New paper: Soil mineral depletion drives early Holocene lake acidification

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By Richard Chiverrell

Every year, about May, student examination season begins, teaching winds down and the thoughts of Physical Geographers turn to fieldwork, travel, seeing the world, all preferably with sediment corer in hand. In 2007 an intrepid team of John Boyle, Rich Chiverrell, Andy Plater and Oliver Boyle (John’s brother) set sail, more or less literally for Norway, on the Newcastle to Bergen ferry. Our travels were to test a numerical model developed by John Boyle that suggested that changes in lake and terrestrial ecosystems, the acidification of surface waters during the early postglacial period, could be explained by the weathering and depletion of the mineral apatite from soils. The modelling was published in a brilliantly titled paper ‘Loss of apatite caused irreversible early-Holocene lake acidification’ in the journal Holocene. We docked in Bergen around 6pm and then drove for 12 hours to north of Nordfjord to the island of Vågsøy, avoiding reindeer, sleep, horrendous sheeting rain and sadly all the Nordfjord ferries (closed for the night), to sample the sediments of Kråkenes Lake. We arrived around 6am and grabbed 4-5 hours sleep in a delightful sea front cottage, before sampling a 8.96-m-long core from the terrestrialized peat bog that forms the southwestern arm of the lake using a 1-m-long, 70-mmdiameter Russian corer in 10 overlapping drives. The coring was completed in 4 hours, a pretty remarkable 2 days. After surviving on meagre rations of vacuum packed gammon and Uncle Ben’s stir fry sauce (note other brands exist) prompted by the lack of fishing prowess displayed by members of the team (they did catch seaweed) and Sunday shopping hours in Norway (i.e. closed), we had two days to explore the catchment and the seaboard of western Norway on our journey south. Thankfully the shops opened Monday and more fitting food stocks were procured.

Twelve months later we won a Natural Environment Research Council Grant to carry out the first validation of John’s numerical model, principally testing whether the changes in soil primary mineral concentrations after the end of the last Ice Age deplete at the same rate and extent as the acidification observed in many postglacial and formerly glaciated lakes. Easily weathered minerals in this case apatite (source of mineral phosphorus) appear to be quickly released to soils and water courses producing a base-rich phase seen in lake sediment records with an associated higher ecological productivity early after deglaciation, and this phase ends as the supply of base declines. The acidification that follows had previously been attributed to climate change and plant-soil community succession. The findings of this research, with the laboratory work completed by research assistant Dr Ian Thrasher, have just been published in the journal Geology in a paper called ‘Soil mineral depletion drives early Holocene lake acidification’. Hopefully you will be convinced by our case! The explanation in this paper has some wide ranging implications, mainly arising from that this acidification process is difficult to reverse, unless you completely refresh land surfaces e.g. a new glaciation, producing new terrain by volcanic eruption or really really large-scale turn-over of soils by erosion. We will be following these implications up with further papers on phosphorus dynamics and other implications in the coming months.

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Rapid retreat of the Irish Sea Ice Stream – just out in the Journal of Quaternary Science

British-Irish Ice Sheet

The last glacial maximum of the British and Irish Isles

A new paper has just been published by Richard Chiverrell and co-workers presenting the first Bayesian integration and modelling of all the dating control for the marine sectors of the largest ice stream that the last British-Irish Ice Sheet ~ 24,000 years ago. The modelling shows very rapid retreat for this marine-terminating ice stream over greater distances (650 km) and timescales (8000 years) than is available from short term (decadal) observations of present day ice stream margins. Current marine-terminating ice streams (e.g. Pine Island, West Antarctica) are also known to fluctuate rapidly, with significant concerns over the future rate of ice marginal retreat. Our modelling shows this retreat 24,000 years ago was rapid and linked with climatic warming, sea-level rise, mega-tidal amplitudes and reactivation of meridional circulation in the North Atlantic. But, significantly the pattern of retreat appears uneven with a pulsed pattern of retreat attributed to the passage of the ice stream between normal (sloping away from the ice margin) and adverse (sloping towards) ice bed gradients and changes in the geometry or marginal constriction of the ice stream.

