Ocean temperatures around Australia have warmed 0.7°C since 1910-1929, with south-west and south-eastern waters warming fastest (HIGH confidence)

Carbon dioxide dissolving in the oceans has lowered pH by 0.1 units since 1750, representing a 30% increase in hydrogen ion (acid) concentration (HIGH confidence)

Global sea levels have risen by 20 cm over 1870-2004 (HIGH confidence)

Strong interannual wave directional variability associated with ENSO on eastern coast (MEDIUM-HIGH confidence)

Southward flow has strengthened so warmer, saltier water is now found 350 km further south compared to 60 years ago (HIGH confidence)

Loss of algal habitat off eastern Tasmania associated with a southward range expansion of a sea urchin assisted by the strengthening of the East Australian Current and warmer temperatures (HIGH confidence)

Sea surface warming has led to extensive coral bleaching events and declines in coral condition on the Great Barrier Reef and on north-western reefs (HIGH confidence).

Warmer sand temperatures, from increased air temperature, has increased mortality of sea turtle eggs and hatchlings at the Mon Repos rookery in south-east Qld (HIGH confidence)

What is likely to happen in this century?

Australian ocean temperatures will be 1°C warmer by 2030 and 2.5°C warmer by 2100 (HIGH confidence), with the greatest warming in south-eastern waters (HIGH confidence)

Frequency and severity of mass coral-bleaching events will increase as temperatures warm, leading to declines in coral reef health (HIGH confidence).

Ocean acidification will reduce coral growth rates making reefs more susceptible to erosion and disturbance from storms (HIGH confidence)