We revisit the challenges and prospects for ocean circulation models following Griffies et al. (2010). Over the past decade, ocean circulation models evolved through improved understanding, numerics, spatial discretization, grid configurations, parameterizations, data assimilation, environmental monitoring, and process-level observations and modeling. Important large scale applications over the last decade are simulations of the Southern Ocean, the Meridional Overturning Circulation and its variability, and regional sea level change. Submesoscale variability is now routinely resolved in process models and permitted in a few global models, and submesoscale effects are parameterized in most global models. The scales where nonhydrostatic effects become important are beginning to be resolved in regional and process models. Coupling to sea ice, ice shelves, and high-resolution atmospheric models has stimulated new ideas and driven improvements in numerics. Observations have provided insight into turbulence and mixing around the globe and its consequences are assessed through perturbed physics models. Relatedly, parameterizations of the mixing and overturning processes in boundary layers and the ocean interior have improved. New diagnostics being used for evaluating models alongside present and novel observations are briefly referenced. The overall goal is summarizing new developments in ocean modeling, including: how new and existing observations can be used, what modeling challenges remain, and how simulations can be used to support observations.
There is a growing impetus to increase marine protected areas coverage globally from 6% to 30% in 2030. Successfully establishing and maintaining marine protected areas require incorporating public preferences into their establishment and management. We investigate the role of alternate management regimes (top-down and bottom-up) on preferences for marine protected areas and the marginal rate of substitution between natural and man-made capital using a case study in the Asia-Pacific region of Okinawa, Japan. We implemented a choice experiment survey to infer which attributes of marine protected areas are most important for the respondents. We use our survey results to calculate respondents’ willingness to support marine protected areas in Okinawa. This study contributes to the policy debate on management of marine protected areas with empirical data that characterizes the perception of Okinawan residents with respect to the role of local coastal communities (bottom-up) compared to central government based agencies (top-down) management. We extend the analysis and estimate the trade-offs to residents in Okinawa between natural capital (i.e. coral coverage and marine biodiversity attribute) and man-made capital (i.e. restrictions on coastal development). We find that the underlying management regime affects the local residents’ valuation of the marine protected area with residents showing a higher willingness to support bottom-up management regimes. There is also substantial differences in the willingness to support different characteristics of marine protected areas by management type. Finally, we find that the marginal rate of substitution between natural capital and man-made capital varies by management type such that residents would need to be compensated relatively less in terms of man-made capital in the presence of a policy scenario that proposes an increase in natural capital under a bottom-up management regime.
Scotland's National Marine Plan (NMP) consists of various objectives and policies which aim to support sustainable development within the marine environment while upholding the integrity of the ecosystem through the adoption of an ‘ecosystem approach to planning’. While this approach is not new, momentum has been gaining in research for accounting for the relationships between physical, chemical, and biological elements, functions, and processes of an ecosystem in marine spatial planning. Given that the NMP is under statutory review in 2017–2018 following three years since its publication, the outputs of this paper aim to inform the review by exploring how national and sectoral objectives and policies address ecosystem service sections and phases by using the UK National Ecosystem Assessment classification system as a reference. The analysis demonstrates that cultural benefits are the most accounted for, while the cultural final services which underpin such benefits are the least accounted for. Furthermore, there are no national objectives or policies which account for provisioning final services. The paper provides 12 distinct policy recommendations to enhance the uniformity of ecosystem services in the NMP.
Ecosystem service (ES) trade-offs have been broadly recognized and studied over the past decade. However, how to coordinate the relationships among ES trade-offs to achieve win–win outcomes remains a considerable challenge for decision makers. Here, we summarize the current approaches applied to minimize ES trade-offs for win–wins and analyze the trade-offs among different ESs and their drivers. Based on a systematic review of the literature from 2005 to 2018, we identified 170 potentially relevant articles, 47 of which were selected for the review, recording 70 actual or potential trade-offs. Analysis of these case studies showed that trade-off pairs between provisioning services and regulating services/biodiversity accounted for 80% of total pairs. Furthermore, more than half of the ES trade-offs were driven by land use/land cover changes. Harvest and resource demand, natural resource management, and policy instruments were also among the main drivers. Four approaches to coordinate ES trade-offs were identified, including ecosystem, landscape-scale, multi-objective optimization, and policy intervention (and other) approaches. Based on the above, we recommend a rigorous understanding of the roles of different stakeholders, spatial scales of management, trade-off dynamics, and integrated implementation of diverse approaches to coordinate ES trade-offs in order to better achieve win–win outcomes.
In Southwest Florida, a variety of human impacts had caused widespread losses of seagrass coverage from historical conditions. St. Joseph Sound and Clearwater Harbor lost approximately 24 and 51%, respectively, of their seagrass coverage between 1950 and 1999, while Tampa Bay and Sarasota Bay had lost 46% and 15%, respectively, of their seagrass coverage between 1950 and the 1980s. However, over the period of 1999 to 2016, the largest of the six estuaries, Tampa Bay, added 408 ha of seagrass per year, while the remaining five estuaries examined in this paper added approximately 269 ha per year. In total, seagrass coverage in these six estuaries increased 12,171 ha between the 1980s and 2016. Focused resource management plans have held the line on nitrogen loads from non-point sources, allowing seagrass resources to expand in response to reductions in point source loads that have been implemented over the past few decades.
