10 Reasons Why …. 10 Rheswm Pam …. : 3

Thursday 28th May 2015

Blog post 3 of 10 about the geomorphology of Wales. Click on images to view larger versions in separate windows. Parallel blog in Welsh at http://hywelgriffiths.blogspot.co.uk/

Reason 3. Landscape processes operate at many different scales. The tectonic, geological, climatic and ecological factors that influence geomorphological processes and movement of mass change with different time and space scales.

Solva overview

Landscapes contain a nested series of landforms of different spatial scale (size), the development of which occurs across a range of temporal scales (time), as illustrated in the area around Solva, Pembrokeshire. The aerial photograph provides an overview of the landscape, showing how low relief, upland surfaces (marked by fields) are dissected by a deep estuarine valley, and end abruptly at a rugged coastline characterised by bays, headlands and offshore islands. At low tide, sand and gravel is widely exposed along the estuary and in pocket beaches (Source: imagery from Google Earth; the image is about 1.5 km across and oriented with south towards the top). The arrows indicate the directions in which the ground-level photographs shown below were taken.

Solva landforms

Ground-level photographs illustrating a range of landforms at different scales: top left) the largest scale landforms such as the upland surfaces and valley have developed over very long timescales (many hundreds of thousands to tens of millions of years) as a result of weathering and erosion. During extended intervals of extreme cold in the past, glacial ice and/or large volumes of glacial meltwater likely occupied the valley many times, contributing to punctuated episodes of more rapid deepening and widening; top right) other large scale landforms such as bays, headlands and islands also have developed over relatively long timescales (likely hundreds of thousands to a few million years) as result of weathering, mass failure (e.g. landslides, rockfall) and wave action. At present, wave action is a potent agent of erosion, especially during extreme storm events, but would have been reduced in importance during the extended colder intervals in the past, owing to global falls in sea level. During the last glacial maximum about 20 thousand years ago, sea levels were about 120 m lower and the shoreline would have been located farther south, far from the mouth of the present-day estuary; bottom left) medium-scale landforms such as gravel beach ridges develop over intermediate timescales (years to decades) in response to high-energy wave events, especially those generated during extreme storm events. Major reworking of the gravel ridge occurs when overtopping waves alter the height of the crest and perhaps cause the ridge to migrate a short distance inland. Occasional floods along the river help to maintain a breach in the gravel barrier, and rework some of the gravel seaward; bottom right) small-scale landforms such as sand ripples develop over short timescales (minutes to hours) in response to the vagaries of river and tidal currents. Such landforms form and reform repeatedly, although never replicate exactly the same patterns of crests and troughs (Photos: Stephen Tooth).

Did You Know?  One of Wales’s most dynamic landscapes is the estuary of the River Severn. The tidal range in the estuary is the second largest in the world, being as much as 50 feet (approximately 15 m). Tides are funnelled from the Bristol Channel into the estuary, which narrows and shallows rapidly upvalley, commonly creating a large (up to 3 m high) surge wave known as the Severn Bore. The bore normally takes 2 to 2.5 hours to travel around 34 km upvalley to Gloucester. River flows combine with the daily tide and wave action to move large volumes of sediment into, around and through the estuary, and give rise to a range of dynamic landforms over multiple scales, ranging from mud ripples to rock cliffs. Although difficult to quantify precisely, it is estimated that the Severn and its tributaries supply about 1 million tonnes per year of sediment to the estuary, with erosion of intertidal mudflats and rock cliffs possibly supplying another 2.5 and 1.3 million tonnes per year, respectively. This annual total of up to 4.8 million tonnes of sediment is about 160 times the weight of reinforcing steel in the Second Severn Crossing, the M4 motorway bridge that roughly marks the lower limit of the river and the head of the estuary. (Sources: The Severn Bore: a Natural Wonder of the World; Detailed history of the M4 Second Severn Crossing; Severn Estuary Shoreline Management Plan Review: Appendix C).

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Frack to the Future?

