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1. Was Scotland covered by an ice sheet during Marine Isotope Stage 4? Insights from the pre‐Last Glacial Maximum marine terraces of northwest Scotland

   https://doi.org/10.1002/jqs.70000  

   Simms, Alexander R; DeWitt, Regina; Bradley, Sarah L; Huffman, Emily; Best, Louise; Bradwell, Tom; Lloyd, Jeremy M; Kachuck, Samuel B (August 2025, Journal of Quaternary Science)

   ABSTRACT Raised shorelines provide important constraints on past sea levels, glacial isostatic adjustment (GIA), and rates and directions of vertical crustal motion. Although most raised shorelines across NW Scotland relate to post‐Last Glacial Maximum (LGM) glacial‐isostatic rebound, many undated shorelines lie above the marine limit established from isolation basins. Here, we present new optically stimulated luminescence (OSL) ages for a raised marine terrace at an elevation of 28 m in Slaggan Bay of NW Scotland. Four OSL ages suggest the feature is pre‐LGM, likely Marine Isotope Stage (MIS) 3. Global mean sea levels (GMSL) during MIS 3 are thought to have been ~40–60 m below present across most of the globe. We use a pair of GIA models to determine what ice sheet and sea‐level scenarios might provide an explanation for these anomalously high sea levels during MIS 3. Our results suggest that in the absence of tectonic activity, such high MIS 3 shorelines across NW Scotland require a MIS 4 ice sheet in Scotland, with postglacial rebound of the crustal depression following its demise during MIS 3 responsible for the elevated shoreline features at that time. 

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2. Chapter 21: Knowledge infrastructures for sustainable energy transitions: marine renewable energy in Scotland

   https://doi.org/10.4337/9781839100710.00032  

   Hirsch, S. L. (January 2021, Research handbook on energy and society)

   J. Webb, F. Wade (Ed.)
3. Age summary for Scotland project

   https://doi.org/10.6084/m9.figshare.30794939  

   DeWitt, Regina (December 2025, figshare)

   OSL ages of samples collected in SW Scotland 

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4. Sampling-Dependent Transition Paths of Iceland–Scotland Overflow Water

   https://doi.org/10.1175/JPO-D-22-0172.1  

   Beron-Vera, F. J.; Olascoaga, M. J.; Helfmann, L.; Miron, P. (April 2023, Journal of Physical Oceanography)

   Abstract In this note, we apply transition path theory (TPT) from Markov chains to shed light on the problem of Iceland–Scotland Overflow Water (ISOW) equatorward export. A recent analysis of observed trajectories of submerged floats demanded revision of the traditional abyssal circulation theory, which postulates that ISOW should steadily flow along a deep boundary current (DBC) around the subpolar North Atlantic prior to exiting it. The TPT analyses carried out here allow attention to be focused on the portions of flow from the origin of ISOW to the region where ISOW exits the subpolar North Atlantic and suggest that insufficient sampling may be biasing the aforementioned demand. The analyses, appropriately adapted to represent a continuous input of ISOW, are carried out on three time-homogeneous Markov chains modeling the ISOW flow. One is constructed using a high number of simulated trajectories homogeneously covering the flow domain. The other two use much fewer trajectories which heterogeneously cover the domain. The trajectories in the latter two chains are observed trajectories or simulated trajectories subsampled at the observed frequency. While the densely sampled chain supports a well-defined DBC, whether this is a peculiarity of the simulation considered or not, the more heterogeneously sampled chains do not, irrespective of the nature of the trajectories used, i.e., observed or simulated. Studying the sampling sensitivity of the Markov chains, we can give recommendations for enlarging the existing float dataset to improve the significance of conclusions about long-time-asymptotic aspects of the ISOW circulation. 

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5. Siccar Point, Scotland, and the role of mental models

   Shipley, Thomas F; Tikoff, Basil (November 2024, GSA today)