We have three years to turn the tide of world’s carbon dioxide emissions, warn a coalition of scientists and leaders in a comment piece in Nature this week. Writing ahead of the G20 summit in Hamburg on 7–8 July, Christiana Figueres, former head of the United Nations Framework Convention on Climate Change, with colleagues that include Lancaster University’s Professor Gail Whiteman, set out six urgent milestones for turning around the world’s carbon emissions by 2020, “before it is too late”.

The authors are optimistic that there is enough momentum for the global transition to a low-carbon economy to be inevitable, despite headwinds such as President Donald Trump’s announcement that the United States will pull out of the Paris climate agreement. In the past three years, global emissions of carbon dioxide from the burning of fossil fuels have levelled after rising for decades, an encouraging sign that policies and investments in climate mitigation are paying off. However, the pace needs to be quickened. “When it comes to climate, timing is everything,” the authors explain. Should annual emissions continue to rise beyond 2020, or even remain level, the temperature targets set in Paris become almost unattainable.

Professor Whiteman adds: “Climate science underlines the unavoidable urgency of our challenge.  But equally important is the fact that the economic, technical and social analyses show that we can resoundingly rise to the challenge through collective action.  We can do this.  We must do this.  And the momentum shows that we are.”

The comment piece identifies milestones for 2020 in six sectors — energy, infrastructure, transport, land use, industry and finance — in which significant breakthroughs on emissions reductions could be achieved quickly. They call on global leaders at the G20 summit to recognise 2020 as a crucial year for hardening their ambitions on climate change, and support recommendations for financial institutions to build strategies towards fully decarbonizing their operations.

“Let us stay optimistic and act boldly together,” they conclude. 

#2020DontBeLate

The lead authors for the piece comprise: 
Christiana Figueres, (Mission 2020)
Hans Joachim Schellnhuber (Potsdam Institute, Germany)
Gail Whiteman (Lancaster University, UK)
Johan Rockström (Stockholm Resilience Centre, Sweden)
Anthony Hobley (Carbon Tracker, London, UK)
Stefan Rahmstorf (Potsdam Institute for Climate Impact Research, Germany)