Making space for proactive adaptation of rapidly changing coasts: a windows of opportunity approach

Coastlines are very often places where the impacts of global change are felt most keenly, and they are also often sites of high values and intense use for industry, human habitation, nature conservation and recreation. In many countries, coastlines are a key contested territory for planning for climate change, and also locations where development and conservation conflicts play out. As a “test bed” for climate change adaptation, coastal regions provide valuable, but highly diverse experiences and lessons. This paper sets out to explore the lessons of coastal planning and development for the implementation of proactive adaptation, and the possibility to move from adaptation visions to actual adaptation governance and planning. Using qualitative analysis of interviews and workshops, we first examine what the barriers are to proactive adaptation at the coast, and how current policy and practice frames are leading to avoidable lock-ins and other maladaptive decisions that are narrowing our adaptation options. Using examples from UK, we then identify adaptation windows that can be opened, reframed or transformed to set the course for proactive adaptation which links high level top-down legislative requirements with local bottom-up actions. We explore how these windows can be harnessed so that space for proactive adaptation increases and maladaptive decisions are reduced

Wave transformation across a macrotidal shore platform under low to moderate energy conditions

We investigate how waves are transformed across a shore platform as this is a central question in rock coast geomorphology. We present results from deployment of three pressure transducers over four days, across a sloping, wide (~200 m) cliff-backed shore platform in a macrotidal setting, in South Wales, United Kingdom. Cross shore variations in wave heights were evident under the predominantly low to moderate (significant wave height < 1.4 m) energy conditions measured. At the outer transducer 50 m from the seaward edge of the platform (163 m from the cliff) high tide water depths were 8+ m meaning that waves crossed the shore platform without breaking. At the mid platform position water depth was 5 m. Water depth at the inner transducer (6 m from the cliff platform junction) at high tide was 1.4 m. This shallow water depth forced wave breaking, thereby limiting wave heights on the inner platform. Maximum wave height at the middle and inner transducers were 2.41 and 2.39 m respectively and significant wave height 1.35 m and 1.34 m respectively. Inner platform high tide wave heights were generally larger where energy was up to 335% greater than near the seaward edge where waves were smaller. Infragravity energy was less than 13% of the total energy spectra with energy in the swell, wind and capillary frequencies accounting for 87% of the total energy. Wave transformation is thus spatially variable and is strongly modulated by platform elevation and the tidal range. While shore platforms in microtidal environments have been shown to be highly dissipative, in this macro-tidal setting up to 90% of the offshore wave energy reached the landward cliff at high tide, so that the shore platform cliff is much more reflective

Interdisciplinary palimpsest: visual representations of coastal change combining digital craft and geomorphology

From rocks to clay, a shared interest in natural materials and their physical transformation provided the initial common ground for an interdisciplinary art-geoscience collaborative project that also opened up a novel and engaging public communication channel. Scientific data collected for a location-based geomorphology mapping project was collaboratively re-interpreted and re-presented as a craft installation by using digital technologies and hand-crafted processes. The project explored how creative practice can uncover and broaden narratives, layering interpretations whilst respecting and embracing the need for accurate visual representation of scientific data. As the practice-based element of a broader digital craft PhD research programme, the project effectively demonstrated an enlarged field of practice for digital craft. The collaboration resulted in a large-scale, porcelain panelled, wall-mounted installation for public exhibition and has led to subsequent significant unforeseen developments in the scope and outlook of research work undertaken by the collaborators. This paper reflects on the synergies between disciplines that were uncovered and how project challenges were met. We conclude that the project work acted as a ‘boundary object’ for the two collaborating parties, able to represent different values and fulfil different objectives for each party at the same time, while also moving forward practice for both

The influence of light attenuation on the biogeomorphology of a marine karst cave: a case study of Puerto Princesa Underground River, Palawan, the Philippines