The global ocean has warmed substantially over the past century, with far-reaching implications for marine ecosystems1. Concurrent with long-term persistent warming, discrete periods of extreme regional ocean warming (marine heatwaves, MHWs) have increased in frequency2. Here we quantify trends and attributes of MHWs across all ocean basins and examine their biological impacts from species to ecosystems. Multiple regions in the Pacific, Atlantic and Indian Oceans are particularly vulnerable to MHW intensification, due to the co-existence of high levels of biodiversity, a prevalence of species found at their warm range edges or concurrent non-climatic human impacts. The physical attributes of prominent MHWs varied considerably, but all had deleterious impacts across a range of biological processes and taxa, including critical foundation species (corals, seagrasses and kelps). MHWs, which will probably intensify with anthropogenic climate change3, are rapidly emerging as forceful agents of disturbance with the capacity to restructure entire ecosystems and disrupt the provision of ecological goods and services in coming decades.
Understanding how no-take zones (NTZs) shape the population dynamics of key herbivores is crucial for the conservation and management of temperate benthic communities. Here, we examine the recovery patterns of sea urchin populations following a high-intensity storm under contrasting protection regimes in the NW Mediterranean Sea. We found significant differences in the recovery trends of Paracentrotus lividus abundance and biomass in the five years following the storm. The P. lividus populations outside the NTZ recovered faster than the populations inside the NTZ, revealing that predation was the main factor controlling the sea urchin populations inside the NTZ during the study period. Arbacia lixula reached the highest abundance and biomass values ever observed outside the NTZ in 2016. Our findings reveal that predation can control the establishment of new sea urchin populations and emphasize top-down control in NTZs, confirming the important role of fully protected areas in the structure of benthic communities.
Shallow coral reefs provide food, income, well-being and coastal protection to countries around the Indian Ocean and Asia. These reefs are under threat due to many anthropogenic stressors including pollution, sedimentation, overfishing, sea surface warming and habitat destruction. Ocean acidification interacts with these factors to exacerbate stress on coral reefs. Effective solutions in tackling the impact of ocean acidification require a thorough understanding of the current adaptive capacity of each nation to deal with the consequences. Here, we aim to help the decision-making process for policy makers in dealing with these future challenges at the regional and national levels. We recommend that a series of evaluations be made to understand the current status of each nation in this region in dealing with ocean acidification impacts by assessing the climate policy, education, policy coherence, related research activities, adaptive capacity of reef-dependent economic sectors and local management. Indonesia and Thailand, are selected as case studies. We also highlight general recommendations on mitigation and adaptation to ocean acidification impacts on coral reefs and propose well-designed research program would be necessary for developing a more targeted policy agenda in this region.
Getting an overall view of primary data available from existing Earth Observation Systems and networks databases for the Mediterranean Sea, the main objective of this paper is to identify temporal and geographic data gaps and to elaborate a new method for providing a prioritisation of missing data useful for end-users that have to pinpoint strategies and models to fill these gaps. Existing data sources have been identified from the analysis of the main projects and information systems available. A new method to perform the data gap analysis has been developed and applied to the whole Mediterranean basin as case study area, identifying and prioritise geographical and temporal data gaps considering and integrating the biological, geological, chemical and physical branches of the total environment. The obtained results highlighted both the main geographical data gaps subdividing the whole Mediterranean Sea into 23 sub-basins and the temporal data gaps considering data gathered since 1990. Particular attention has been directed to the suitability of data in terms of completeness, accessibility and aggregation, since data and information are often aggregated and could not be used for research needs. The elaborated inventory of existing data source includes a database of 477 data rows originated from 122 data platforms analysed, able to specify for each dataset the related data typologies and its accessibility. The obtained results indicate that 76% of the data comes from ongoing platforms, while the remaining 25% are related to platforms with non-operational monitoring systems. Since the large amount of analysed records includes data gathered in inhomogeneous ways, the prioritisation values obtained for each identified data gap simplify the data comparison and analysis. Lastly, the data gaps inventory contains geographic and temporal information for any missing parameter at the whole basin scale, as well as the spatial resolution of each available data.
Climate change is poised to exacerbate coastal erosion. Recent research has presented a novel strategy to tackle this issue: dual wave farms, i.e., arrays of wave energy converters with the dual function of carbon-free energy generation and coastal erosion mitigation. However, the implications of sea level rise – another consequence of climate change – for the effectiveness of wave farms as coastal defence elements against shoreline erosion have not been studied so far. The objective of this work is to investigate how the coastal defence performance of a dual wave farm is affected by sea level rise through a case study (Playa Granada, southern Iberian Peninsula). To this end, a spectral wave propagation model, a longshore sediment transport formulation and a one-line model are combined to obtain the final subaerial beach areas for three sea level rise scenarios: the present situation, an optimistic and a pessimistic projection. These scenarios were modelled with and without the wave farm to assess its effects. We find that the dual wave farm reduces erosion and promotes accretion regardless of the sea level rise scenario considered. In the case of westerly storms, the dual wave farm is particularly effective: erosion is transformed into accretion. In general, and importantly, sea level rise strengthens the effectiveness of the dual wave farm as a coastal protection mechanism. This fact enhances the competitiveness of wave farms as coastal defence elements.