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Biogeochemical and ecosystem interactions with socio-economic activity in the global ocean

Periodic Reporting for period 3 - BIGSEA (Biogeochemical and ecosystem interactions with socio-economic activity in the global ocean)

Reporting period: 2019-07-01 to 2020-12-31

The question of how global humanity can live better, while remaining within planetary boundaries, is one of the most important challenges of the 21st century. Elements of this challenge are being addressed by many thousands of researchers around the world, but these efforts are often isolated within disciplines, and there is no existing unification of natural science aspects with social aspects within a common quantitative framework. The BIGSEA project (www.earthsystemdynamics.org/iesd/bigsea) addresses this shortfall by aiming to develop a novel integrated, grid-based model framework that resolves both human and natural components, and to apply this to fundamental questions regarding interactions between climate, biogeochemistry, fishing and the marine ecosystem. This ambitious goal requires assembling a team with specific aspects of inter-disciplinary expertise, developing a new quantitative framework for simulating humans, identifying critical links of understanding, proposing new hypotheses and testing them against data.
We have published the first global coupled marine fishery-ecosystem model and shown that continual improvements in fishing technology dominate all other factors in the long run. We discovered surprisingly strong relationships between features of the ocean environment and differences in the observed historical development of fisheries around the world, revealing a novel link between economic development and the ecosystem. We have also produced the first global description of seasonal fishing patterns in the global high seas using satellite data. We have developed a new model for simulating spatially-variable fishing fleets and dynamic management, including small-scale coastal fisheries and their interaction with industrial fleets. We have carried out fieldwork to assess critical missing links in knowledge regarding the motivation and well-being of small-scale fisheries in low income countries, which do not follow the same dynamics as industrial fisheries, and discovered unexpectedly high well-being in non-monetized communities. We have produced a first global estimate of interactions between ocean biogeochemistry and all marine fish, and made a surprising discovery regarding the probable iron limitation of fish in parts of the open ocean that led to a new understanding of the role of animals in iron cycling. We collected an unprecedented global size-based organismal dataset, which are using to provide the first formal test of a long-standing theory regarding the size distribution on all life. Finally, inspired by the climate model simulation approach, we developed a novel method for projecting the future wellbeing of humans based on material and non-material factors.
Unexpected results were achieved in terms of ocean biogeochemistry, regarding links between fish and the iron cycle: first, that fish struggle to survive in large parts of the high seas due to insufficient dietary iron, and second, that the feces of fish are uniformly enriched in iron relative to their food, and therefore provide a relatively iron-rich food source. The low iron supply has been well known for its relevance to phytoplankton and photosynthesis, but never previously linked to animal ecology. This work has major implications for marine ecology and food security. We have also produced a novel global fishery model with interactive, dynamic management, which is a world first, and used it to provide the first-ever assessment of global fishery dynamics following an abrupt climate shock. We were the first to show the existence of very high subjective well-being in a non-monetized society and, as an unexpected spin-off, a new conceptual advance allowed the quantitative projection of future life satisfaction for all humans to the year 2050.
Map of simulated global harvest in BOATSv1