A 6 per cent fall in global carbon emissions due to less car usage and reduced flights during the Covid pandemic "was nothing to celebrate", according to the leading climate scientist Johan Rockström of Potsdam Institute for Climate Impact Research in Germany.
"It was caused for the wrong reason. We don't want to succeed on climate by destroying the economy and jobs," he told the AIB sustainability conference on Monday – part of Ireland's Climate Finance Week.
It did, however, indicate the kind of annual cut needed "until we come to zero emissions", Prof Rockström said – but current pace suggested "a rebound back to the old economy". He hoped the United Nations climate summit in Glasgow, COP26, could be a turning point.
A halving of emissions by the end of the decade was needed to ensure a soft landing for the planet on the target of curtailing temperature rise to 1.5 degrees, he added.
The world would not be going over a cliff after 2030 if that target was not met, but failure to act would increase likelihood of irreversible changes that would take centuries to turn around and include more frequent extreme weather events like those experienced during summer 2021.
If countries did not contain their carbon budgets, the global temperature increase would probably crash through two degrees, and trigger cascading effects with unknown consequences, he noted.
Earth science indicated the window was still open to meet the climate deadline though only just, but there was a question mark over geopolitical setting of the world on the correct course, which Prof Rockström believed was “a really good reason for action”.
His wish list for COP26 was a decision to end coal investment; putting “a serious price on carbon”, climate spending shifting from “billions to trillions”; fully recognising the role nature plays; and upgrading national commitments from countries so they are “aligned with science”.
If social tipping points were reached, “the 2020s will see the fastest economic transition in history”, while it was clear that the required technologies were “scaleable and economically viable”. There would be a short-term bump to recalibrate for past mistakes, in effect the planet subsidising fossil fuel exploration and greenhouse gas generation in the pursuit of cheap food and energy, Prof Rockström predicted.
The global food system was the single largest cause of the ecological and climate crises; so agriculture had to become a carbon sink including a curtailing of cereal-fed, intensive livestock production. He was not advocating everyone become vegans, but favoured a better balanced flexitarian diet.
Film-maker James Cameron said his blockbuster movie Titanic was a metaphor for hubris and human capacity for denial, that could easily be applied to to the climate issue, in that "We are in that 90 seconds of seeing the iceberg and now trying to turn the ship".
There were those who just wanted business as usual, when “We have to change how we do business, how we eat, how we conduct our lives”, he insisted. “Time is not on our side . . . People regarded as extremist have probably understated what is facing the world.”