Study Shows Need for Action Against Climate Crisis
The topic of when human society will be affected by rising average temperatures and changes to the planet, and when planetary boundaries will be crossed, is being discussed in science and politics. This will also be addressed at the UN Climate Conference (COP30) starting on November 10 in Belem, Brazil.
Climate Crisis: When Does the Good Life End?
In the journal "Nature Climate Change," a group led by Thomas Gasser from the Université Paris-Saclay and the International Institute for Applied Systems Analysis (IIASA) in Laxenburg near Vienna has set out to provide a new contribution to this topic. Ultimately, it is about estimating as accurately as possible when the negative impact of humans on important Earth systems becomes too great to still allow humanity a good life. The research team examined this considering four aspects: global warming, ocean acidification, the rate of sea level rise, and the melting of Arctic sea ice.
Regarding warming, it was assumed that an increase of 1.5 or at most two degrees Celsius above pre-industrial levels can still be considered somewhat manageable. This is also related to avoiding the complete disappearance of sea ice in the north, most likely when a global temperature increase of around 1.7 degrees is reached. For ocean acidification, a decrease in pH value by 0.2 points on the scale compared to pre-industrial times should be avoided, and regarding sea level rise, an increase of more than five centimeters per decade should be avoided, the scientists write in their work.
"Several Million Possible Futures"
Considering these four factors and under various assumptions about the timing of the peak of CO2 emissions, reaching "net-zero," CO2 removal from the atmosphere, and however technically realized solar radiation reduction, the researchers arrived at a multitude of different climate paths or "several million possible futures," as they put it. Central result: With at least around 80 percent probability, the global average temperature increase would remain below two degrees Celsius if emissions peak in 2030, followed by a global net-zero CO2 balance in 2050, and the capacity for technical CO2 removal from the atmosphere increases to ten gigatons per year. The chance that under this very optimistic assumption all four boundaries are not exceeded simultaneously is only about 35 percent, it further states.
The Clock is Ticking
Without significant CO2 removal through technical solutions or massive reforestation in the future, the total emissions would need to be significantly reduced starting this year to remain below a temperature increase of two degrees with at least a low probability. Without CO2 capture, according to the calculations, the greenhouse gas budgets will be exhausted very soon. Implementing highly speculative, extremely controversial, and technically and ethically questionable approaches to controlling solar radiation on Earth could slightly improve the chances of adhering to the planetary boundaries examined here. However, this would have no impact on ocean acidification, as it only depends on atmospheric CO2 concentration, emphasize the scientists, for whom the analysis shows how strongly various aspects of climate warming must be considered together.
(APA/Red)
This article has been automatically translated, read the original article here.