1592 / 2024-10-13 09:00:16

Aerobic constraints on marine habitat from ocean weather to climate change

Climate change,hypoxia,traits,metabolism,ecosystems,Earth System Models

Session 59 - Impacts of Climate and Biogeochemical Extremes on Marine Organisms and Ecosystems

The biogeography of marine species is shaped by the energetic demands of ecological activity, allowing trait-based habitat limits to be predicted from the confluence of the ocean’s temperature and O₂ distributions.  Intra-seasonal ocean variability, including episodic extremes of heat or hypoxia, can also have strong non-linear impacts on the aerobic balance of organisms, but the relationship between such short-term ocean ‘weather’ and long-term climate impacts on habitability is poorly understood. In this talk, I will present recent research into the role of ocean weather in modulating aerobic habitat, with a focus on two key findings from tropical reef ecosystems. First, even brief periods of episodic hypoxia can alter long-term species co-existence and ecosystem health.  Second, climate warming appears to increase the frequency and intensity of ‘metabolic storms’, a compound ocean weather event defined by high temperature and low O₂ levels. Together these findings highlight the need for more high-frequency sampling of aerobic conditions in dynamic coastal areas, especially in tropical reef environments.  Moreover, the findings imply that projections of future extinction risk in tropical ecosystems due to warming and O₂ loss may be underestimated by current Earth System Models, which do not adequately resolve ocean weather phenomena.