Challenges to climate change adaptation in coastal small towns:Examples from Ghana, Uruguay, Finland, Denmark, and Alaska

The ability of a coastal settlement to adapt to climate change is largely dependent upon access to a range of resources, which many coastal towns and small cities lack. Coastal small towns of less than 10,000 are therefore at a significant disadvantage compared to larger settlements when it comes to adaptation. One way to begin to overcome this disadvantage is to compare coastal small towns in order to identify efficiencies and support knowledge sharing. In this article we present and analyse five case studies of coastal small towns: Fuvemeh, Ghana; Kiyú, Uruguay; Hanko, Finland; Lemvig, Denmark; and Nome, Alaska, USA. A number of key outcomes and lessons were identified which highlights the need for a formal network of international coastal small towns to encourage and develop knowledge sharing practices going forward. A further lesson is the importance of using a range of indicators in order to establish the regional/national importance of a town. Basing this solely on population size can result in an erroneous interpretation of the significance (and therefore adaptive capacity) of a coastal small town. Finally, despite many barriers to adaptation in coastal small towns, being small offers some potential advantages, such as the possibility of being able to form a community consensus more easily, using 3D visualisations for adaptation planning, and having managed realignment as a realistic management option. It is imperative that climate change resilience in coastal small towns is increased by focussing on overcoming barriers and developing appropriate adaptation approaches by governments, non-governmental organisations, business, and researchers

Climate Risks and Reasons for Concern along the Uruguayan Coast of the Rio de la Plata Estuary

The Uruguayan coast of the Río de la Plata river estuary (RdlP) is 300 km long. It encompasses an inner tidal river and a middle and an outer estuary. The RdlP is a micro-tidal system dominated by river inflow from the Paraná and Uruguay rivers and southern winds with increasingly frequent wind-induced storm surges impacting the coast. The El Niño-Southern Oscillation influences the river inflow, prevailing winds, water/sea level and beach erosion. First, we focus on the IPCC Reasons for Concern (RFC) about the trends of climate risks threatening the Uruguayan coast. The trends and maxima of air temperature, water/sea levels and river inflow in three coastal stations from 1980 to 2019 show temporal changes attributable to climate change and El Niño-Southern Oscillation (ENSO). The occurrence, evolution and Montecarlo simulations of return periods of the yearly river flow and sea level height maxima provide metrics of RFC to categorise the climate risks from past to projected future and the level of risk from undetectable to very high. Then, we summarise some current and expected climate risks and present the current adaptation framework and some expected impacts. The RFC has increased, reaching moderate to high-risk levels

Form function of sulcus acusticus of the sagittal otolith in seven Sciaenidae (Acanthuriformes) species using geometric morphometrics (southwestern Atlantic)

15 pages, 12 figures, 1 tableThe morphology of otoliths determines the function they perform, and it is influenced by genetic and environmental factors. Knowing those relationships is necessary to understand the role of hearing in fish. The objectives of this work were: exploring the shape of the sulcus of the sagittal otolith in seven species of Sciaenidae, in relation to sound production, and analyzing whether the shape and size of the sulcus can be used as a phylogenetic character. For this purpose, geometric morphometry analysis was carried out using landmarks data. It was found that there is an influence of size on the shape of the sulcus, and significant differences were found between the shapes of the sulcus (permutational multivariate analysis of variance). Three general shapes of the sulcus were identified (using principal component analysis, canonical variate analysis, and clustering): (1) in species that produce sounds at dominant frequencies 350 Hz, the ostium showed a flattened ovoid shape, and the cauda increased its length; (3) the species that do not produce sounds, did not show any modifications, relative to the form of consensus. Despite finding sister species that presented similar sulcus shapes in the phylogeny, the results did not confirm that this can be used as a phylogenetic character. This work discusses whether the combined effects of phylogenetic legacy and natural functional selection have led to convergent evolution for the sulcus form. The differences presented by the sulcus of species that occupy the same clade, could indicate that there is a displacement of characters. The sagittal otolith and the sensory macula associated with the sulcus acusticus are highly plastic structures that are subject to strong evolutionary pressure in relation to environmental and behavioral factors, resulting in great variability in shapes that can be associated with a specific character. The variation in the shape of the sulcus would allow the analysed species to coexist in the same coastal soundscapes, without losing their particular hearing needs, even in case of overlapping their spatial and temporal distribution areasPrograma de desarrollo de las ciencias basicas (PEDECIBA)With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe