Ciaran Nash (MSc)

MSc in Environmental Science

Ciaran Nash

E-mail: nashci@tcd.ie

LinkedIn: http://www.linkedin.com/in/CiaranNash

Bio:

I am originally from Oxford, England but have been living in Ireland since 2006 and in Dublin since 2011. I completed my undergraduate degree in Geography in Trinity College Dublin (TCD) in 2015 and I am currently pursuing research for my MSc in Environmental Sciences. I have an interest in Earth surface processes and geomorphology, interactions between society and landscape, natural processes and the built environment, and GIS as a tool for spatial problem solving.

Masters Abstract

A pilot study of moisture and salinity dynamics within the vadose zone of a transect of vegetated, temperate coastal dunes at Golden Strand, Achill Island, Co. Mayo was undertaken during the summer months of 2016. The behaviour of these environmental variables is of geomorphic importance given the many interrelationships between them and other variables such as a vegetation, precipitation, and sediment entrainment by the wind.
Previous research in coastal dune hydrology has commonly neglected to take into account moisture dynamics within the vadose (unsaturated) zone between 0 and 50 cm depth. It is precisely this zone that is most vulnerable to erosion from multiple sources and the zone where coastal plants begin to develop root systems. Improving our understanding of vadose dune hydrology is imperative given the predicted climatic changes for Europe, with more intense coastal storms and more frequent, short-duration, extreme precipitation events. Furthermore, the majority of western

European coastal dunes are relict landforms with limited contemporary sediment inputs (Carter, 1990; Jackson & Cooper, 2011) that have undergone stabilisation as a result of vegetation growth over the past fifty years. Stabilisation, and the relict nature of these systems, has led to increased vulnerability to large storm events. In the west of Ireland, coastal sand dunes offer protection to a unique coastal landscape – the machair.
Moisture and salinity dynamics were studied using a combination of capacitance probe technology, local weather data, and internal dune temperatures.

The influence of rainfall and salt spray were investigated as too was the location of each study site relative to the shoreline. It was observed that sites closer to the shore exhibited greater salinity concentrations and more variability than sites further inland. Moisture at the more seaward sites was found to be highly variable and generally lower in concentration than landward sites. Furthermore, moisture infiltration was found to be site-specific, with deeper infiltration observed at the most landward sites. Salt spray was found to be the primary emplacement mechanism of salinity within the study transect, while rainfall was found to act as a salt flushing mechanism within the dunes. Salinity concentrations are also variable at depth and some sites do not show significant variations in salinity at depths of 40 and 50 cm. It is suggested that precipitation changes resulting from modern climate change, and the predicted effects of larger, more intense coastal storms, will result in increased salt deposition on the dunes and more variable flushing rates within these surface features. This will likely feedback into the geomorphic stability of the system via vegetation changes.

This research is part of a larger EPA-funded project, ‘From source to sink: the response and recovery of coastal catchment
ecosystems to large perturbations’.

Education
2015 – 2016 MSc Environmental Sciences (TCD), 1st class honours
2011 – 2015 BA (Mod) Hons Geography (TCD), 1 st class honours.
Undergraduate thesis: ‘An Investigation into the Distribution of Sand Dune
Furrows in the Southern Hemisphere of Mars and the Possible Causes Behind Their Spatial Patterning’.