Sunday 3rd May 2015

In an energy-hungry world, ‘extreme energy’ has been defined as “the process whereby energy extraction methods grow more intense over time, as easier to extract resources are depleted” (see http://extremeenergy.org/2013/07/25/defining-extreme-energy-a-process-not-a-category/). Such methods include mountain top removal for coal, open cast mining for tar sands, hydraulic fracturing for shale gas, and deep water drilling for oil, and their wider deployment across the globe is proving to be highly contentious. And depending on perspective, the method of hydraulic fracturing – commonly shortened to ‘fracking’ – is turning out either to be the bête noir or the poster child of our growing energy crisis. In essence, fracking involves drilling vertically and horizontally into shale rocks at depth and then pumping a mixture of water, sand and chemicals at high pressure to fracture the rocks, enabling any trapped gases to flow into the borehole and then to the surface (http://www.bbc.co.uk/news/uk-14432401). Over the last couple of decades, widespread fracking has enabled the USA to become one of the world’s leading gas producers, and large shale gas resources are known to exist globally, including in Canada, Argentina, China, and Western Europe. Potential shale gas resources are thought to underlie many parts of the UK, which raises the possibility of fracking operations becoming part of our energy landscape, sitting alongside coal-fired power stations, nuclear power stations, HEP reservoirs, and wind farms. Opponents of fracking fear the potential litany of local environmental impacts that may result, including ground and surface water pollution, soil contamination, induced seismicity, and noise. They also point out that shale gas is a fossil fuel, the exploitation of which will simply add to the seemingly inexorable rise of global atmospheric CO2 concentrations and so contribute further to regional and global climate change. Proponents see fracking as an important way to develop a more balanced energy portfolio that reduces dependence on foreign energy imports. They also argue that shale gas may serve as a ‘transition fuel’, gradually substituting for ‘dirtier’ forms of energy production (e.g. coal burning) and so may form one of the stepping stones necessary for attempts to de-carbonise our economy.

While the debate over fracking is commonly caricatured as being played out by two opposing lobbies – the vociferously anti ‘frackivists’ and the rabidly pro ‘hydrocarbon barons’ – the reality is not quite so binary. Many people (including myself) are genuinely interested in the middle ground and the vexing but key questions that lie therein. Can fracking be managed sustainably (economically, socially, environmentally)? Will fracking be a boon or a burden for ailing rural economies? Can fracking improve energy security and be part of a balanced energy supply? Without posing such questions and getting a firm handle on any available facts and figures, meaningful debate can’t take place.

A potential opportunity to examine these and other questions was provided by the public forum entitled “Fracking and the Imagination: Scraping the Barrel or Saving the Day?” that took place at Aberystwyth University Arts Centre on 23rd April 2015. I had a minor role in the organisation of the meeting, which was intended as a transdisciplinary forum that would bring together natural and social scientists, artists and environmental activists from across Wales and beyond. Such variety is essential, for fracking is a complex, multi-dimensional issue that can be examined from many different perspectives. At an early stage, I could see the possibility of the forum serving as a prism for splitting and dispersing the fracking issue into its constituent parts (‘wavelengths’), so enabling informed debate.

fracking tweet 1

My presentation opened the forum by briefly raising many of the above issues, while attempting to focus on the geological context, technologies and possible climatic and wider environmental consequences of fracking.

fracking tweet 2a

As a particular contribution to the ‘imagination’ theme, I tried to look forward in time and ponder the legacy that fracking might leave in the long-term geological record. Would a forensic geological examination of the future Earth reveal signs of the deep physical disturbances associated with fracking, alongside other forms of hydrocarbon extraction, mineral mining, groundwater exploitation and underground construction? Will fracking ‘scars’ be our enduring ‘trace fossils’, cutting across multiple geological strata to mark a putative Anthropocene time interval, in which human activities dominate over nature and influence the geological record? Do we care about this? Should we care about this?

fracking tweet 2b

How successful was the day? You can judge for yourselves by watching some of the presentations online:

http://abercast.aber.ac.uk/Panopto/Pages/Viewer.aspx?id=8cccef00-fed0-4721-a5e8-a279961b99fa

and

http://abercast.aber.ac.uk/Panopto/Pages/Viewer.aspx?id=21bcdb2a-6d54-48d9-8c12-232de167ab74

Some of the tweets from the day have been ‘storified’ (https://storify.com/Samsaville/getting-started), cherry-picked examples of which are embedded in this blog, and the twitter feed is ongoing (#imaginefracking). Other contributors to the forum will be posting their own blogs on the event, and these will provide additional retrospectives (e.g. http://kelvinmason.weebly.com/blog and https://anthropocenedotcom.wordpress.com/).

I thought that the event was very successful: the open forum worked well as a means of debating vexing issues from a variety of perspectives in a non-confrontational atmosphere. Geological, environmental and social perspectives were all covered, including from academic, artistic, activist and political angles. Personally, I would have liked to have heard more about the economic arguments for fracking: other than from one audience member who played devil’s advocate by raising these arguments, this perspective was effectively absent from the forum. Can shale gas really help to reduce energy bills? Can fracking developments lead to long-term jobs creation? Can shale gas really act as a transition fuel? Such questions were left largely untouched.

As someone primarily interested in physical geography and geomorphology, the fracking theme clearly sits some distance outside my comfort zone, and preparing a balanced ‘scene setting’ opening talk had proved more of a challenge than anticipated. Afterwards, I was told that someone had described my talk as ‘factually correct and dispassionate’, so that’s a result as far as I am concerned. Or is it? On such important issues, should scientists like myself always be dispassionate, remaining rigidly impartial and free from personal feeling or emotion?

