Report shows dramatic Antarctic change with global consequences
Climate change is having significant impacts on Antarctica's ice sheets, climate and life, with far-reaching global consequences, according to a new report from the Scientific Committee on Antarctic Research (SCAR).
The report, released on May 24 at the Antarctic Treaty Consultative Meeting in Berlin, shows that Antarctic ice sheets are melting, the continent's climate is changing, and the Southern Ocean is warming, becoming more acidic and losing oxygen.
Antarctica's changes have global impacts. Ice sheet contributions to global mean sea level rise will put nearly a billion people at risk from coastal flooding, more so if the upper end scenario of 2m sea level rise by the end of the century is realised. Changing Antarctic climates also mean impacts everywhere, especially extremes on some continents.
Locally, changing climates are already affecting the region's iconic whales, seals, penguins, and the krill they rely on. Emperor penguins may be all but gone by the end of the century unless urgent action is taken.
The SCAR report is led by Monash University Professor Steven Chown, Director of Securing Antarctica's Environmental Future (SAEF) and SCAR's Immediate Past President.
"Antarctica's changes have profound consequences for all of us," said Professor Chown.
"What's most unnerving is that we are documenting these changes already, but are unsure how large they'll actually become. We could be facing unmanageable adversity in our lifetimes if we don't act with urgency."
"Antarctica has always been our quiet, distant neighbour. Now there's no need to travel to visit it. It's right here, noisily disturbing the neighbourhood, threatening more to come. Higher sea levels, more extremes, less help with managing the global climate."
The report provides the globally agreed view on changes occurring and those that will take place on the Antarctic continent and in its surrounding Southern Ocean, which washes up against Australia's shores.
Concerningly, projections for sea level rise from the ice sheets over the next several decades are highly uncertain – Antarctic melt could help contribute to as much as 2 m of global sea level rise before the century is out.
Just 40 cm of global sea level rise turns a one in 100-year coastal flood event into an annual one – a scenario the planet is already committed to.
The report makes clear that adhering to, and preferably exceeding, the Paris Climate Agreement greenhouse gas emissions reductions targets will substantially lessen changes to the Antarctic and their implications for society.
Its messages have been developed specifically for the Parties to the Antarctic Treaty, who are gathering in Berlin for their 44th Annual Meeting. The Parties are those countries responsible for the environmental management of the Antarctic, including Australia. Professor Chown says the Parties have a real opportunity at this meeting to strengthen their responses to climate change to help the world deal with its most profound existential crisis.
As well as the lead author, two other authors are from Monash: Professor Andrew Mackintosh, Head of the School of Earth, Atmosphere and Environment, and SAEF Researcher Laura Phillips. Another is Monash PhD graduate and Mollie Holman awardee Dr Rachel Leihy.
"If we look after Antarctica we look after our future, and vice versa, it's that simple or that complicated," concluded Ms Phillips.
