Thermodynamics and hydrodynamics in an atoll reef system and their influence on coral cover

Research at Palmyra Atoll reveals that wave-driven mean flows play a critical role in maintaining lower weekly temperatures in backreef habitats, which correlates with higher coral cover. Spatial variations in coral cover were linked to temperature fluctuations on daily to weekly scales, with shallow terrace and backreef sites exhibiting high coral cover (>50%) due to these hydrodynamic processes. While tides influenced local flow, they had minimal impact on net heat transport. Buoyancy-driven flows within lagoons and cross-shore exchange in forereef environments were also significant. The study, based on field measurements from 2012 to 2014, suggests that reef areas with wave-driven temperature regulation are more likely to support coral survival under future warming conditions.

Rogers, J. S., Monismith, S. G., Koweek, D. A., Torres, W. I., & Dunbar, R. B. (2016). Thermodynamics and hydrodynamics in an atoll reef system and their influence on coral cover. Limnology and Oceanography, 61(6), 2191–2206. Portico. https://doi.org/10.1002/lno.10365