Extreme Climatic Events and High-Latitude Reef-Building: What Consequences from Global Climatic Change?

Particularly in high latitudes (and on reefs in extreme settings) reef-building by in situ framework production is strongly influenced by extreme climatic events that can cause coral mass mortality. Subsequent break- up of coral skeletons and heavy bioerosion remove the framework and can thus lead to a reef switch-off. Examples of such events are sea-surface-temperature anomalies, frequently associated with ENSO events, and extreme-wave-energy events frequently associated with tropical cyclones (hurricanes). For a series of high- latitude coral areas (Florida, South Africa, Red Sea, Arabian Gulf) in comparison with some tropical reef areas (Indonesia, Cayman, USVI) the effects of climatic teleconnections in the predicted global warming scenarios is explored. Factors examined for possible importance for high- latitude reef building processes are: increase in frequency of ENSO and teleconnected events, latitudinal changes in the tropical cyclone (hurricane) belts. Also warm-water delivery into the South Atlantic via Agulhas rings and the North Atlantic thermohaline circulation as well as the possible link between increased SST and emergent diseases is briefly revisited.