As world leaders arrived in the northern city of Brisbane for the G20 summit, scores of Australians buried their heads in the sands of iconic Bondi Beach on Thursday to send a message to Prime Minister Tony Abbott about the dangers of climate change.

"Tony Abbott's refusal to include climate change on the G20 agenda and his government's overt attempts to stifle the renewable energy industry show that he is determined to keep his head buried in the sand on the most important issue of our time," said organiser Eden Tehan.

Since coming to power last year, Abbott's conservative government has scrapped a carbon tax designed to tackle climate change, fulfilling a key election promise.

It has also removed another tax on the profits of coal mining, while new investment in renewable energy has fallen 70 percent. Abbott has defended the use of fossil fuel coal as crucial to Australia's prosperity..

G20 leaders, including US President Barack Obama, meet in Brisbane on Saturday and Sunday with boosting global growth the main theme of their talks.