Australians protest prime minister for denying climate change as Sydney is covered in smoke from bushfires

Protesters in smoke-covered Sydney kicked off a fresh round of global protests against climate change on Friday, with activists and schoolchildren picketing the headquarters of bushfire-ravaged Australia's ruling party.

Hundreds of people gathered at the conservative Liberal party's offices to heed the call to action from 16-year-old climate change campaigner Greta Thunberg.

The protests have taken on extra urgency in Australia -- the country's southeast has been devastated by hundreds of damaging bushfires in recent weeks.

The protestors -- brandishing placards that read "You're burning our future" and chanting "we will rise" -- turned out as Sydney was again enveloped in toxic smoke caused by the fires that has blanketed the city for much of the last month.

Six people have died and hundreds of homes have been destroyed in the crisis, which scientists say has been worsened by rising temperatures.

Drought and unseasonably hot, dry and windy conditions have fuelled the unprecedented blazes.

The target of the protesters' ire was Prime Minister Scott Morrison, who has angrily denied any link between the fires and climate change while defending his support for fossil fuels.

"Our government's inaction on the climate crisis has supercharged bushfires," said school strike leader Shiann Broderick. "People are hurting. Communities like ours are being devastated. Summer hasn't even begun."

Australia, with a population of 25 million, has low carbon emissions compared with the planet's biggest polluters, but is one of the world's leading coal exporters.

"The suggestion that (in) any way shape or form that Australia, accountable for 1.3 percent of the world's emissions, that the individual actions of Australia are impacting directly on specific fire events, whether it's here or anywhere else in the world, that doesn't bear up to credible scientific evidence," Morrison claimed earlier this month.

Missed targets

Protests are expected later in the day in Melbourne, Brisbane and in cities across the world.

Last month, millions of people took to the streets in nearly every major global city for a series of "climate strikes".

The latest demonstrations come as 200 nations prepare to gather in Madrid next week for a 12-day UN climate conference.

The meeting will focus largely on finalising the "rulebook" for the 2015 Paris climate treaty, which becomes operational in 2021.

Scientists have warned that efforts to cap warming to 1.5 Celsius are failing, and that carbon emissions - which are on the rise -- would need to fall 7.6 percent a year to meet the target.

The UN has reported that greenhouse gas levels in the atmosphere, the main driver of climate change, hit a record high last year.

The organisation has also warned that global temperatures are on pace to rise almost four Celsius by the end of the century -- an increase that could make some places virtually unhabitable.