Marine ecologists are warning that the increasing frequency and duration of marine heatwaves poses a threat to the ecological balance of the seas.
Research by Dr Pippa Moore from Aberystwyth University and colleagues from across the globe has shown that the annual incidence of marine heatwaves – where unusually high sea temperatures persist for five days or more at a time – rose by 54% between 1925 and 2016.
The work is based on satellite and in-situ observations of sea surface temperature taken between 1900 and 2016.
The findings, Longer and more frequent marine heatwaves over the past century, which also point to an accelerating trend since 1982, were published in Nature Communications on Tuesday 10 April 2018.
Dr Moore, a Reader in Marine Ecology at Institute of Biological, Environmental and Rural Sciences, said:
“Recent evidence demonstrates that marine heatwaves can have far-reaching ecological impacts, leading to species range shifts, impacts on fisheries and political tensions.”
“Our understanding of marine heatwaves and their impacts lags behind that of atmospheric heatwaves in terrestrial systems and also behind our knowledge of the ecological impacts of decadal scale warming.”
“However our research shows that marine heatwaves have increased in duration and frequency in the last 100 years, with much of this attributable to anthropogenic climate change, suggesting that ecological and economic impacts are only likely to increase with future climate warming.”
The authors suggest that given the likelihood of continued sea surface warming throughout the 21st century and the accelerating trend observed in recent decades, a continued global increase in marine heatwaves can be expected in future with important implications for marine biodiversity.