The Great Barrier Reef is a victim of climate change – but it could be part of the solution
A healthy ocean is vital for a healthy planet, and healthy coral reefs lie at the heart of ocean biodiversity W e are fast approaching unstoppable climate change. If we dont take drastic action to cut our global greenhouse gas emissions at the United Nations Climate Change Conference in Glasgow this November, our children and grandchildren will pay dearly for this failure. Already, average surface temperatures globally have risen 1.1C above the preindustrial levels of the late 1800s and limiting global warming to 1.5C is becoming increasingly challenging. A recent report by the Intergovernmental Panel on Climate Change (IPCC) stated that 70 to 90% of warm water coral reefs that exist today will have disappeared by the time we reach 1.5C. At 2C, coral reefs will be vanishingly rare. The sobering reality reported by the World Meteorological Organization is that on our current path, we are heading to global warming of over 3C before the end of this century. This would cause irreversible damage to marine ecosystems and the ocean as a whole. Science and recent experience tell us the consequences would be catastrophic globally this is clearly something we must avoid at all costs. Australias vast oceans, covering around 10 million square kilometres, are a case in point. Conditions here are changing rapidly. Marine species are turning up in places they have never been before and others are simply dying out. Even the Great Barrier Reef , one of our planets largest living structures, has been severely damaged by unprecedented marine heatwaves, triggering three mass coral bleaching events that reduced shallow water coral reefs by as much as 50% over just the last five years. A healthy ocean is vital for a healthy planet, and healthy coral reefs lie at the heart of ocean biodiversity. Home to a quarter of all ocean life, coral reefs provide services for humanity such as food and livelihoods, as well as protection from storms, erosion and flooding. These and other services have been estimated to provide at least $29.8bn each year to local economies. But these services are in serious jeopardy as we continue to emit greenhouse gases by burning fossil fuels, cutting down the worlds forests and destroying coastal habitats. The window to act is rapidly closing. This may sound shocking, but it is the unequivocal message science is giving us. At this juncture in human history, there is no sense in watering down these concerns. We must act, and act urgently. This is why the United Nations Decade of Ocean Science for Sustainable Development is so important for us all. By linking specific actions to relevant sustainable development goals, this global initiative provides the horizon that we must move towards if we are to save the ocean and, in turn, our planet. It also illustrates how relevant the ocean is to the solutions and actions we must take. The ocean doesnt have to be a victim of climate change. It can be a major solution to solving the climate crisis some would say our strongest ally. To assist our ally, we should be investing in the sustainable blue economy, converting shipping to non-fossil fuel energy sources and financing renewable offshore energy infrastructure. We should stop polluting and over-fishing the ocean and we must protect and restore blue carbon stocks associated with mangroves, wetlands and seagrasses. Known as carbon sinks, these diverse coastal habitats act like enormous sponges, continually cleaning our air by absorbing carbon and storing it out of the atmosphere. As well as reducing emissions to net zero as rapidly as possible, we must build the resilience of coral reefs so they can thrive in what will be a warmer climate. The challenge confronting us all is immense, but there is hope if we combine our ideas, efforts and resources. The UN Decade of Ocean Science for Sustainable Development provides a once-in-a-lifetime opportunity for countries to work together to give us the science we need for the ocean we want. And of course, the ocean we want relies on healthy coral reefs. Organisations like the Great Barrier Reef Foundation have joined this global effort to chart the best way forward. The Foundations Reef Recovery 2030 plan, which has been endorsed as a Decade of Ocean Science flagship action, will boost the resilience of reef ecosystems and the wellbeing of the people who rely on them. This decade-long collective effort aims to turn the tide on the decline of tropical coral reefs and urgently needs support from around the world. One thing is sure science must be our chief guide in these endeavours. We need the best science to develop bold, innovative ideas to protect coral reefs and slow the impacts of climate damage. We must think at our creative best, test new ideas and strategies and learn from our failures. The latter is most important if we are to successfully develop the necessary solutions in the urgent timeframe needed. It is imperative that we give the ocean the level of respect it commands as the source of life on this planet and devote our efforts and resources towards impactful action to save coral reefs and the ocean for future generations. Ambassador Peter Thomson is the United Nations Secretary Generals Special Envoy for the Ocean Professor Ove Hoegh-Guldberg, University of Queensland, is chief scientist at the Great Barrier Reef Foundation, and a fellow of the Australian Academy of Science