So far no dataset for a retreating ice stream margin has been available to test patterns and rates of change over these millennial timescales relevant to significant distances of retreat >100 km. These data demonstrate the importance of the ice-bed slope and lateral extent for predicting ice marginal behaviour during phases of rapid collapse, and this has importance for present-day ice streams. Understanding of the behaviour of marine terminating ice streams during periods of rapid retreat is based on typically 30 years of monitoring data; the paper shows how ice stream geometry is critical over much longer timescales and for greater distances of retreat. The data reported potentially form validation material for ice sheet computer models that attempt to simulate the decline/collapse of marine terminating ice streams. To read more click here.

The methodology and application was an important test case for Britice-Chrono, a Natural Environment Research Council funded Consortium that over the next five years aims to constrain rates of and controls on marine ice stream retreat over millennial timescales for eight ice stream radiating out from the last British-Irish Ice Sheet. The methodology outlined in the paper will underpin and be used as a guide for our data collection for the wider British-Irish Ice Sheet.

For news and updates on Britice-Chrono see our Twitter site.

Exciting New ESRC North West Doctoral Training Centre CASE Award in the Geography

NewPaperBlog

By Karyn Morrissey

‘Quantifying the Economic Value of the Data obtained from Gauging Stations in Scotland: A Users Perspective’ This ESRC CASE award, http://www.nwdtc.ac.uk/, is an exciting inter-disciplinary studentship that will use non-market valuation techniques to value the river gauging system in Scotland. The student will work with supervisors in the University of Liverpool, Department of Geography and Planning (Dr. Karyn Morrissey and Dr. Neil MacDonald) and a supervisor in the Scottish Environment Agency to extend current valuation methodologies to the valuation of the river gauging system in Scotland.

The Scottish Environment Protection Agency (SEPA) monitors river water level and quality at 392 gauging stations throughout Scotland. Data on river flow and water quality is used by a diverse range of interest groups, including industry, water authorities, wildlife and water managers, hydrologists, recreational and industrial fishers among others; but most importantly Category 1 Emergency Responders and local populations are reliant on the data produced by the gauging stations to provide flood warnings. Data from gauging stations inform the management of water resources to help meet Water Framework Directive Objectives, the design of new infrastructure on and across flood plains, and have been increasingly used by scientists and policy practitioners to evaluate the impact of changes in land use and climate change. The data obtained from river gauging stations are thus a public good and accrue benefits above their market value, but to date no evaluation of the economic benefit has been made. The aim of this project is to examine the value of the data provided by river gauging stations in Scotland, using non-market valuation techniques, specifically choice experiments (CE).

For any student that is interested in apply for this exciting studentship; the criteria are as follows:

Students need to have a good degree (first class or upper second) in Geography (physical and/or human), Environmental Science/Management or Economics.

Please contact, Email Karyn Morrissey for further information.

Low Carbon Liverpool: The Role of the Business Community in a Low Carbon Future

Discussion meeting

By Alex Nurse

Last Week (7th February), Low Carbon Liverpool hosted a seminar focusing on the business community and how it can engage with low carbon.
Held at Liverpool Community College’s Vauxhall campus, and chaired by our own Dr Peter North, we heard from Chris Benson (Benson Signs), Mike Bakewell (CT Investment Partners) and Justin Smith (Assistant Principal at the Community College).
Chris Benson spoke passionately about his own experiences greening his own business over the last twelve years, saying that a series of smaller steps can be more effective than trying to modify everything at once.  He argued that the cumulative effect has left his business far more efficient without the outlay of funding everything in one go.
Mike Bakewell then spoke about the business models that are emerging to help support small scale initiatives, and the importance of getting people to understand what is available to them.
Then, audience members engaged with the panel on the importance of sharing best practice case studies, particularly in the printed media, to show what can be achieved and the benefits to be had, as well as making the various funding and support structures well known.

