A climate scientist is describing Judith Collins as 'complacent' after she lashed out at the "political left" for "hugely" overstating the impacts of climate change.
The National MP aired her frustrations in a Facebook post on Sunday night, telling her 21,000 followers there are a "few home truths that no-one on the political left, and few on the right, are willing to discuss".
She said despite the rhetoric in some reports warning of catastrophe, the world "will not end" if global warming is not limited to 1.5degC above pre-industrial levels.
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"There is a major 'reality gap' in the debate on global warming," Collins said.
"I believe this has been allowed to manifest as a result of any politician, scientist or economist who questions global warming policy instantly being ostracised as the equivalent as a global warming 'denier'."
She said while the costs of global warming are "real", there is "no indication they are insurmountable".
Victoria University of Wellington Professor James Renwick, a weather and climate researcher, told Newshub "that may be" true today.
But he said warming above 1.5degC would "displace millions more people, would threaten a much greater range of terrestrial and marine ecosystems, and would increase risks across energy, food, and water sectors".
Collins made reference to an October 2018 report about global warming by the Intergovernmental Panel on Climate Change (IPCC), a United Nations body made up of the world's best experts on the topic.
It said if Earth warms by 2degC, hundreds of thousands of species could go extinct, natural environments will die and coastal communities will be flooded out of existence.
Its key finding was that meeting a 1.5degC target is possible but would require "deep emissions reductions" and "rapid, far-reaching and unprecedented changes in all aspects of society".
New Zealand agreed to help keep global average temperatures below 2degC and pursue efforts to limit it to 1.5degC, when it signed up to the Paris Agreement in 2015.
Collins doubts that goal can be met, saying despite New Zealand's efforts, there is "almost no chance" the world will avoid reaching 1.5degC.
The IPCC report does say that global warming will likely rise to 1.5degC above pre-industrial levels between 2030 and 2052 if warming continues to increase at the current rate.
But some scientists are more optimistic. When the report came out, NIWA scientist Dr Jonny Williams said maintaining temperatures below 1.5degC will be "challenging, but certainly not impossible".
Victoria University Professor Dave Frame told Newshub it's "certainly true" that 2degC looks tough and 1.5degC looks "very unlikely", but it "may be better to confront it head-on than to pretend it away".
He also pointed to research showing that it's not geophysically impossible.
Collins pointed to the IPCC's finding that even if all of the ambitions under the Paris Agreement were implemented, it would not limit global warming to 1.5degC.
It says the ambitions would lead to global greenhouse gas emissions of 52-58 billion tonnes of CO2 per year by 2030, but the reduction needed is about half of that: 25-30 billion tonnes by 2030.
"There is almost zero chance the globe will achieve such a reduction," Collins said.
Renwick agreed that the pledges made in the Paris Agreement "do not get us" to 2degC. But he said doing nothing at all would put us at 4degC.
"Above two degrees of warming, we lock in the irreversible melting of the West Antarctic ice sheet, guaranteeing around 5 metres of sea level rise over coming centuries, with around 1 metre by the end of this century."
Collins said it is "fantasy land" to think that "after 30 years of negotiations, countries like China, Brazil and India, who are rightfully focused on poverty eradication, are going to suddenly sacrifice economic development for climate change".
Renwick said, "Sadly, she may be right."
But he added, "Leadership is what is required urgently, not the complacent attitude displayed by Judith Collins."
Frame praised National MPs who have shown a "good grasp of the problem", pointing to climate change spokesperson Todd Muller and former minister Tim Groser.
"There are a few MPs and ex-MPs who embrace climate scepticism and sometimes even outright climate denial. Those positions are at least as far from the evidence as the ones Collins is critiquing."
Collins suggested it's problematic that the Zero Carbon Bill - which is yet to have its second reading - would create a legally binding objective to limit global warming to no more than 1.5degC with a net zero carbon approach.
She said the "problem" is that "the likely impacts of climate change are being hugely overstated by the media and political left".
She also said there is a "massive gap between what politicians say they think the world should do and the plain reality of global emissions".
Collins took aim at Climate Change Minister and Greens co-leader James Shaw, criticising him for labelling National's "political opposition" as the new "climate denialism" in his speech at this year's Green Party Conference.
"I can't accept the proposal we are expected to just never question any legislation that has the aim of reducing emissions, no matter what the cost, simply for moral reasons," Collins said.
"Economists and politicians have to be allowed to offer considered and balanced perspectives."
Shaw said he would not engage in a debate about "these thoroughly debunked ideas".
"I'm going to stay focused on the policy work to keep us below 1.5degC of warming, so that we don't lapse into an irreversible feedback loop of warming that puts us at risk."
Frame said Shaw was out of line to call any criticism of Green views "the new denialism".
But he said it is "pretty clear that pretending the problem away isn't working, and its failure is more manifest by the year".
National leader Simon Bridges said Collins is "right".
"This isn't an emergency, I don't think... We need practical, sensible actions, but we're not going to sit by and let our economy be ruined by radical, meaningless proposals... We're not going to see farm production go down the toilet."
He said National will be pushing back on some aspects of the Zero Carbon Bill before offering more support, such as the methane reduction target.
The Climate Change Response (Zero-Carbon) Amendment Bill would require methane emissions to be reduced by at least 10 percent by 2030 and between 24 and 47 percent by 2050.
"The methane target is unrealistically high... There is not enough regard for the economic impact of change."
The Bill's second reading is expected in the next fortnight.