To retain credibility as a scientist and university educator, the answer is probably ‘yes’. But as a citizen interested in the evolving state of the world, perhaps the answer is ‘no’. For sure, one should stick to known facts and figures, but when these run out – and in the case of debates over fracking, this position seems to be reached quite quickly – surely one has the right to venture opinions and offer value judgements that may be influenced more by gut feeling and perhaps even raw emotion?

Balancing dispassion and passion is like walking a tightrope, but this is a tightrope that increasing numbers of scientists are being forced to tread. The climate change debate – of which fracking forms a part – is a prime example. Over the last 10-15 years, many climate scientists have become increasingly vocal in raising awareness of the environmental and societal consequences of climate change. Some have even eschewed their data crunching safety net to become strong advocates for drastic actions to reduce our fossil fuel addiction, and in the process have found themselves embroiled in fierce media and political battles with climate change denialists, sceptics, politicians and big business interests. Jim Hansen (http://www.theguardian.com/environment/2009/jan/18/obama-climate-change), Michael Mann (http://www.theguardian.com/environment/video/2012/feb/17/climate-scientist-michael-mann?intcmp=239) and the late Stephen Schneider (http://climatechange.net/) are just three names that spring to mind. Any stumble on the tightrope can be injurious to one’s career and reputation. But surely some scientists have to engage in such activities, if only to bring some counterbalance in debates that would otherwise be populated with less-informed participants and ‘business as usual’ advocates.

fracking tweet 3

The nice thing about the “Fracking and the Imagination” forum was that there was the opportunity to show both dispassionate and passionate faces. My presentation tried to show the former, but by taking part in the afternoon panel discussion, I found myself venturing those opinions and value judgements. Is fracking akin to scraping the barrel or will it save the day? Despite the virtual absence of the economic arguments, it does seem that fracking and other extreme energies reflect extreme desperation: ‘sprinting in the wrong direction’ to quote another panellist (Damien Short). The amount of energy that needs to go into extracting the energy from unconventional resources reflects diminishing returns, and just like conventional gas, coal and oil, surely fracking and similar developments can only have a finite lifetime (a few decades)? Shouldn’t society reverse, turn 180 degrees and sprint the other way, throwing more efforts towards developing renewable energy resources? If we can put people on the Moon, control rovers on Mars, and land instruments on comets more than 6 billion kilometres miles away, surely we can improve the scales and efficiencies with which we extract energy from the Earth’s internal heat and its sunshine, wind, waves and tides? Of course, such renewables may also have environmental impacts. But my hunch is that the impacts will be far less widespread and far less enduring than a full rollout of fracking operations across the globe.

Against this backdrop, what should we make of Ceredigion County Council’s decision to become the first ‘frack free’ local authority in Wales? The vote on the motion (28th January 2015) wasn’t unanimous (13 for, 9 against, 15 abstentions). Regardless of the numbers, given that Ceredigion has no viable resources of shale gas (or indeed coal bed methane or shale oil), is this a meaningless gesture or symbolically important? The motion made clear that, if adopted, it would demonstrate the Council’s commitment to a cleaner energy future and set an example for the rest of Wales. And on a broader, global front, there are calls to go even further and pressurise companies and institutions to divest from oil, coal and gas companies, as exemplified most prominently by a group of Stanford University Professors (http://www.theguardian.com/environment/2015/jan/11/stanford-professors-fossil-fuel-investments). The outgoing editor of The Guardian newspaper has urged more scientists to ‘speak up’ on such fossil-fuel divestment (http://www.nature.com/news/scientists-must-speak-up-on-fossil-fuel-divestment-1.17325?WT.ec_id=NEWS-20150416). It remains to be seen just how many will be willing to walk that part of the tightrope.

While I was finishing this blog, it struck me that opposition to environmental developments – be it for energy or something else – is often characterised as NIMBYism (Not In My Backyard-ism). But in the case of Ceredigion County Council, as well as supporters of fossil-fuel divestment, surely it’s NIABYism (Not In Anyone’s Backyard-ism). It’s a horrible acronym. But my feeling is that this is the least of our concerns if the UK and other countries really do roll out large-scale fracking operations and we don’t wean ourselves off fossil fuels, conventional or unconventional.

So, frack to the future? Do we really understand all the potential environmental consequences of fracking? Is it really possible to know the legacy that fracking might leave in the long-term geological record? In both cases, the truthful answer is ‘probably not’. But just as we attempt to deal with the environmental hazards left by Victorian era lead, zinc, copper and coal mining – many of much surely could not have been foreseen at the time – will future generations have to grapple with the hazards of fracked landscapes and a CO2-enriched climate? Will those generations wish that they could jump into Doc Brown’s modified DeLorean and race back in time to intervene in our current energy policy decisions, so changing the course of future events?