Energy, Resources and the Environment

Words on Wednesday: Developing a functional model for cities impacted by a natural hazard: application to a city affected by flooding

ERE Matters March 31, 2015

Words on Wednesday aims at promoting interesting/fun/exciting publications on topics related to Energy, Resources and the Environment. If you would like to be featured on WoW, please send us a link of the paper, or your own post, at ERE.Matters@gmail.com.

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Bambara, G., Peyras, L., Felix, H., and Serre, D. (2015), Developing a functional model for cities impacted by a natural hazard: application to a city affected by flooding, Nat. Hazards Earth Syst. Sci., 15, 603-615, doi:10.5194/nhess-15-603-2015

Abstract:

The experience feedback on a crisis that hit a city is frequently used as a “recollection” tool. To capitalize information about an experience feedback from the cities that have been affected by a natural hazard, the authors propose in this study a functional model to model scenarios of city crises. In this model, the city, considered as a complex system, was modelled using a functional analysis method. Based on such modelling, two risk analysis methods (Failure Mode and Effect Analysis and Event Tree Method) were deployed and adjusted. Lastly, a qualitative reasoning model was used for the scenario modelling of the urban crisis. By functional modelling performed on components of the cities, the objective of this model is to replicate the behaviour of a city affected by a crisis, highlighting the sequences of failure and non-failure modes that have operated during the crisis. This model constitutes a means of understanding the functional behaviour in a crisis of cities and capitalization of the experience feedback of the cities affected by crisis. Such functional modelling was deployed in a case study.

I’m a Geoscientist: Sian Loveless – ‘Young Scientist Representative’ Officer

ERE Matters March 20, 2015

It’s I’m a Geoscientist week! Or more exactly: weeks. From March 9 until March 20, the EGU supports I’m a Geoscientist to help students engage with scientists about real science. The Energy, Resources and Environment Division of the European Geosciences Union encompasses a broad range of different ERE-related topics, from surface to subsurface, spanning all aspects of geosciences. In order to demonstrate how broad the Division actually is, and what you can do as a geoscientist to be involved with energy, resources or the environment, we asked the members of the ERE committee to introduce themselves and explain how their day-to-day work relates back to ERE.

We will end our trip past the members of the ERE committee with our Young Scientist Representative Sian Loveless. She mainly works on bringing together ERE and you (yes, you my dear YSs!).

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At my first EGU GA (General Assembly) in 2011 I took the opportunity to visit a number of Energy Resources and Environment (ERE) sessions, though they were not directly related to my PhD research. Topics within the Division of ERE tend to be of interest to academics, industry, policy-makers and the wider community as they have clear societal impacts and are therefore often rather accessible. In addition, shifts in ERE “hot topics” can occur year to year as contributors respond to evolutions in society. As an example, at the 2011 GA two presentations concerned Shale Gas; three years on, in 2014, the terminology evolved to Unconventional Hydrocarbons (to include other novel resources) and there were now a number of popular dedicated sessions.

It was the relevance of the ERE talks that attracted my attention, in particular those presenting case studies in the more novel fields of CCS (Carbon, Capture and Storage) and Geothermal Energy. Suitably impressed by these I moved to Belgium to work in Research and Development of Geothermal Energy for a technology research institute. I recommend a visit to ERE sessions to other curious researchers from across the EGU Divisions and in particular Young Scientists seeking pathways for their research.

I now spend part of my time on “strategic” or more fundamental research and part on defined geothermal feasibility and development projects. This can be a peculiar locus; trying to marry-up sophisticated in-depth research with practical challenges. A major challenge in Geothermal Energy assessment is identifying the nature of geological fault zones. Faults (and associated fractures) can be very permeable to fluids (conduits) and thus a prime target for geothermal energy, or conversely very impermeable (barriers) and should be avoided. Faults thus have significant impacts on the viability of a geothermal project. There is a marked disparity between the scale at which this problem is and can be considered. Fault permeability depends on a wide range of parameters and may vary between the two extremes even along the same fault. Rightly, much academic research is devoted to understanding these intricacies. However there is generally limited data available at depth which requires that generalisations and assumptions must be made about the nature of the fault permeability to allow progress. I see ERE sessions at the EGU GA as a tool to bring together industry and academics to present and discuss these different perspectives.

Fault in Central Greece showing highly permeability down-thrown gravel beds in the hangingwall juxtaposed against low permeability marl beds in the footwall. Juxtaposition of sediment/rock with different hydraulic properties is one of the main ways in which faults can impact subsurface fluid flow.

