The city center is in lockdown. Black Hawk helicopters are patrolling the skies. Boats are combing the Brisbane River. Six thousand police have come from interstate and abroad. This is the biggest peacetime security crackdown in the nation's history.

This city's corporate sector is also running scared. Businesses shifted out of the city's Central Business District (CBD), prior to the Group of 20 (G-20) Leaders' Summit on Saturday and Sunday. Some are even nervous about the political implications of their actions. The Brisbane Airport Corporation banned a digital climate change billboard, causing an international stir. Australian Prime Minister Tony Abbott has refused to put climate change on the agenda, despite international calls.



The airport's head of corporate relations, Rachel Crowley, told DW the message was too political. The ad featured a farmer who lost $25,000 (17,500 euros) worth of grapes in one day last year, when temperatures touched 46 degrees Celsius (115 degrees Fahrenheit) at his South Australian vineyard.

Campaign initiator, Dermot O'Gorman, said the idea was to encourage people to tweet G-20 leaders, asking them to include climate change as a standalone item on the summit agenda. The WWF-Australia chief executive told DW he was "surprised and disappointed by the rejection."

"Australia is a great democracy with a proud tradition of freedom of expression. G-20 leaders from all over the world have started arriving here and it is not a good look for institutions like the airport to be blocking this sort of communication."

In a DW interview with Australia's Human Rights Commissioner, Tim Wilson said he personally would not have made such a move. The ban has obviously backfired creating more media attention around the world than the ad would have otherwise.

But the freedom-of-expression campaigner - formally in charge of climate change policy at the Institute of Public Affairs - denied the issue is swept under the carpet in Australia, the world's largest polluter per capita. "There has never not been continuous debate. In fact, for many years it was the most significant public policy that was debated in Australia," he laughed.

Australia recently became the first developed nation to repeal carbon laws that put a price on greenhouse gas emissions. It would have hit the mining companies (that make billions from the country's resources). They would have passed on the costs to consumers in the form of higher electricity bills. The government's move was seen as pandering to short-sighted voters and setting a bad example for the rest of the world.

Yet, Wilson argued: "Emissions trading schemes don't drive the innovation that you need. What they drive is deployment of existing technology. But existing technology isn't actually effective in dealing with the challenge."

There is truth to his argument, but it is something that requires discussion - at a global level. That is what the Australian government is hindering by leaving climate change off the official agenda at the G-20 conference. It is ironic, considering that Brisbane is in drought - the state's most widespread on record. And this weekend will be hot, with temperatures forecast to top 40 degrees.