What would a heated world look like?
Going beyond the Paris Agreement and limiting global heating to 1.5 degrees Celsius
The terms “point of no return” and “1.5 degrees Celsius of warming” have been much bandied about during the press coverage of COP29, but what does this really mean in terms of what the Earth has gone through before and what it is going through now? I found an interview in the Sueddeutsche Zeitung (a South German newspaper) that shed some light on this matter, and will be translating and summarising some parts of it for this article.
The interviewed scientist is Kasia Sliwinska, a geologist and ecologist trained in Aarhus University who is affiliated with the Geological Survey of Denmark and Greenland (GEUS). Original interview can be found here
What was new about the article compared to most journalistic coverage is that Sliwinska referred to data from ice cores and sediment cores to estimate what global climate conditions were like in the far past, over millions of years ago.
This was complemented with highly visual descriptions about the altitudes at which various types of wildlife can be found, from palm trees in Antarctica and alligators in the far north during the Eocene period to sequoia trees in northern central Europe and the ancestors of elephants, flamingos, snakes, and tortoises roaming wild in much of today’s Europe during the Miocene. These all point to not just higher temperatures but also higher levels of humidity in the air, which allowed these types of wildlife to thrive. The Miocene was delved into because it most closely resembles the world that we are heading towards with 3 degrees of projected warming and some mitigation measures taken to try and store carbon underground or cut emissions, while the Eocene is much harsher and less friendly to human habitation and was based on the projection of not cutting emissions at all.
Climate change denialists sometimes bring up historic periods of cooling and heating to suggest that we don’t need to do anything about the climate now as the earth will automatically rebalance anyway. This interview addressed such perspectives as well, pointing out that the rate of increase of carbon dioxide in the atmosphere is definitely much sharper and exponential compared to natural rhythms of emissions from, say, volcanic eruptions. Also, this increase is definitely tied to human-induced causes such as industrial activity, so the effect of us as one species on the earth’s climate is not doubtable.
I particularly enjoyed this interview because it was solidly based on scientific research and essentially pointed out that the wildlife in our world will evolve and adapt no matter what the earth’s climate ends up being like, as the earth has seen hotter climate conditions before, but we as humans are the ones that may not be able to thrive in much hotter and wetter conditions. It was also not alarmist or doom-and-gloom themed in its framing of climate change despite being grounded in science, which is a breath of fresh air.
The question that remains unanswered is - will humans gather our collective intelligence to mitigate climate change sufficiently that we can continue to thrive? That is what we will be working on in the run-up to 2050 while the world tries to hit its net zero targets.