Another potential function of ERE sessions is to be a platform for two-way interaction with policy-makers. Policy decisions have a critical impact on the realisation of Geothermal Energy and other green/sustainable technologies, remaining a major barrier to its adoption in many countries. As a first step we have introduced the session “ERE in Policy” to the 2015 programme in which we hope that knowledge in policy theory and practice can be efficiently and openly shared across industry, academia, research institutes, across country borders and disciplines.

As the Young Scientist Representative of the ERE Division I am interested in promoting involvement for all Young Scientists so please contact me (sian.loveless@gmail.com) with any feedback. In particular please consider submitting a blog-post related to ERE – topics can be varied, from your own research to news articles and interesting conferences that you have attended – we’d love to hear from you!

I’m a Geoscientist: Suzanne Hangx – ‘Subsurface’ Officer

ERE Matters March 16, 2015

It’s I’m a Geoscientist week! Or more exactly: weeks. From March 9 until March 20, the EGU supports I’m a Geoscientist to help students engage with scientists about real science. The Energy, Resources and Environment Division of the European Geosciences Union encompasses a broad range of different ERE-related topics, from surface to subsurface, spanning all aspects of geosciences. In order to demonstrate how broad the Division actually is, and what you can do as a geoscientist to be involved with energy, resources or the environment, we asked the members of the ERE committee to introduce themselves and explain how their day-to-day work relates back to ERE.

From above ground, we will dive down below into the subsurface with Suzanne Hangx, post-doctoral researcher at the High Pressure and Temperature Laboratory at Utrecht University.

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In my research, I have always been driven by curiosity about the physical and chemical processes that control rock material behaviour in the subsurface, along with the direct relevance of this field to socially relevant issues. Naturally, working on energy, sustainability and the environment from a geoscientific point of view was a logical step. I want to contribute to solving geo-energy problems, by investigating and quantifying related risks, such as climate change caused by greenhouse gases or surface subsidence caused by oil/gas/ground water production, and contribute to socially acceptable solutions or technologies.

For about 10 years I have mainly been working on CO₂ Capture and Storage (CCS). It is considered to be one possible route to get rid of large quantities of CO₂ by injecting them into the subsurface, reducing its effect on climate change. Suitable locations are depleted oil or gas reservoirs, or aquifers, at several km’s below the surface. However, it is important to ensure that after injection the CO₂ also stays there – not just today or tomorrow, but for thousands of years. Once a potential injection site is suggested, it is important to see if the reservoir (the ‘container’) and the seal keeping the CO₂ in place (the ‘lid’), are up for the job, so to speak. I investigate if the injected CO₂ does anything to the rocks to alter their mechanical behaviour, i.e. how they break, under which force they break and if they get weaker by the presence of the CO₂.

When you inject CO₂ into a depleted oil or gas reservoir, part of it will start to dissolve into the water that is present in that reservoir, while the rest will stay in a dense liquid or supercritical phase. When CO₂ dissolves in water, the water will become acidic. This acidic fluid can chemically interact with the surrounding rocks, and certain minerals may dissolve and new ones may be formed. In addition, the way cracks propagate through the rock may be affected, changing their strength and the way they break. If a rock gets sufficiently weakened by the chemical interaction with CO₂ it may compact or break, which we would like to know in advance!

In Utah, natural CO2 accumulations are present within the Entrada Sandstone (‘Layer Cake’ by Suzanne Hangx, via ImagGeo)

Such chemical interactions may occur on different timescales. Processes that happen in days, weeks or months can still be dealt with in a laboratory setting. However, to be able to predict what will happen on the timescale of thousands of years, we are currently trying to learn as much as we can from naturally occurring CO₂ fields, such as those in Utah (USA), Australia and Europe. These fields can contain over 90% pure CO₂ and have mostly done so for thousands of years. Studying these fields can help us understand better how subsurface storage of anthropogenic CO₂ will evolve over time.

Nowadays I’m trying to apply what I learned during my research on the chemical-mechanical interactions occurring in rocks to understand surface subsidence, and related induced seismicity, resulting from the production of fluids such as oil and gas. Though dealing with a different setting, the mechanisms and processes are similar to those of interest for CCS. Given their interdisciplinary nature, the ERE sessions at the EGU General Assembly are the perfect platform for me to show my most recent research in both areas!

