Great Meteor Seamount Circulation Revisited: Insights Into Cold-Water Coral Habitat Potential

Abstract

Seamounts play a crucial role in shaping deep-sea ecosystem structure, influencing ocean circulation, enhancing biological productivity, and supporting diverse marine life. The Great Meteor Seamount (GMS), is the largest seamount in the North Atlantic and a key ecological feature in the regional network of the Protected Areas of the Azores Archipelago, but remains poorly understood in terms of small-scale physical-biological interactions. Using a new high-resolution setup of the FlexSem hydrodynamic model, we analyze ocean circulation and water mass properties around GMS over a 9-month period. The results reveal a persistent anticyclonic re-circulation along the upper seamount slopes and doming of isopycnals above the summit. Variations in density and temperature drive two distinct circulation and mixing regimes: A cold, dense period with bottom-intensified Taylor cap circulation and strong vertical coupling, and a warm, stratified period with enhanced stratification and reduced vertical mixing. The high resolution of the model makes it possible to compare habitat-suitability maps for benthic filter-feeding organisms with maps of internal wave slope characteristics, revealing a key role of internal wave induced mixing in supporting cold-water corals and other benthic filter-feeding communities. The study highlights the significance of biophysical interactions at the seamount and emphasizes the need for further research into small-scale processes that support biological growth.