Rising sea levels will reduce extreme temperature variations in tide-dominated reef habitats

• Published in: Science advances Vol. 2; no. 8; p. e1600825
• Main Authors: Lowe, Ryan Joseph, Pivan, Xavier, Falter, James, Symonds, Graham, Gruber, Renee
• Format: Journal Article
• Language: English
• Published: United States American Association for the Advancement of Science 01-08-2016
• Subjects: Australia; Climate Change; Coral Reefs; Ecosystem; Marine Ecology; SciAdv r-articles; Seawater; Sunlight; Temperature; Tidal Waves; thermodynamics; ocean temperature; reef morphology; Tides; coral reefs; sea level rise
• ISSN: 2375-2548; 2375-2548
• DOI: 10.1126/sciadv.1600825

Temperatures within shallow reefs often differ substantially from those in the surrounding ocean; therefore, predicting future patterns of thermal stresses and bleaching at the scale of reefs depends on accurately predicting reef heat budgets. We present a new framework for quantifying how tidal and solar heating cycles interact with reef morphology to control diurnal temperature extremes within shallow, tidally forced reefs. Using data from northwestern Australia, we construct a heat budget model to investigate how frequency differences between the dominant lunar semidiurnal tide and diurnal solar cycle drive ~15-day modulations in diurnal temperature extremes. The model is extended to show how reefs with tidal amplitudes comparable to their depth, relative to mean sea level, tend to experience the largest temperature extremes globally. As a consequence, we reveal how even a modest sea level rise can substantially reduce temperature extremes within tide-dominated reefs, thereby partially offsetting the local effects of future ocean warming.