I’m a Geoscientist: Viktor Bruckman – ‘Above Ground’ Officer

ERE Matters March 13, 2015

It’s I’m a Geoscientist week! Or more exactly: weeks. From March 9 until March 20, the EGU supports I’m a Geoscientist to help students engage with scientists about real science. The Energy, Resources and Environment Division of the European Geosciences Union encompasses a broad range of different ERE-related topics, from surface to subsurface, spanning all aspects of geosciences. In order to demonstrate how broad the Division actually is, and what you can do as a geoscientist to be involved with energy, resources or the environment, we asked the members of the ERE committee to introduce themselves and explain how their day-to-day work relates back to ERE.

After a flight through the scientific world of mining, nuclear energy, CO₂ storage and groundwater flow, today we will stay above ground, with our ‘Above Ground’ Officer Viktor Bruckman, who is working at the Austrian Academy of Sciences.

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The European Geosciences Union (EGU) Division on Energy, Resources and the Environment (ERE) deals with some of the most important aspects for sustaining humanity. The current demographic trend of a growing world population with increasing demands of energy and resources defines a challenging task in developing policies for a sustainable future. Such frameworks need to be implemented on a sound scientific basis and the ERE division provides a forum for discussing state-of-the-art projects and results at the annual general assemblies and beyond. At the ERE division, I am responsible for the aboveground section, which includes most of the renewable sources of energy (e.g. wind power, hydropower, solar power) and other resources, such as biomass.

My own background is forestry, with a strong specialization in the areas of carbon cycling and sequestration, as well as the production of biomass. I am working for the Commission for Interdisciplinary Ecological Studies at the Austrian Academy of Sciences (ÖAW) that taught me to approach problems in a holistic and interdisciplinary fashion. And these are the best lessons learned in order to serve the ERE business. Indeed, the provision of sustainable resources are a very interdisciplinary matter, specifically because it is based on interventions on land and consequently causes land use change (LUC), a term recently stressed a number of times, in particular with Climate Change.

This thought alone highlights the complexity of the topic as renewable resources are commonly seen as the potential successors of the fossil sources in order to move our society towards a development based on a solid bioeconomy. In-depth analysis, however, shows that renewables are not per se better than non-renewable sources and in some cases they are even worse. This is true even from an economical point of view, especially when internalizing all associated costs, including e.g. loss of biodiversity etc. Therefore, we need a very sound understanding on how the development of renewable sources of feedstocks and energy impacts the environment and its services, which are delivered at no financial costs to the humanity (so-called ecosystem services).

Over time, biochar particles are fully integrated into the soil system and act as a reservoir for nutrients and water as shown here by intensive occurrence of mycorrhizal hyphae (orange structures). This SEM illustration shows charcoal which was found in a spruce-dominated forest soil in the northern part of Austria and likely origins from the previously common silvicultural practice of slash burning. The age of the charcoal shown here is around 110 years, and it still shows no signs of decomposition, therefore impressively demonstrating its capabilities of securely sequestering carbon. Source: Bruckman, V.J. and Klinglmüller, M. (2014): Potentials to mitigate climate change using biochar – the Austrian perspective. IUFRO Occasional Papers (27) 1-19.

Experts agree that atmospheric CO₂ emitted from anthropogenic sources plays a major role as a greenhouse gas (GHG). Biomass – and this is the point, where I would like to come back to my own research – has some interesting, but very region-specific potentials to reduce emissions or even sequester additional carbon from the atmosphere. An increased substitution of fossil with renewable resources that are produced under sustainable conditions may reduce large amounts of carbon emissions. My research team goes even further and proposed negative carbon emissions when using biomass as source for energy. This can be realized when combining biomass and CCS (carbon capture and storage), by producing biochar, for instance. Biochar is the solid, carbon-rich residue of biomass pyrolysis, the heating of biomass in an oxygen-low environment. The material is closely related to wood charcoal used for barbecue, just with a distinct different function. It is used as a soil amendment and, because of its unique porous structure and chemical composition it may enhances soil fertility while being very resistant against microbial decomposition. The positive effect may be realized as a consequence of increased nutrient- and water retention, improvement of soil structure and higher cation exchange capacities (CEC). Moreover it can serve as a habitat for soil microorganisms as well as soil fungi (mycorrhiza) that is known to support plant growth in a symbiotic relationship.

This example shows that the ERE division is indeed one of the most interdisciplinary divisions with a large number of connections within the EGU. This is also expressed by the large number of co-organized sessions with various other divisions. I personally enjoy working for ERE and thus add a small contribution of ERE’s success for the sake of science and ultimately a sustainable future.