GM
Geomorphology

Report

Stormy Geomorphology

Stormy Geomorphology

 – written by James Tempest (University of Cambridge), Larissa A. Naylor (University of Glasgow), Tom Spencer and Iris Möller (University of Cambridge) –

Extreme storm and flood events are occurring with increasing frequency and intensity across the globe causing significant geomorphic change throughout many landscapes often with detrimental impacts on local populations.

Boat washed onto shore following major storm surge in N. Norfolk, U.K. (credits: James Tempest)

In 2014 an international meeting hosted by the Royal Geographical Society and British Society for Geomorphology brought together world-leading experts in this field to showcase the fundamental role geomorphology plays in the age of extremes. The outcomes of the meeting were published in a special issue of Earth Surface Processes and Landforms which included a State of Science paper on this topic (see below). These papers highlighted how geomorphic contributions can enhance our ability to predict, measure and manage the landscape to be more resilient to effects of extreme events.

Predicting extreme hydrological events are an important area of research but such forecasts are often limited by the short length of current river flow records which only extend to the mid 20th Century. Palaeogeomorphology studies resolve such issues by reconstructing historical flood events thereby extending the flood record further back in time to capture these extreme events. Such records not only improve the forecasting of extreme events by providing models with much needed additional data but also allow us to interpret the interactions between geomorphic dynamics, human impacts and changes in climate regimes.

Extreme events witnessed over recent years have raised awareness of policy-makers and practitioners about the important role that geomorphology can play in both managing the landscape and human impacts to these extreme events. Geomorphic processes can both mediate and increase the geomorphological impacts of extreme events, influencing societal risk. This includes determining the resilience and recovery of landscapes, such as barrier islands, to extreme events that may offer some form of natural flood defence. In addition, geomorphological science is now regularly used to deliver nature-based management approaches, such as the creation of coastal wetlands. Such approaches are delivering more sustainable forms of flood and storm defence that are effective in reducing damage and destruction brought about by extreme events.

Sea-defence repair and re-distribution of sediments at Chesil Beach, U.K. following 2014 storms (credits: James Tempest)

Geomorphological science is undoubtedly improving our understanding of flood risk through extreme events yet it is still under-appreciated and under-utilised by the engineering community and policy-makers. Future climate change adaptation and disaster risk reduction strategies must consider geomorphology as an important component in determining and managing the response of landscapes in order to protect human assets in an age of extreme flood and storm events.

http://onlinelibrary.wiley.com/wol1/doi/10.1002/esp.4065/abstract

http://onlinelibrary.wiley.com/doi/10.1002/esp.4062/abstract

 

 – written by James Tempest (University of Cambridge), Larissa A. Naylor (University of Glasgow), Tom Spencer and Iris Möller (University of Cambridge) –

Report from the Summer School on Geomorphology in the Kaunertal Valley, Austria, 31st August – 6th September 2015

Written by Ciara Fleming ( University College Dublin)


The focus of this Summer School was ‘Sediment dynamics in high mountain environments’ and as suggested by this title, the location did not disappoint. For the week-long school we were based in Feichten im Kaunertal (1273m a.s.l.), a perfectly-formed Alpine village in the Province of Tyrol, Austria. The school brought together a diverse group of geoscientists, from Europe and further afield as far away as South America, South Africa and New Zealand. Organised by a group of early career scientists based in Germany and Austria, the rationale behind the school was to combine various disciplines including geology, geochemistry, biology and environmental sciences, and educate postgraduates both in a field site setting and in subsequent workshops. Enabled by the Volkswagen Stiftung Foundation, the costs of the school were fully-funded, and as participants, we were looked after extremely well.

Feichten im Kaunertal, Tyrol, Austria (Image credit: Ciara Fleming).

Feichten im Kaunertal, Tyrol, Austria (Image credit: Ciara Fleming).

After some comprehensive introductory keynote lectures on the first day, we were led on a hike through the Kaunertal Valley from the Subalpine zone to the Alpine, right up to the toe of Gepatschferner, the second largest glacier in Austria, and then subsequently descended down the valley alongside the River Fagge. The scenery was such that for those of us on their first trip to the Alps, numerous pit-stops were made to take it all in, examine the landscape, talk to other participants, take some photos and of course, take a breath! The benefits of fieldwork – making your own observations, grounding concepts and theories learned in the classroom, teamwork skills and many more – were highlighted in this short reconnaissance trip.

Trail leading to Gepatschferner (in the distance), along the 1850 lateral moraine surface (Image credit: Ciara Fleming).

Trail leading to Gepatschferner (in the distance), along the 1850 lateral moraine surface (Image credit: Ciara Fleming).