Karst caves are unique biogeomorphological systems. Cave walls offer habitat for microorganisms which in-turn have a geomorphological role via their involvement in rock weathering, erosion and mineralisation. The attenuation of light with distance into caves is known to affect ecology, but the implications of this for biogeomorphological processes and forms have seldom been examined. Here we describe a semi-quantitative microscopy study comparing the extent, structure, and thickness of biocover and depth of endolithic penetration for samples of rock from the Puerto Princesa Underground River system in Palawan, the Philippines, which is a natural UNESCO World Heritage Site. Organic growth at the entrance of the cave was abundant (100% occurrence) and complex, dominated by phototrophic organisms (green microalgae, diatoms, cyanobacteria, mosses and lichens). Thickness of this layer was 0.28 ± 0.18 mm with active endolith penetration into the limestone (mean depth = 0.13 ± 0.03 mm). In contrast, phototrophs were rare 50 m into the cave and biofilm cover was significantly thinner (0.01 ± 0.01 mm, p < 0.000) and spatially patchy (33% occurrence). Endolithic penetration here was also shallower (< 0.01 mm, p < 0.000) and non-uniform. Biofilm was found 250 m into the cave, but with a complete absence of phototrophs and no evidence of endolithic bioerosion. We attribute these findings to light-induced stress gradients, showing that the influence of light on phototroph abundance has knock-on consequences for the development of limestone morphological features. In marine caves this includes notches, which were most well-developed at the sheltered cave entrance of our study site, and for which variability in formation rates between locations is currently poorly understood

Geomorphological control on boulder transport and coastal erosion before, during and after an extreme extra-tropical cyclone

Extreme wave events in coastal zones are principal drivers of geomorphic change. Evidence of boulder entrainment and erosional impact during storms is increasing. However, there is currently poor time coupling between pre- and post-storm measurements of coastal boulder deposits. Importantly there are no data reporting shore platform erosion, boulder entrainment and/or boulder transport during storm events – rock coast dynamics during storm events are currently unexplored. Here, we use high-resolution (daily) field data to measure and characterise coastal boulder transport before, during and after the extreme Northeast Atlantic extra-tropical cyclone Johanna in March 2008. Forty-eight limestone fine-medium boulders (n = 46) and coarse cobbles (n = 2) were tracked daily over a 0.1 km2 intertidal area during this multi-day storm. Boulders were repeatedly entrained, transported and deposited, and in some cases broken down (n = 1) or quarried (n = 3), during the most intense days of the storm. Eighty-one percent (n = 39) of boulders were located at both the start and end of the storm. Of these, 92% were entrained where entrainment patterns were closely aligned to wave parameters. These data firmly demonstrate rock coasts are dynamic and vulnerable under storm conditions. No statistically significant relationship was found between boulder size (mass) and net transport distance. Graphical analyses suggest that boulder size limits the maximum longshore transport distance but that for the majority of boulders lying under this threshold, other factors influence transport distance. Paired analysis of 20 similar sized and shaped boulders in different morphogenic zones demonstrates that geomorphological control affects entrainment and transport distance – where net transport distances were up to 39 times less where geomorphological control was greatest. These results have important implications for understanding and for accurately measuring and modelling boulde

Knowledge management across the environment-policy interface in China: What knowledge is exchanged, why, and how is this undertaken?

Global to local environmental policy-making is increasingly evidenced-based. Knowledge management (KM) is increasingly used by environmental scientists and policymakers, to deliver evidence-based policy and practice. There is thus an urgent need to identify whether and how knowledge is exchanged between knowledge producers and users in environmental science fields. Here we apply an assessment framework developed in social medicine to identify what forms of environmental knowledge are exchanged, and why and how they are exchanged. We focussed on China, as international research to better manage Chinese ecosystem services is rapidly-increasing, yet, how to best integrate this into political decision-making and the public realm remains a challenge. How KM is practiced in China is unknown. We addressed this through: 1) a systematic analysis of published KM research in China compared to global trends; 2) evaluating KM for environmental policy and management in China; 3) quantitative surveys of Chinese (n = 72) and British (n = 16) scientists researching Chinese environmental problems. The systematic literature review of two databases identified two key findings. One, of 291 papers that considered KM there were no papers in the environmental sector examining the science-policy-practice interface in China. Two, only 13 of 423 potentially relevant papers explicitly examined KM for environmental topics, notably for agriculture and information exchange (the 'What?'). Most papers reported a one-way interaction between scientists and users (the 'How?'), used to change practice (the 'Why?'). Our survey showed significantly-less awareness and use of two-way knowledge exchange (KE) methods by Chinese scientists. The paucity of documented KM research and limited evidence for two-way interaction show KE at the environmental science-policy-practice interface in China is limited. Promotion of KE practice may benefit environmental policy-making in China. We have also shown that conceptual frameworks for mapping and assessing KE practice from social medicine can be usefully adapted for examining environmental science – policy interfaces

