With so many climate projections and mitigation strategies eyeing far-away years like 2050, it can be tempting to assume there’s still time to reverse the worst impacts of an ever-warming planet.
Unfortunately, that’s no longer in the cards — at least according to the United Nations Environment Programme, which just released a dismal report calling for the “world to face the inevitability of exceeding global warming of 1.5 degrees Celsius” above pre-industrial levels.
That’s significant, because the 1.5 degree threshold has long been associated with a range of grim climate tipping points at which the planet will experience irreversible consequences such as the “breakdowns of major ocean circulation systems, abrupt thawing of boreal permafrost, and collapse of tropical coral reef systems,” per a UN climate explainer.
The new UN paper, coming on the heels of the hottest summer on record and pessimistically titled “Limiting Overshoot,” identifies the consequences of this reality, and recommends some immediate actions to keep things from spiraling even further.
Though most scientists agree we’re hovering around the 1.4 degree point at the moment, the UN notes that even in the best case scenario, where “all climate commitments and policies are implemented, warming is projected to reach 1.8 degrees Celsius at a minimum.” If we follow our current track, however, the report highlights the distinct possibility of hitting 2.6 degrees by the year 2100.
That catastrophic future is far from certain, although drastic intervention is becoming increasingly urgent if we hope to stave it off. Underscoring the severity of the present moment, the UN frames the situation in terms of maintaining warming at the 1.5 degree mark — no longer a theoretical ceiling, but the new floor going forward. Doing so, the report authors write, depends “on achieving sustained net-negative CO2 emissions at global scale in the second half of this century, and potentially further reductions of non-CO2 emissions.”
“Decisions taken this decade will determine whether viable options remain to gradually reverse warming back to 1.5 degrees Celsius,” they explain.
Speaking to CBC News, UN Environment Programme executive director Inger Andersen said “let’s be very clear, 1.5 target is still the goal.”
“But now we need to approach it differently from above,” Andersen explained. “Every tenth of a degree we avoid still means less damage.”
More on climate change: It’s Official: This Is the Hottest America Has Ever Been