and even sent digital postcards and a short video back home. A few days ago, Hayabusa 2 released a third rover, which will use a suite of different scientific instruments to collect data on the asteroid. “Hayabusa2 itself is likely to make the first of three touchdowns on the asteroid to collect samples later this month,” said Science Magazine.

Links we liked

  • StarTrek creators once said that Spock’s fictional home planet Vulcan orbited the 40 Eridani A star. Now scientists have found an exoplanet that fits the description.
  • Rediscovered: the 19th century geological drawings of Orra White Hitchcock, a pioneering female scientific illustrator
  • Researchers discover that kidney stones grow and dissolve much like geological crystals
  • We all know about lava volcanoes, but have you heard of ice volcanoes? New study suggests that cryovolcanoes have likely been erupting for billions of years on Ceres.
  • This new map of Antarctica is like ‘putting on glasses for the first time and seeing 20/20’

The EGU story

Last week, the EGU hosted its first science-policy dinner debate in Brussels. The event, ‘Horizon Geoscience: overcoming societal challenges, creating change’, was organised in collaboration with the European Federation of Geologists (EFG) and brought together geoscientists, policymakers and industry representatives. On the EGU website, we report on the outcome of the discussion and publish the key findings from the Horizon 2020 Geoscience Survey conducted earlier this year.

Panel members during the Horizon Geoscience dinner debate. From Left to right: Jonathan Bamber, John Ludden Lieve Weirinck, Jean-Eric Paquet and Vitor Correia

In the past few weeks, we have also issued three press releases highlighting research published in some of EGU’s open access journals. Follow the links to find out how bombing raids in the Second World War impacted the ionosphere, how glacial geoengineering could help limit sea-level rise, and what the point of no return for climate action might be.

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.

GeoTalk: Nilay Dogulu, Early Career Scientist Representative

GeoTalk: Nilay Dogulu, Early Career Scientist Representative

In addition to the usual GeoTalk interviews, where we highlight the work and achievements of early career researchers, this month we’ll also introduce one of the Division early career scientist representatives (ECS). They are responsible for ensuring that the voice of EGU ECS membership is heard. From organising short courses during the General Assembly, through to running and attending regular ECS representative meetings, their tasks in this role are varied. Their role is entirely voluntary and they are all active members of their research community, so we’ll also be touching on their scientific work during the interview.

Today we are talking to Nilay Dogulu, ECS representative for the Hydrological Sciences (HS) Division and past chair of the Young Hydrologic Society.

Before we get stuck in, could you introduce yourself and tell us a little more about yourself, your involvement with EGU and how you became interested in hydrology?

I am a PhD candidate at the Middle East Technical University (METU) in Ankara, Turkey, researching clustering methods for data-driven hydrology at the Water Resources Laboratory. This year I attended the General Assembly (GA) in Vienna for the fifth time in a row. Since 2014, the Assembly has been the one and only conference that I have persistently and willingly participated in. The Hydrological Sciences (HS) division’s scientific programme at the GA had a special role in shaping my career as a researcher, so I would like to share my journey in the hydrological sciences lightened up by the EGU GA and its HS community.

First, little about me. I am a civil engineer by training. I was a third year (BSc) student at METU (ODTU) when I took the course “Engineering Hydrology.” It was the first time I learned about the terms catchment, basin and hydrograph. In that very semester I had the opportunity to participate in the 5th World Water Forum in Istanbul. That was it. I was determined to specialize in water for my future career.

To broaden my understanding of hydrological processes and gain a critical view of the latest hydrology topics, I gathered the courage—as only a BSc student at the time—to attend the 6th National Hydrology Congress and the 2nd National Flood Symposium. Then a three-month internship at the State Hydraulic Works of Turkey introduced me to the wider community of hydrological sciences in the world.

My class notes from the Engineering Hydrology course back in March 2009 (Credit: Nilay Dogulu)

In Fall 2011, I joined the FLOODRisk Master to study floods, from modelling them to understanding their socio-economic effects. This two-years programme enriched my academic background on flood risk management and provided me with different insights into water-related problems.

Could you tell me about your first experience with the EGU General Assembly?