The morning concluded with Justin Smith showing interested parties around the College’s Environmental Technology Centre, which provides training to install the latest in environmentally efficient technologies such as Solar Panels, Rainwater Catchment and Under-floor Heating.

The key take-home messages from the morning were twofold:

  • Firstly, that there is no substitute for enthusiasm in these matters. Being keen and engaged in running a business in the most efficient way possible can deliver benefits on a number of fronts, particularly to your operating costs.
  • Secondly, if you are interested, don’t shy away from a piecemeal approach. By building up your resilience over a number of years, across a number of individual projects you can end up with a business/organisation that is deeply low carbon without having to undergo fundamental, overnight change.

Ultimately, whole day brings to mind a proverb: “Those who say it can’t be done are often interrupted by those who are doing it”. Many of the people we heard from today exemplify this outlook.

For more info see: lowcarbonliverpool.com

Temporary Post Available

HIEF funding through the University has provided a short term post in Business Gateway, seconded to the Department of Geography and Planning.  The post is about external engagement and requires close working with a range of external companies. We are looking for a student/post-doctorate, ideally between contracts, this is a temporary full-time post, to start ASAP up until the end of June 2013. The post will be at a grade 4 spine-point 14, on a pro rata salary of £19,056 p.a*.

The concept is to work with companies to  discover how climate proofed they think they are and how they run through the evidence and decision making process using climate change information.  The work is really more social science focused, with Professor Andy Morse’s team providing the climate science back stop.  We really want to see how much commercial interests use climate data, where they get it from and the level of their engagement. Obviously we do not want to pry too much on commercially sensitive areas.

Drs Karyn Morrissey and Pete North will provide some support especially at project design from a social science perspective.

We have one or two companies (large multinationals) in mind that the University has already established links.  We also have contacts with SMEs. 

Further details about the post can be discussed with Andy Morse (A.P.Morse@liv.ac.uk or 0151 794 2879). The post will close, at the latest,  on Friday 15th February and interested parties are recommended to get in touch as soon as possible.

 * subject to final confirmation

Experiments in Physical Geography – the 2nd semester begins

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By Richard Chiverrell

The 2nd semester really got under way yesterday with the 6/7 hours of non stop fun in the University of Liverpool’s New ‘Central Teaching Laboratory’ (CTL). 54 students converged on the 1st floor Environmental and Archaeological Sciences Laboratory for the 1st Year modules Experiments in Physical Geography (ENVS154) and Theory and Experiments in Earth Surface Processes (ENVS163) modules meeting the teaching team; Rich Chiverrell, Andy Plater, John Boyle, Andreas Lang and Janet Hooke ably supported by the very excellent postgraduate demonstrators and technicians from the CTL and Geography. Using new equipment and purpose-designed experiments the class worked in small groups (5-6 people) on 10 concurrent practical sessions, bringing life to flumes, river catchment simulation, XRF’s, microscopes, laser granulometers, flame photometers and spectrometers, sediment deformation equipments, more new shiny toys than you can shake a stick at……

The exercises explored how

  • How do variations in dirt cover on ice affects melting rates?
  • How can we use lake sediment records to measure both long-term soil erosion
    rates and carbon sequestration?
  • How do slope gradients and catchment cover (vegetation and urban) affect storm flow response?
  • What  regulates the delivery of sediments from catchments to lakes?
  • Why do slopes fail and soils erode?
  • Is the recent infilling of the Dee Estuary due to sea-level rise or sediment
    accretion?
  • Do changes in sand dune sediment composition reflect changes in wind speed and deflation?
  • What main factors control the rate of chemical weathering in soils?
  • Can particle size data be used to distinguish beach and river deposits?

Practical learning