What Causes Heatwaves in the Ocean?

Neil John Holbrook, University of Tasmania, Institute for Marine and Antarctic Studies, Hobart, TAS, Australia, Hillary A Scannell, University of Washington, School of Oceanography, Seattle, WA, United States, Alexander Sen Gupta, Australian Research Council (ARC) Centre of Excellence for Climate Extremes and UNSW Climate Change Research Centre, Sydney, NSW, Australia, Jessica Benthuysen, Australian Institute of Marine Science, Perth, Western Australia, Australia, Ming Feng, CSIRO, Environment, Crawley, Western Australia, Australia, Eric C Oliver, Lisa Alexander, University of New South Wales, ARC Centre of Excellence for Climate Extremes, Sydney, NSW, Australia, Michael T Burrows, Scottish Marine Institute, Department of Ecology, Oban, United Kingdom, Markus Donat, University of New South Wales, Sydney, NSW, Australia, Alistair J Hobday, CSIRO Environment, Hobart, TAS, Australia, Pippa J Moore, Aberystwyth University, Institute of Biological, Environmental and Rural Sciences, Aberystwyth, United Kingdom, Sarah Perkins-Kirkpatrick, University of New South Wales, Climate Change Research Centre and ARC Centre of Excellence for Climate System Science, Sydney, NSW, Australia, Dan E Smale, Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth, United Kingdom, Sandra E Straub, The University of Western Australia, UWA Oceans Institute and School of Biological Sciences, Perth, WA, Australia and Thomas Wernberg, The University of Western Australia, UWA Oceans Institute and School of Biological Sciences, Perth, Western Australia, Australia
Abstract:
Marine heatwaves are ocean temperature extremes that persist for a defined period and are analogous to the more familiar heatwaves in the atmosphere. Marine heatwaves can cause devastating impacts on marine habitats and species, and lead to substantial economic losses for marine fisheries and aquaculture. Despite their significance, our understanding of heatwaves in the ocean is in its infancy relative to the much more extensively studied processes that underpin heatwaves in the atmosphere. This paper will discuss findings from a global assessment of the important local processes, large-scale climate modes and teleconnections that drive marine heatwaves. Our analysis comprises a detailed confidence assessment of the refereed literature (reported from 1950-2016) identifying the key processes that generate or modulate marine heatwaves in 22 case study regions across four ocean climate zones, combined with an analysis of daily sea surface temperatures over the satellite record. Clear patterns emerge, including coherent relationships between enhanced or suppressed marine heatwave occurrences with the dominant climate modes across most regions of the globe – an important exception being western boundary current regions where reports of marine heatwave events are few and ocean-climate relationships are complex. In this region, we pay close attention to the importance of oceanic eddies and Rossby waves as key to this understanding. These results provide a global baseline for future marine heatwave process and prediction studies.
Back to: Marine Heat Waves and Ocean Biogeochemical Extremes III Posters