Two members of the Climate Change Authority have resigned, with one accusing the government of being beholden to rightwing, anti-science “extremists” in its own party and in the media.

John Quiggin told Guardian Australia he informed the federal minister for environment and energy, Josh Frydenberg, of his resignation on Thursday. It follows the resignation of fellow climate change authority member, Danny Price, who quit on Tuesday.

“The government’s refusal to accept the advice of its own authority, despite wide support for that advice from business, environmental groups and the community as a whole, reflects the comprehensive failure of its policies on energy and the environment,” Quiggin said.

“These failures can be traced, in large measure, to the fact that the government is beholden to rightwing anti-science activists in its own ranks and in the media. Rather than resist these extremists, the Turnbull government has chosen to treat the vital issues of climate change and energy security as an opportunity for political point-scoring and culture war rhetoric.”

Quiggin said his immediate reason for resigning was the government’s failure to respond to the authority’s third report of the special review into potential climate policies, which the government had requested and which it was legally required to respond to.

“The government has already indicated that it will reject the key recommendations of the review, particularly the introduction of an emissions intensity scheme for the electricity industry.”

Quiggin said he didn’t believe there was anything to be gained “by giving objective advice based on science and economic analysis to a government dominated by elements hostile to both science and economics”.

Price told Guardian Australia he had resigned because he “didn’t think it was appropriate for a member of a government agency to be openly critical of government policy”.

“I think the authority does really good work, but I didn’t think I could stay if I was going to continue to criticise the government’s policy making and I didn’t see any chance that it would get any better,” he said.

“I really hate the complete ad hocery of it all … the idea that anything at all can be thrown out by a government in a political panic.”

Quiggin was appointed to the authority in 2012, and Price in 2015. Both were appointed for five-year terms.

The Climate Change Authority’s special review was undertaken last year, and recommended the government institute two emissions trading schemes and strengthen regulations if it was to meet Australia’s 2030 emission reduction targets.

The report was criticised by the Climate Institute, the Greens, and other climate groups and experts criticised elements of the report, and in August Guardian Australia revealed a split in the ranks of the authority, with three members writing a dissenting report.

However many groups – including the Business Council of Australia, Energy Networks Australia, retailer Energy Australia, electricity provider AGL, the Climate Change Authority, the National Farmers Federation and the CSIRO – have also called for the introduction of an emissions intensity trading scheme.

Frydenberg canvassed a trading scheme in December, but the the idea was dumped after three days following objections from senior ministers.

The government’s openness to a scheme has also been cited as a reason for Cory Bernardi’s resignation from the party in February.

The Climate Change Authority was set up in 2011 as an independent statutory agency, and the Coalition has maintained that it should be abolished after failing to get its legislation to do just that through the Senate.

Frydenberg told Guardian Australia: “the government thanks both Danny Price and John Quiggin for their service and the government will continue to engage constructively with the authority”.

The Greens climate and energy spokesman, Adam Bandt, said the government’s “dangerous pandering to climate change deniers” had left it friendless.

“When added to previous resignations, this exodus is the equivalent of half the reserve bank board resigning over the government’s economic policies.”