Stimulus details: Ocean warming and sea-surface temperature (SST) increases

impact chain for tropical coastal areas / ocean warming (click nodes to view details):
Ocean warming, including increases in sea-surface temperatures, has a direct impact on reef-building corals as it decreases their growth rates[4] and induces bleaching. For example, the 1998 ENSO events led to the bleaching of many Indian Ocean coral communities, with up to 90% mortality in shallow areas.[5] The delayed effects of coral bleaching include predator concentration, increased bio-erosion, susceptibility to disease and parasites, and decreased capacity for wound healing.[6]

The direct socio-economic effects of bleaching on coastal communities include decreases in diving tourism[7], declines in reef fish stocks[8] and general losses of coral ecosystem services (e.g., regulating) because of the decline in coral cover. Coastal erosion also increases because the reefs can no longer serve as protective barriers.[5]

Declines in coral cover will reduce the habitat available for reef fish, which will also be directly affected by ocean warming because it will weaken their physiological performance and change their behaviours, especially in early life and reproduction phases.8 Range shifts are expected to occur for subtropical and temperate species.[9]

Fish can potentially adapt through acclimatisation over multiple generations, but this adaptation ability may be compromised by other pressures such as overfishing. Coral reefs also have the potential to adapt through the acquisition and maintenance of more thermally tolerant symbionts (algae living in symbiosis with corals).[10] However, anthropogenic pressures such as nutrient enrichment and overfishing can greatly affect coral tolerance of and recovery from thermal stress.[11, 12] Coastal management should better account for the cumulative, synergistic and mounting stresses arising from climate change and concurrent human activities.


[4]    Cantin, N. E., Cohen, A. L., Karnauskas, K. B., Tarrant, A. M., McCorkle, D. C., 2010. Ocean warming slows coral growth in the central Red Sea. Science 329, 322-325.

[5]    Wilkinson, C., Lindén, O., Cesar, H., Hodgson, G., Rubens, J., Strong, A. E., 1999. Ecological and socioeconomic impacts of 1998 coral mortality in the Indian Ocean: an ENSO impact and a warning of future change? Ambio 28.

[6]    Glynn, P. W., Mate, J. L., Baker, A. C., Calderon, M. O., 2001. Coral bleaching and mortality in Panama and Ecuador during the 1997-1998 El Nino-Southern Oscillation event: spatial/temporal patterns and comparisons with the 1982-1983 event. Bulletin of Marine Science 69, 79-109.

[7]    Zeppel, H., 2012. Climate change and tourism in the Great Barrier Reef Marine Park. Current Issues in Tourism 15, 287-292.

[8]    Munday, P. L., Jones, G. P., Pratchett, M. S., Williams, A. J., 2008. Climate change and the future for coral reef fishes. Fish and Fisheries 9, 261-285.

[9]    Lloyd, P., Plaganyi, E. E., Weeks, S. J., Magno-Canto, M., Plaganyi, G., 2012. Ocean warming alters species abundance patterns and increases species diversity in an African sub-tropical reef-fish community. Fisheries Oceanography 21, 78-94.

[10]    Baker, A. C., Starger, C. J., McClanahan, T. R., Glynn, P. W., 2004. Coral reefs: corals' adaptive response to climate change. Nature 430, 741-741.

[11]    McClanahan, T., 2008. Response of the coral reef benthos and herbivory to fishery closure management and the 1998 ENSO disturbance. Oecologia 155, 169-177.

[12]    Wooldridge, S. A., Done, T. J., Thomas, C. R., Gordon, I. I., Marshall, P. A., Jones, R. N., 2012. Safeguarding coastal coral communities on the central Great Barrier Reef (Australia) against climate change: realizable local and global actions. Climatic Change 112, 945-961.
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