With EGU HS Division president Elena Toth (right) and president-elect Maria-Helena Ramos (left) at EGU 2018

The EGU GA brings together researchers from all around the world. The EGU Hydrological Sciences Division is EGU’s largest division with a diverse and comprehensive scientific programme at the GA, large enough to fill in the whole second (red) floor of the conference venue.

The EGU HS division is a great platform aimed at addressing current research challenges in hydrology. During the GA, one can follow up with the latest research on various topics within these areas and network with members (of all stages) of this great community. At the 2018 EGU GA, hydrological sciences programme had 2350 abstracts submitted to 91 HS-lead sessions (66 oral and poster sessions, 6 poster only sessions, 19 PICO sessions)—equivalent to 13.5% of total EGU GA submissions.

Given this, I was very motivated to experience the General Assembly for the first time! I submitted an abstract summarizing part of my MSc research—on predictive uncertainty estimation for flood forecasting using data-driven modelling techniques; and once it was accepted, I started to get ready for EGU and Vienna! Flight and accommodation booked, poster printed, weekly conference schedule prepared. This was the first poster presentation of my career and I was quite excited. Luckily, all went really well.

EGU Hydrological Sciences Division

I remember having a busy week at EGU 2014: from presenting my first poster, working on a manuscript with my co-authors, as well as attending project meetings, sessions on flood forecasting and flood risk management, and short courses organized by the Young Hydrologic Society (YHS).

There were many interested people visiting my poster and asking questions. There were many posters I visited too—I have to admit, sometimes I asked so many questions that the presenters thought  I was an OSPP Award judge.

Throughout the week I listened presentations, many of which were given by researchers I cited in my master’s thesis. Matching the papers with authors’ faces was amazingly so much fun! Moreover, I arranged a small meeting with my co-authors to discuss the manuscript draft (which has been later published in HESS) that we had only been working on remotely before then.

At the time, I was also working for the EU-FP7 project ASTARTE (Assessment, STrategy And Risk Reduction for Tsunamis in Europe). The EGU GA is an excellent time for research project teams, editorial boards of journals, etc. to schedule meetings.  ASTARTE team (26 partners from 16 countries) also took this opportunity to meet up to discuss the progress following the project’s first 6-months period. During this meeting, I presented one of the very important deliverables of the project which focused on tsunami resilience from a social sciences perspective.

On the Saturday after the conference there was the Vienna Catchment Science Symposium organized by the Vienna University of Technology Centre for Water Resources Systems. It proved to be a very enlightening symposium for a young hydrologist.

Sounds like a great first experience! How has your time at the GA changed over the years?

After enjoying the academic fun of EGU 2014, I wanted to come back to Vienna for EGU 2015. Another reason was that I was very curious why people were heading to the conference venue on the very last hours of the last day (Friday): I left around 5 pm and many people were coming out of metro!

METU Water Resources Lab researchers at EGU 2016

In 2015 I had one PICO presentation and two short course convenerships, How to write (and publish) a scientific paper in hydrology and Hydroinformatics for Hydrology. Both were co-organized with the Young Hydrologic Society and proved to be very successful!

Without any hesitation, I decided to attend EGU 2016 and EGU 2017 in the next years. Although I didn’t have any presentations in 2016, listening to presentations covering my research interests helped me stay updated and synthesise various perspectives on overarching problems in hydrology. The sessions kept me thinking about some questions that had been tingling my mind—which later became the research questions in my PhD thesis proposal.

At EGU 2017, my poster presentation was a literature review on application of clustering methods in hydrology, and actually it attracted more people than I expected. EGU poster sessions provide an excellent way to bring together early career researchers while they stand in front of their posters, paving the way for interesting discussions.

Memories from EGU 2017

My fifth year at the EGU GA last April was great too: including two posters, sessions to co-/convene, YHS events (from short courses to PICO sessions), the EGU ECS Representatives Workshop, YHS Hydrodrinks, the HS division meeting, medal lectures and many other activities. Being an experienced EGU GA participant, I also served as a mentor as part of the EGU mentoring programme designed to help novice conference attendees navigate their first EGU experience.

Almost forgot! On Friday evening, the conveners’ reception (and party, with a different theme every year) takes place at the ACV.