Ecological enhancement of coastal engineering structures: passive enhancement techniques

The rock type used in coastal engineering structures impacts biodiversity, but its effect has been understudied to date. We report here on whether different combinations of rock material and rock mass properties can improve habitat suitability and early phase ecological outcomes on coastal engineering structures. We examine two coastal engineering schemes that used different granites during construction. At site one, Shap granite boulders with a high number of cm-dm2 surface features (e.g. ledges) were deliberately positioned during construction (called passive enhancement), to a) maximise the provision of cm-dm scale intertidal habitat and b) determine which scale of habitat is best for ecological enhancement. At site two, Norwegian granite boulders were installed without passive enhancement, allowing for a direct comparison. Passive positioning of Shap granite boulders led to an increase in limpet (Patella vulgata, Linnaeus, 1758) abundance within two years but few limpets were recorded on the non-enhanced Norwegian granite. Positioning of boulder thus exerts a strong control on the mm and mm-dm scale geomorphic features present, with clear ecological benefits when suitable features are selected for and optimally positioned (i.e. passive enhancement) to maximise habitat features. An EcoRock scoring matrix was developed to aid in the selection of the most ecologically suitable rock materials for coastal engineering worldwide; this can help improve habitat provision on engineered structures in a rapidly warming world

Erosion of rocky shore platforms by block detachment from layered stratigraphy

The majority of shore platforms form in rocks that are characterised by layered stratigraphy and pervasive jointing. Plucking of weathered, joint and bed bounded blocks is an important erosion process that existing models of platform development do not represent. Globally, measuring platform erosion rates have focused on microscale (< 1 mm) surface lowering rather than mesoscale (0.1‐1 m) block detachment, yet the latter appears to dominate the morphological development of discontinuity rich platforms. Given the sporadic nature of block detachment on platforms, observations of erosion from storm event to multi‐decadal timescales (and beyond) are required to quantify shore platform erosion rates. To this end, we collected aerial photography using an unmanned aerial vehicle to produce structure‐from‐motion‐derived digital elevation models and orthophotos. These were combined with historical aerial photographs to characterise and quantify the erosion of two actively eroding stratigraphic layers on a shore platform in Glamorgan, south Wales, UK, over 78‐years. We find that volumetric erosion rates vary over two orders of magnitude (0.1‐10 m3 yr‐1) and do not scale with the length of the record. Average rates over the full 78‐year record are 2‐5 m3 yr‐1. These rates are equivalent to 1.2‐5.3 mm yr‐1 surface lowering rates, an order of magnitude faster than previously published, both at our site and around the world in similar rock types. We show that meso‐scale platform erosion via block detachment processes is a dominant erosion process on shore platforms across seasonal to multi‐decadal timescales that have been hitherto under‐investigated

A multiscale analysis of social-ecological system robustness and vulnerability in Cornwall, UK

Understanding social-ecological system (SES) feedbacks and interactions is crucial to improving societal resilience to growing environmental challenges. Social-ecological systems are usually researched at one of two spatial scales: local placed-based empirical studies or system-scale modelling, with limited efforts to date exploring the merits of combining these two analytical approaches and scales. Here, we take a multiscale interdisciplinary approach to elucidate the social dynamics underpinning cross-sectoral feedbacks and unintended consequences of decision-making that can affect social-ecological system vulnerability unexpectedly. We combined empirical place-based research with the Robustness Framework, a dynamic system level analysis platform, to analyse the characteristics and robustness of a coastal SES in Cornwall, UK. Embedding place-based empirical analysis into a broader institutional framework revealed SES feedbacks and “maladaptations”. We find that decentralisation efforts coupled with government austerity measures amplify second-order (reputational) risks. This prompted temporal policy trade-offs, which increased individual and community vulnerability and reduced social-ecological system robustness, impeding local adaptation to climate change. We identify opportunities to ameliorate these maladaptations by (1) implementing coordination rules that can guide policymakers in instances of conflicting coastal management pressures, and (2) recognising how second-order risks influence decision-making. This work demonstrates the strengths of combining local and regional analyses to assess the robustness of social-ecological systems exposed to environmental changes, such as climate change and sea level rise. Our results show how analysis of the multiscale effects of climate policies, decision-making processes and second-order risks can usefully support local climate change adaptation planning