Scientists have issued a warning that regulations outlined in the Paris Agreement will not be enough to stop the collapse of Greenland and Antarctic ice sheets.
Under the Paris Agreement drafted in 2015, countries agreed to limit global warming to less than 2degC pre-industrial levels.
But a new report from Victoria University and the Universite Libre de Bruxelles published in Nature Climate Change The ice sheet may have tipping points at or slightly above the 1.5-2 degC threshold.
Victoria University of Wellington's Professor Tim Naish reports that "IPCC Special Report on Global Warming of 1.5degC, and we are close to 1.5degC."
"Without some degree of direct carbon extraction from the atmosphere, we are unlikely to avoid it," he says.
If the ice sheets collapse, the report says it could lead to irreversible loss of mass and drainage basins. The impact of rising sea levels would be catastrophic for New Zealand.
New Zealand's pledge under the Paris Agreement will be reduced to 30 percent below 2005 levels by 2030. It was revealed last year that the cost of the New Zealand economy will reach $ 1.4 billion every year for a decade.
"We are very close to triggering irreversible changes in the polar ice sheets," says Professor Christine Hulbe of Otago University, commenting on the new report.
"The threshold for irreversible ice loss in both Greenland and Antarctica is somewhere between 1.5 and 2 deg C global mean warming. We're already at a bit more than 1degC warming.
"Even if we meet the Paris targets and keep the warming in check, we're still committed to continuing the ice loss over the 21st century, and it will continue sea level rise."
Victoria University of Wellington's Rob McKay notes that melting differs between hemispheres, with Melting controlled by atmospheric warming and Antarctica by oceanic warming.
But the temperature threshold to reach these tipping points in both regions is between 1.5 and 2 degrees Celsius, he says, which "suggests that even if we do meet the Paris climate agreement targets, we will be extremely close to the point of return for accelerated retreat .
"While this is going to be over, it's going to be over the next few years.
The researchers concluded that urgent research is required on the subject to better improve future projections.