In addition to being an EGU ECS representative, you also are involved with the Young Hydrologic Society (YHS). Could you tell me more about this organisation and your role in YHS?

YHS is a bottom-up initiative that aims to help early career hydrologists interact and actively participate within the hydrological sciences community and beyond. We are a group of motivated PhDs and postdocs who enjoy serving our very own community, considering the needs and interests of young hydrologists.

The YHS is most actively involved with the EGU GA, where we organizing short courses, scientific sessions and social events. The full list of all events that YHS has organized for the EGU GA since 2013 can be found on the YHS webpage. The open call for session proposals for EGU GA 2019 has just closed (deadline 6 September) – there have been quite a number short course submissions (in cooperation with YHS) that will play a significant role in shaping the HS programme for ECSs. YHS Hydrodrinks event held annually at the EGU GA is now a 5-year-old tradition where we meet our new team members. If you are planning to come to EGU 2019, don’t miss the chance to meet fellow hydrologists at the Hydrodrinks (however, please note that this is not a sponsored event). Contributing to the academic and social development of early career hydrologists by organising activities at the EGU GA is a unique and rewarding experience, so get involved!

YHS Hydrodrinks at EGU 2014 (Credit: The waiter)

I joined YHS after meeting the team at EGU 2014. Since then I couldn’t help myself but contribute to the aims of the society in many ways—like organizing short courses at conferences (e.g. Hydroinformatics for Hydrology at the EGU GA), managing and contributing to the YHS Blog (Streams of Thought and Hallway Conversations), and acting as a Board member (secretary 2015-16, chair 2016-17).

Right: EGU 2018 Poster 1—Clustering approaches for analysing similarity in ungauged catchments: input variable selection for hydrological predictions Left: EGU 2018 Poster 2—Input variable selection for hydrological predictions in ungauged catchments: with or without clustering? Bottom Centre: YHS team at EGU 2018 (with only a few missing! It is not east to arrange a common time for everyone, even for a group photo)

I also took over the role of EGU ECS Rep for HS division from Shaun Harrigan at EGU 2017. Being elected as the EGU ECS Rep, I became more enthusiastic about advancing the hydrologic science community equally (and globally) in support of, primarily, the ECS. The ECS Rep is expected to contribute to sustainable and inclusive growth of the EGU HS division by fostering the active participation and integration of ECS and the hydrologic science community globally under the umbrella of EGU, keeping in mind the necessity of creating equal opportunities for ECS to enhance their research and communication skills.

EGU ECS Reps at the EGU GA 2018

The ECS Rep for HS division works in close collaboration with YHS to initiate and support inspirational and intelligent ideas in line with the emerging needs of ECS. You also meet with ECS Reps of other EGU divisions and help the EGU community thrive together with its early career members. My term ends in April 2019. So keep your eye on EGU and YHS websites (and twitter) in early 2019—and apply to become the next EGU ECS Representative (April 2019-April 2021) for the HS division!

Do you have any parting words about your time involved with EGU?

It has been a very long post but now here are the last words. The EGU GA means seeing old friends and past professors, meeting fellow hydrologists and listening to presentations from enthusiastic researchers… plus the annual Hydrodrinks event among many other scientific sessions and short courses organized by YHS! I am glad to serve as the EGU ECS Rep for the Hydrological Sciences division – for the wonderful and inspiring people of the red floor:)

Acknowledgements: I would like to express my sincere thanks to Young Hydrologic Society, especially to Wouter Berghuijs, Shaun Harrigan, Hannes Müller and Tim van Emmerik, for their enthusiasm and support over the last five years.

Interview by Olivia Trani, EGU Communications Officer

 

Imaggeo on Mondays: Cumulonimbus, king of clouds

Imaggeo on Mondays: Cumulonimbus, king of clouds

This wonderful mature thunderstorm cell was observed near the German Aerospace Center (DLR) Oberpfaffenhofen. A distinct anvil can be seen in the background meanwhile a new storm cell is growing in the foreground of the cumulonimbus structure. Mature storm cells like this are common in Southern Germany during the summer season. Strong heat, enough moisture, and a labile stratification of the atmosphere enables the development of this exciting weather phenomenon.

Description by Martin Köhler, 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/.