Warming index gives governments climate change flexibility

A New Zealand academic who co- wrote an international paper on managing climate change goals is calling for an overhaul of the way climate change pledges are assessed to avoid "indefinite procrastination" on the design of efficient mitigation policies.

Victoria University of Wellington Professor David Frame was one of four authors of a paper published Tuesday in the international scientific journal Nature Climate Change.

The paper argued that the "pledge and review" approach that will form the basis of commitments made at the United Nations climate change negotiations in December, presented an opportunity to explicitly link mitigation goals to the evolving climate response.

The researchers said mitigation strategies had to be robust and learning from trial and error allowed for evolving knowledge to be incorporated at low costs.

The researchers recommended an adaptive strategy based on an index of warming attributable to human influence, drawn from observed temperatures.

At the end of 2014, the rise in global mean temperature that could be attributed to the impact of people was calculated to be 0. 91 degrees centigrade.

Such an index was not subject to high variability year to year, required no complex modelling and could be updated annually, allowing governments to regularly review their pledges to reduce greenhouse gas emissions.

The paper said the index was a simple way to ensure consistency between changes in climate, individual countries' pledges, and the overall goal of reducing emissions.

"The creation of an agreed index of global warming would be a useful tool to assist policymakers to work out where we are in terms of achieving the main aims for climate policy," Frame said in a statement Tuesday.

"As we know from inflation-targeting and other aspects of health, social and environmental policy, indexing can help governments by reducing the opportunity for diversionary arguments based on the selective use of data," he said.

"At such a crucial time for climate negotiations, this proposed index offers a way to evaluate climate policies that tackles the uncertainty of climate response, which to date has stalled progress of mitigation strategies."