Tony Abbott has questioned the "so-called settled" science about climate change, a month after dropping his view that Australia should pull out of the Paris climate agreement.
The former prime minister insisted he was a realist when asked about his position on climate change during his election campaign launch in Manly on Friday.
"The so-called settled science is not quite as settled as people say, and that's my position," he told reporters.
"Nevertheless we have only got one planet; we should do what we reasonably can to rest lightly upon it."
Despite this questioning, Mr Abbott said he does believe climate change happens and that mankind makes a contribution.
"We should do what we reasonably can to reduce emissions," he said.
"What we shouldn't do though, is turn our economy upside down in what turns out to be a futile green gesture."
The comments come as the former prime minister is locked in a fight with independent candidate Zali Steggall for his seat of Warringah on Sydney's northern beaches.
Pursuing effective action on climate change is a key campaign platform for Ms Steggall, a barrister and former Olympic alpine skier.
She suggested on Friday she may not support a re-elected Morrison government unless it did more to act on the problem.
"I look forward to the coalition coming to the table on climate change," she told Sky News.
"That's what the Australian people are asking them to do."
In a candidate debate last month, Mr Abbott backflipped on his previously stated view that Australia should pull out of the Paris climate agreement, saying the government had "lost its emissions obsession now".