Impacts of marine heatwaves

Marine heatwaves are areas where sea surface temperatures are elevated for extended periods of time. They have been observed in various locations around the world including the Pacific and Indian Oceans and the Mediterranean Sea. Climate change scenarios indicate increasing ocean temperature as well as heat content. In combination these conditions will lead to the more frequent occurrence of marine heatwaves. This chapter explores the impacts of increased frequency and intensity of marine heatwaves in terms of species mortality and changes in the timing of life cycles, range extensions and contractions. A range of ecological communities is analysed through a case study examining impacts on plankton, reefs, seagrasses, macroalgae, penguins, fish and marine pests and the dependent human systems.