On the eve of the 2016 United Nations climate summit in Marrakech, Morocco, one of the world’s leading climate consultancies is advising that a 1.5°C long-term limit on average global warming is feasible—but only if countries act quickly to drastically cut greenhouse gas emissions now, and prepare to remove carbon from the atmosphere in the second half of the century.
“A further delay in implementing stringent climate policies is something the world cannot afford,” Climate Analytics warns in an October 28 blog post. It adds that the impacts of present-day emissions “are already being felt today in vulnerable countries, and are likely to get much worse after 2050.”
The blog post reports on an October 24 meeting in Brussels where climate modellers looked at a variety of scenarios for reaching the 1.5°C long-term target embedded in the Paris Agreement, which enters into force this Friday. The gathering culminated the three-year ADVANCE Project, an effort by 14 European research institutions to develop a new generation of future climate scenarios.
“The conclusion from the ADVANCE Project conference was quite clear: to meet the long-term goal of the Paris Agreement, net emissions would need to reach zero by 2050, and then go below zero in the second half of the century,” Climate Analytics reports. “Most efforts in the short term should focus on the power sector, which should become carbon-free no later than 2050.”
After that, though, “the new scenarios deploy carbon dioxide removal (CDR) technologies in the second half of the century, to compensate for the lack of climate action in the past.” The principal option appears to be biomass with carbon capture and storage (BECCS), a strategy that some Paris conference observers declared “science fiction” in the days after they got home last December.
While Climate Analytics’ Fabio Sferra acknowledges that “those technologies…are currently available only at pilot scale,” he cites the rapid growth of renewable energy over the last decade as evidence that “policies can provide strong incentives to the private sector to deploy BECCS at large scale, which in the scenarios is phased in by the 2030s. A range of social, legal, and legislative challenges related to BECCS, however, await solutions.”
While those issues sort out, Sferra says the immediate priority is to get on with implementing the Paris deal. “Research takes time, but mitigation actions can’t wait,” he stresses. The new models developed by the ADVANCE Project show the energy sector on track to emit more than twice its available carbon budget in a 1.5°C pathway, which means some form of carbon capture will have to remove at least 500 gigatonnes from the atmosphere by the end of this century.
Sferra points to the 2018 review of countries’ Paris commitments and the upcoming IPCC special report on 1.5°C pathways as influences that will help close the gap between the long-term target and a set of national policies that are currently pushing the globe toward a 3.5°C world.