Sticking to 1.5°C would halve severe climate impacts, GDP losses in tropical countries - study
By aligning the next round of carbon cutting targets with the 1.5°C limit in the Paris Agreement, governments could halve the massive GDP losses in tropical countries and other severe climate impacts that would otherwise be expected by the end of this century under current climate action, according to a study published today in Earth System Dynamics.
Berlin – 3 August 2020 – By aligning the next round of carbon cutting targets with the 1.5°C limit in the Paris Agreement, governments could halve the massive GDP losses in tropical countries and other severe climate impacts that would otherwise be expected by the end of this century under current climate action, according to a study published today in journal Earth System Dynamics.
The new study by researchers from Climate Analytics takes governments’ current Paris Agreement climate pledges, called Nationally Determined Contributions (NDCs), and analyses the expected severity of climate impacts if they do not improve these pledges at all or if they make only incremental improvements, and compares these with a transformational, 1.5°C compatible pathway.
By incremental improvements, researchers describe a collective emissions reduction of less than 33% by 2030 compared with current NDCs. A transformational improvement, in line with the safer temperature limit, entails a 50% emissions reduction by 2030 compared with current NDCs.
The Paris Agreement requires governments to issue a new set of climate plans this year in the run up to the postponed UN climate summit in Glasgow. These plans, which are meant to be communicated every five years, should further align governments’ policies with the Agreement’s goal of holding temperature increase to well below 2°C of warming and pursuing efforts to limit it to 1.5°C by the end of this century.
Governments’ current climate plans will result in approximately 3°C of warming above pre-industrial levels, setting the world on course for severe impacts such as significant economic damage, sea-level rise and more extreme heat.
“Our study shows that if governments simply recycle their current emission reduction plans, as some have indicated, and they continue at that same slow pace until 2100, tropical countries could see around 60% reduction of their Gross Domestic Product,” said Climate Analytics’ Dr Andreas Geiges, main author of the study.
“Making the next round of climate plans compatible with the 1.5°C limit, and continuing along this trajectory, would halve this damage,” Geiges said.
Transformative emission reductions would also significantly diminish risks from other damages, such as rising seas and extreme heat.
“The level of climate inaction we see now would lock in about two metres of unstoppable sea-level rise by 2300, with ever increasing risks for generations of people living in coastal communities,” said Climate Analytics’ Dr Alexander Nauels, co-author of the study. “Transformational emissions cuts could reduce this risk by half,” Nauels said.
The study also found that under the current NDC trajectory one tenth of the global land area would experience extreme hot days more than 4°C warmer than in the recent past –another risk that would be significantly reduced by aligning climate action with the 1.5°C limit.
Incremental improvements fall short of putting the world on track to holding warming to safer levels. Even if big emitting countries such as China, the US and major economies in Europe reduced their emission levels by 33% or less by 2030, this would result in substantially greater climate impacts than a 1.5°C pathway. Also, to get the world on a 1.5°C trajectory, action by big emitting countries alone is not sufficient. All governments need to substantially cut emissions.
“Our results show that while big emitters should spearhead global efforts, transformational change to achieve the goals of the Paris Agreement needs all hands on deck,” said Dr Carl-Friedrich Schleussner, co-author of the study. “The COVID-19 pandemic requires an unprecedented reaction of governments and our results show that it is critically important that the recovery from it delivers change to address another global crisis -climate change.”
Geiges, et al. “Incremental improvements of 2030 targets insufficient to achieve the Paris Agreement goals” Earth Syst. Dynam., 11, 697–708, 2020