This risk assessment combines the knowledge presented in earlier chapters of the Report to provide an assessment of current and potential threats to the Great Barrier Reef and is an important step in predicting the future of the ecosystem.

The greatest threats facing the Great Barrier Reef ecosystem are from climate change. The individual threats of increasing sea temperature, ocean acidification and rising sea level are assessed as very high risk to the ecosystem and they will act across the entire Region. Their impact will be compounded by each other and by other existing regional and local threats.

The most serious, regional-scale risks are catchment runoff, coastal development and some aspects of extractive use. These threats have the potential to work in combination to weaken the resilience of the Great Barrier Reef and therefore its ability to recover from serious disturbances (such as major coral bleaching events) that will become more frequent in the future.

While climate change will affect all parts of the Great Barrier Reef, the compounding effects of threats associated of catchment runoff, coastal development and some extractive use means that the nearshore environment next to developed areas is the most at risk.

• Scoping and assessing current threats

• Overall threat to the ecosystem

• Assessment summary