Merthyr Mawr Warren: Potential for Dune Reactivation dataset https://portal.medin.org.uk/portal/start.php?tpc=007_NRW_DS114691 This dataset is a compilation of work carried out to assess the geomorphological feasibility of sand dune reactivation at Merthyr Mawr Warren, based on a review of background environmental data, air photographs LiDAR data, a site visit and laboratory analysis of a limited number of sediment samples. The Merthyr Mawr dunefield is a sediment-starved system which is undergoing re-distribution of sandy sediment from the north-western part to the south-eastern part of the system. Photographic evidence indicates that bare sand and active dunes covered a large part of the area between the late 19th century and the late 1960’s, after which time the dunes became progressively stabilized by vegetation. The period of high dune mobility corresponded with a period of coastal erosion. No long-term wind or wave data are available for the area, but it is hypothesized that coastal erosion, frontal dune blowout development and inland dune mobility were encouraged by high average wind and wave energy conditions, and perhaps a higher frequency of severe storms. Conversely, the period of inland dune stability between the 1970’s and the present day was associated with beach accretion and foredune progradation. It is hypothesized that these changes were driven by lower average wind / wave energy conditions and lower frequency of severe storms. Bare sand and active parabolic dunes have only been maintained in areas where there is high visitor pressure or other anthropogenic disturbance. The purpose of this data capture was to help inform decisions that may result in potential re-mobilisation work, including impact on existing habitats and stakeholder interests. 20111130