The next three years will determine whether human action can avert the worst effects of climate change, according to a letter this week in the journal Nature organized by ex-UN climate secretary Christiana Figueres and Hans Joachim Schellnhuber of the Intergovernmental Panel on Climate Change.
“We stand at the doorway of being able to bend the emissions curve downwards by 2020, as science demands, in protection of the UN sustainable development goals, and in particular the eradication of extreme poverty,” Figueres told media. “This monumental challenge coincides with an unprecedented openness to self-challenge on the part of sub-national governments inside the U.S., governments at all levels outside the U.S., and of the private sector in general. The opportunity given to us over the next three years is unique in history.”
“The maths is brutally clear,” added Schellnhuber, director of the Potsdam Institute for Climate Impact Research. “While the world can’t be healed within the next few years, it may be fatally wounded by negligence [before] 2020.”
While global warming has sped up in recent months, and the last three years have been the hottest on record, the letter points to the stabilization of greenhouse gas emissions over that period as a source of hope. But the authors stress “that the next three years will be crucial,” The Guardian reports. “They calculate that if emissions can be brought permanently lower by 2020, then the temperature thresholds leading to runaway, irreversible climate change will not be breached.”
With renewable energy use on the rise, coal in decline, and the world’s governments rallying around the Paris agreement in response to the Trump administration’s withdrawal from the landmark global deal, the letter calls for G20 leaders to adopt six goals at their meeting in Hamburg July 7-8. The list includes a 30% renewable energy target for 2020, plans for major cities and states to decarbonize by 2050, shifting 15% of auto sales to electric vehicles, sectoral reform in land use, agriculture, heavy industry, and finance, and green growth.
“As before Paris, we must remember that impossible is not a fact, it’s an attitude,” the letter states.