Over subsequent days, methods in geomorphology came to the fore. This was an excellent chance to learn about the various tools available for us to use as geomorphologists, and examine the limitations of the various methods of data acquisition. To image the sub-surface, two geophysical methods were employed – ground penetrating radar (GPR) and electrical resistivity tomography (ERT). More traditional methods of investigating geomorphological parameters included water/sediment discharge measurements and biogeomorphological vegetation/sediment sampling. Extremely high resolution digital elevation models were created using the latest equipment including a terrestrial laser scanner (TLS) and unmanned aerial vehicle (UAV). The rain descended over the hilltops on one of these days, but didn’t dampen our spirits. To my surprise, many of the participants were ready with umbrellas – being trained as a field geologist in Ireland, there is no need for an umbrella as the rain tends to sheet horizontally, rendering an umbrella rather ineffective! One of these field days ended with a quick stop at the Gepatsch Stausee (reservoir), where the Kaunertal power station harnesses energy from the glacial rivers and streams of the surrounding valleys.

Summer school participants conducting ground penetrating radar, adjacent to the River Fagge braidplain (Image credit: Ciara Fleming).

Summer school participants conducting ground penetrating radar, adjacent to the River Fagge braidplain (Image credit: Ciara Fleming).

Measuring turbidity in the water column of the Riffler Creek, a tributary of the River Fagge (Image credit: Ciara Fleming).

Measuring turbidity in the water column of the Riffler Creek, a tributary of the River Fagge (Image credit: Ciara Fleming).

 

The braidplain of the River Fagge in the foreground, with Gepatsch Stausee in the background (Image credit: Ciara Fleming).

The braidplain of the River Fagge in the foreground, with Gepatsch Stausee in the background (Image credit: Ciara Fleming).

These experiences in the field were bookended by workshops during which we processed the collected data, using various bespoke and open-source software packages. Various issues regarding real-world datasets were highlighted during these discussions, including interpretation of measurements, troubleshooting incomplete datasets, combining multiple analytical techniques among many others. These lessons are vital to us postgraduate researchers, as we will need to consider such practicalities and limitations when collecting and analysing our own field data.

On the Thursday evening, following a long day of data processing and fieldwork, we were given tips on reviewing and authoring by the editor of Earth Surface Processes & Landforms. Despite the late hour, Professor Stuart Lane was a captivating speaker, and managed to maintain the attention of his audience throughout. This was followed in the morning by an extensive talk on sediment budgets. On Friday night we were treated to some traditional Austrian hospitality and panoramic views (1962m a.s.l.) at Falkaunsalm, an Alpine hut outside Feichten. A veritable feast of Austrian fare was provided including various meats, sauerkraut and dumplings, followed by a traditional pancake dessert called Kaiserschmarrn. Many of the participants followed up with a digéstif of pine-flavoured schnapps, an overwhelming smell – it was almost like drinking a Christmas tree!

Sunset view over the Alps from Falkaunsalm, an Alpine hut outside Feichten (Image credit: Ciara Fleming).

Sunset view over the Alps from Falkaunsalm, an Alpine hut outside Feichten (Image credit: Ciara Fleming).

The penultimate day consisted of the final data processing workshop followed by lectures and discussions on risk assessment and how society interacts with hazards in Alpine settings. The social evening was a welcome opportunity to relax after a busy week, and for those of us who stayed up into the wee hours, to hear some renditions of Austrian classics! Recuperating from heavy heads in the morning was eased somewhat by an excellent speaker Professor James Kirchner, discussing a very meaty topic, statistical analysis of environmental data. Before departing, a plenary session was held with the organisers to evaluate the summer school, and we all agreed it was an inspiring and scintillating experience which was efficiently organised. For me, this was a week of firsts – my first time in Germany, my first time in Austria, my first time in the Alps and I know one thing for sure – I’ll be going back!

Written by Ciara Fleming ( University College Dublin)

Joint MSc field course in geomorphology (Universities of Bonn and Salzburg)

Joint MSc field course in geomorphology (Universities of Bonn and Salzburg)

From Wednesday to Saturday 9-12 September 2015, the geography departments of the Universities of Bonn/Germany and Salzburg/Austria, held a joint field course in geomorphology in the eastern European Alps. During these four days, 24 students master students, half from each participating university, gathered in Gmunden, Austria. Here, in the beautiful Salzkammergut, the course addressed topics of geomorphology, geoarchaeology and natural hazards. During field trips and hands-on workshops, the students conceptualized and conducted traditional drilling techniques, geophysical surveys and terrestrial laserscanning to investigate surface and subsurface characteristics in several key sites.

In the Gschliefgraben, a complex and currently reactivating landslide at the northern foot of Mt. Traunstein, the depth of the failure plane and the subsurface moisture distribution was investigated using electrical resistivity tomography. Within a nearby Weichselian sandur plain the students sought to determine the extent of the so-called Roman Villa Engelhof using ground-penetrating radar.

Wenner_129m_P2The shape and infill of a nearby located kettle hole mire (Krottensee) was investigated using electrical resistivity tomography. The figure below shows one of the resulting tomographies clearly indicating three layers with a floating mat on top in red, a body of water/gyttija underneath in blue, and the morainic kettle hole base in green colours.

