The Turnbull government's recent embrace of coal-fired power shows it has "abandoned all pretense of taking global warming seriously", Climate Change Authority member Clive Hamilton said, explaining why he resigned from the agency.
Professor Hamilton, who teaches public ethics at Charles Sturt University, sent his resignation letter to Environment and Energy Minister Josh Frydenberg on Friday, saying it was "perverse" that the government would be boosting coal when 2016 marked the hottest year on record.
Prime Minister Malcolm Turnbull used his National Press Club speech last week to call for support for so-called "clean coal-fired power plants" to provide "reliable baseload power" while meeting Australia's carbon emissions goals.
Professor Hamilton said the comments were "completely irresponsible and perhaps the sharpest indicator yet just how completely Malcolm Turnbull has capitulated to the hard right of the Liberal Party".
"If the new coal-fired power plants were built, it would make the government's already weak 2030 [carbon] reduction target unattainable," he said in his letter.
"Deeper cuts in the subsequent decades, essential to limit the worst impacts of warming, would be off the table.
"Professor Hamilton told Fairfax Media the authority "no longer has any role in the development of climate change policy in Australia".
Mr Frydenberg said the government was "unapologetic that our priority as we transition to a lower emissions future is energy security and affordability".
"We are smashing our 2020 target by 224 million tonnes and we have an ambitious 26 to 28 per cent emissions reduction target by 2030 on 2005, which on a per capita basis is one of the highest in the G20," he said.
The Senate blocked repeated efforts by Abbott government to scrap the authority.
In October 2015, then environment minister Greg Hunt appointed five new members including Wendy Craik as chairwoman in a move the Greens said amounted to a stacking of Coalition-leaning appointees.
"In its first years, the authority did great work," Professor Hamilton said, including recommending Australia should aim to cut 2000-level emissions by 40-60 per cent by 2030.
The current government target is for a cut of as much as 28 per cent from 2005 levels by 2030, which amounts to about 20 per cent below 2000 levels.
The authority, though, "has become a shadow of its former self", particularly since the departure of former Reserve Bank governor Bernie Fraser as its chairman, Professor Hamilton said.
Last September, Professor Hamilton and fellow authority member David Karoly, issued a dissenting report, accusing the authority of failing to give the government independent advice.
The two claimed its Special Review of Australia's climate goals and policies was based on "reading from a political crystal ball" rather than meeting its own terms of reference.
A relationship banned under traditional law.
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