The Role of Internal Tides in Supplying Nutrients to Coral Reefs

Abstract

Coral reefs, vital yet vulnerable ecosystems, hinge significantly on various ecological and oceanographic processes, among which the role of internal tides in nutrient upwelling is paramount. This research delineates a pioneering exploration into the complex dynamics of internal tides and their resulting impact on nutrient transport to global coral reef ecosystems, bridging a notable gap in worldwide exploration and understanding of this phenomenon. Employing comprehensive global climatology and bathymetric datasets, a novel approach to mapping internal tide-induced nutrient transport to coral reefs is presented. The study emphasises the essential interplay between ocean topography and internal tides in influencing kinetic energy distribution and consequent upwelling of nutrients. Of the 11 globally dispersed locations investigated, the Coral Triangle emerged as particularly noteworthy, revealing substantial nutrient uplift potential with vertical displacement (σZ) values of 512.57 m for M2, 267.61 m for S2, and 113.31 m for K1, and a mean nutrient depth at 200 m, indicative of consistent access to deep-seated nutrients. In stark contrast, regions such as French Polynesia exhibited a dissonance between nutrient mean depths (250.00 m) and σZ values (33.64 m for M2, 3.6 m for S2, and 1.18 m for K1), implying limited nutrient access via internal tides. Such heterogeneity in internal tide and nutrient interactions across various locations, from the nutrient-rich Coral Triangle to the less accessible French Polynesia, illuminates the multifaceted relationships between internal tides and coral reef nutrient dynamics. This research, as a maiden voyage into the global mapping of internal- mediated nutrient transport to coral reefs, underscores the ecosystem for nuanced, location- specific examinations and lays a foundational framework for future research, potentially steering sustainable marine conservation strategies amidst the tide escalating challenges of climate change and anthropogenic impacts.