Paris climate targets can be met without geoengineering — provided governments act now

26 June 2018, by Darry Khajehpour, Open University, and CEN

Photo: UHH/CEN/ T.Wasilewski

A new study conducted by scientists at the UK-based Open University with participation of Universität Hamburg’s Center for Earth System Research and Sustainability (CEN) reveals: The goal of limiting the increase in average global temperatures to well below 2º C, as set forth in the 2015 Paris Climate Agreement, is within reach—provided governments act now.

Today, the research led by Dr. Philip Holden, Lecturer in Earth System Science, was published in Nature Climate Change. Aiming to show that the target agreed in Paris can still be achieved, the team of international researchers combined climate, economic, and technology models.

“We presumed, however, that past 2017 human-induced carbon emissions would not exceed a further 300 megatons max,” says meteorologist Dr. Frank Lunkeit from the CEN in Hamburg. “But this can only be accomplished if extensive political measures become effective at once—currently, about 10 megatons of carbon are emitted across the globe per annum.”

The scientists developed a three-dimensional climate-carbon cycle model and conducted numerous simulations exploring various possible climate futures. These revealed that it remains doubtful how sensitive regions, such as the Arctic and the South-East Asian monsoon area, might respond to climate change over the next 100 years.

“The regional uncertainties associated with the Paris Climate Agreement have not been explored before,” says Dr. Holden. “This is because until now, researchers have used either very simple models or models that were too complex to investigate the range of possibilities.”

Significantly, meeting the climate target does not depend on the ability and motivation of future generations to remove vast amounts of carbon from the Earth’s atmosphere through geoengineering as heavily as previously thought. Instead, the existing pace of technological change would be supported by a realistically achievable set of policies for governments, as described in a recent paper in Nature Climate Change.

The above-mentioned experts from the Open University and Universität Hamburg collaborated with colleagues from the University of California, the University of Sheffield, the University of Cambridge, the Radboud University in the Netherlands, the Max Planck Institute of Meteorology and Cambridge Econometrics.

Read the full paper: Climate-carbon cycle uncertainties and the Paris Agreement
This press release first appeared in the Newsroom of the Open University