A marine heatwave is lifting ocean temperatures off the coast of New South Wales to levels not seen in decades as the state is pummelled by severe storms.
The marine temperatures appear to be reaching levels not seen in nearly 80 years, with satellite data showing ocean surfaces three degrees Celcius above normal.
Professor Moninya Roughan said ocean temperatures at a site five kilometres from Port Hacking, Sydney, are approaching an all-time high for January.