Governments will need authoritative scientific analysis if they hope to boost their future climate change targets, the head of the Intergovernmental Panel on Climate Change said.

In an interview with ClimateWire, Chairman Hoesung Lee said the pledges that countries have made up to 2030 at the U.N. climate negotiations in Paris will not, by themselves, avoid severe climate change.

More ambition would be needed, post-2030, to ensure temperature rise in 2100 remains below 2 degrees Celsius.

He spoke from the sidelines of the Paris negotiations.

Whether the IPCC will play a role in providing this analysis will be decided by member nations. Typically, governments produce a wish list of topics for the IPCC to address in a comprehensive report on the state of the science released every five to seven years.

As chairman of the IPCC, Lee holds one of the most powerful posts in climate science. He has the ear of governments and some freedom to set the course of the IPCC (ClimateWire, Oct. 7).

Lee is a South Korean economist who specialized in natural resources and environment. In 1988, when the IPCC was created, Lee was heading a government-affiliated research institute that was helping the government craft a long-term energy policy.

“The climate change problem is deeply involved in the question of how the energy system works and how it will develop,” Lee said. “That is the way I got involved in the climate change analysis and policy.”

He began contributing to the IPCC in 1992. The organization has long been a lightning rod for controversy and a favored target of doubters of mainstream climate science. Lee said he is unfazed by the challenge.

“I’m not concerned about that at all,” he said. “What matters from now on is how can we develop solutions for climate change problems, and that will be the focus of IPCC’s upcoming assessment cycle.”

Finding a way to ‘ratchet up’ initial targets
At present, nations’ pledges, or intended nationally determined contributions (INDCs), proposed in Paris would limit temperature rise in 2100 to around 2.7 degrees Celsius, according to the United Nations.

“Obviously, [the pledges] they are not sufficient by themselves, but no one expected them to be at this stage,” Lee said. “The important thing is that they put us on the path to even lower emissions.”

That makes the ambition of nations post-2030 even more important.

“The parties are considering revisions to the submitted INDCs,” Lee said. “So I think we will have a mechanism to ratchet up the initial submissions.”

If decisionmakers make use of the IPCC’s assessment report, there “will be a very successful agreement and decisions,” he said.

So far, policymakers have ignored one of the major policy-relevant findings—the carbon budget—in the latest IPCC report. The IPCC found that nations can emit a cumulative 1,000 gigatons of CO2 to likely meet the goal of limiting temperature rise to 2 C at the end of the century. By 2011, nations had already emitted 515 gigatons.

The carbon budget is a “fairly new” idea, which may be the reason it hasn’t been used, Lee said.

“I think it will take time for policymakers to absorb the core concept of the carbon budget,” he said.

Addressing ethical questions in climate science
Some island nations at risk of being submerged by the oceans have suggested that nations should limit temperature rise even further to 1.5 C. Lee said that such revisions should be based on robust scientific assessment.

“The [2 C] stabilization goal was a politically agreed goal, based upon rigorous robust scientific assessment,” he said. “Same analysis should be applied to the question of [a 1.5 C] goal.”

To achieve their goals, nations have to deploy technologies at a much faster speed and do research and development to improve available technologies, he said. All options that could help achieve the targets, including renewables and nuclear energy should be considered, he said.

Developing nations, particularly India, have highlighted their right to develop as a matter of “climate justice.” India’s negotiations have opposed a call for decarbonization by the end of the century.

Lee said that the IPCC recruited a philosopher to address these ethical questions in the previous assessment. He said that more social scientists and economists should contribute to future IPCC assessments.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC., 202-628-6500