P1080822Recent rockfall activity at the south face of Mt. Plassen (see picture to the left, nearby Hallstatt) and the north face of Mt. Traunstein was finally investigated and quantified by means of terrestrial laserscanning.

The field course was hosted by five lecturers from the Universities of Bonn and Salzburg, Dr. Johannes Weidinger, Prof. Lothar Schrott, Dr. Joachim Götz, Dr. Thomas Hoffmann and Dr. Jan Blöthe. This was the first joint field course between two European Universities that we organized and even though the courses in both departments had a slightly different focus, bringing these ideas together in the field was easy. We have the feeling that students from both universities benefited from the discussions and the exchange of thoughts during field work. After this very positive experience, it probably won’t be the last joint MSc course we organized.

– Written by Jan Blöthe (University of Bonn, Germany) and Joachim Götz (University of Salzburg, Austria);
Featured image courtesy of Christoph Baumgartner

Global Soil and Sediment Transfers in the Anthropocene (GloSS) – Report from the kickoff meeting in Bonn

pages_glossOpen kickoff meeting of the PAGES working group held in Bonn, Germany, 19th – 21st Aug. 2015

The open kickoff meeting of the PAGES working group GloSS aimed to set the boundary conditions that will enable the GloSS-WG to meet its scientific goals within the next three years. Therefore, this workshop focused on the development of a list of proxies/indices of human impacts on soils and sediments that will support the compilation of a global soil and sediment database. A total of 30 participants from different disciplines (geomorphology, geology, soil science, ecology, (palaeo)limnology, hydrology and geoarchaeology) and seven countries and four continents contributed to the workshop.

The first 1 ½ day were dedicated to continental reviews of proxies of human impacts on soils and sediment transfers. The keynotes were given by Gary Stinchcomb (Murray State University), Tim Beach (University of Texas at Austin), Juan Restrepo (EAFIT University of Medellin), Dan Penny (University of Sydney), Hongming He (Chinese Academy of Science), Lishan Ran (National University of Singapore), Rajiv Sinha (Indian Institute of Technology, Kanpur) and Gert Verstreaten (Leuven University). The regional reviews were complemented by a keynote of Jane Willenbring (University of Pennsylvania) on a global view on sediment production and export and a contribution via skype Nicholas McKay (Northern Arizona University) on his experiences building the PAGES 2k database.

During the second and the third day the workshop participants i) developed a concept that organizes proxies of human impact on soil and sediment dynamics for hillslopes, floodplains, lakes and deltas covering different time scales during the Holocene, ii) discussed potential stakeholder, and requirements of a GloSS-database, and iii) discussed its structure and developed a road map for the first three years.

The participants of the breakout discussion group on human proxies agreed that the primary GloSS-data sets should be proxies/indices that focus on soil erosion and sediment transport and deposition and do not include other proxies (such as pollen or diatoms). While volumetric and/or mass balance proxies are generally favoured compared to length per time proxies (such as sedimentation and/or erosion rates given in mm/a), it was noted that length-based rates are an invaluable tool for constructing such sediment budgets and that for many study sites complete quantitative inventories are not available and difficult to obtain. Thus length-based rates were considered as very valuable information that should be considered but interpreted with great care. Regarding the considered timescale, a conservative estimate of the Holocene was decided to be the operational time frame for the GloSS datasets, allowing  estimation of natural base line conditions.

The discussion on the database content and structure resulted in the following statements: The GloSS-DB should focus on soil erosion, sediment transport and deposition of the following environments: hillslopes, floodplains/channels, lakes and deltas. There is no need to populate the GloSS-DB with other available paleo-environmental information. Instead, the GloSS-DB should be linked to other existing databases (esp. developed within the PAGES-Community) to avoid redundancy where possible.

The group agreed that human impact on the above-mentioned environments is best described by the change of erosion, transport and/or deposition. Thus, at minimum two ‘time slices’, before and after human impact, for the three variables are necessary. Due to the major challenges to define what human impact actually is and when it starts in different regions of the earth, it was argued that the number of time-slices should be maximize to allow flexible interpretations without constraining what the user can interpret from changes (e.g. climate versus human impacts).

To set the boundary conditions for the first three years of the GloSS working group, a roadmap, seven regional task forces and a database task force was build. The regional task forces and their leaders are:  i) Europe and Mediterranean (Gert Verstraeten), South Asia (Rajiv Sinha), Australia / NZ (Bob Wasson, Duncan Cook),            East and Central Asia (Hongming He, Lu Xixi), North-America (Jane Willenbring, Gary Stinchcomb), South and Central America (Juan Restrepo), Africa (Klaus Martin Moldenhauer, not fixed at this time). The database task force has following members: Jane Willenbring, Gary Stinchcomb, Veerle Vanacker, Dan Penny, Lishan Ran, Jean Philippe Jenny, Nick Mackay, Kim Cohen and Thomas Hoffmann.

– Written by Thomas Hoffmann, University of Bonn

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