Models show global warming could be limited to 1.5 degrees Celsius

The different models consider a variety of political, socioeconomic and technological factors, including the impacts of economic inequality, energy demand and regional cooperation. The models considered five different so-called Shared Socioeconomic Pathways, or SSPs.

"A critical value of the paper is the use of the SSPs, which has helped to systematically explore conditions under which such extreme low targets might become attainable," Keywan Riahi, energy program director at the International Institute for Applied Systems Analysis in Austria, said in a news release.

All successful scenarios involved a significant shift away from carbon fuel sources toward low-carbon energy sources. The models suggest a reduced energy demand must also be an important part of any successful SPS. The simulations also showed sustainable development strategies could play an important role in limiting climate change.

The most apparent obstacles to a workable SPS included: socioeconomic inequalities, an ongoing reliance on fossil fuels and poor public policies.

"Fragmentation and pronounced inequalities will likely come hand-in-hand with low levels of innovation and productivity, and thus may push the 1.5 degrees Celsius target out of reach," Riahi said.

In the successful scenarios, a rapidly increasing reliance on renewable energy sources allow carbon emissions to peak and begin to decline by mid-century. In the same scenarios, more energy-efficient homes and vehicles help to diminish energy demands.

Scientists suggest none of the models will be possible without a serious effort by world leaders and public policy makers.

"The study provides decision makers and the public with key information about some of the enabling conditions to achieve such stringent levels of climate protection," said IIASA researcher Joeri Rogelj.

Researchers published their findings in the journal Nature Climate Change.