What Ancient Climate can Teach us About our Future?

Climate change is causing infectious diseases to claim more land, crops to get more fragile to weather stresses, wildfire to become far more dangerous, putting millions of animal and plant species at risk of extinction.

This is happening now, and we can’t be sure about how things would escalate going forward.

Sometimes, if you want clues into the future, you have to look at the past. This becomes very serious when talking about the world’s climate system.

In the case of the ongoing warming of our planet, we may have to go back through time, millions of years into the past, to paint a picture of Earth’s future.

Our future.

That’s what a group of scientists did. They studied Earth’s ancient climate to reveal worrying prospects for what’s to come.

What Earth’s Ancient Climate Reveals About the Future

Using a state-of-art climate model, researchers from the University of Arizona and the University of Michigan simulated Earth’s climate as it was millions of years ago to see how it would develop in our future.

Specifically, they looked at the global warming that occurred during the Early Eocene Period, more than 50 million years ago. This was a time when the global warming climate was at a stage, about 25° F warmer than today, that reflects Earth’s future warming.

They found that an additional increase in carbon dioxide leads temperatures to rise higher than they should. In other words, the planet’s sensitivity increases with more and more CO2 in the atmosphere.

Jiang Zhu, first author of the study, can’t stress enough the “scary” aspect of their findings:

“We were surprised that the climate sensitivity increased as much as it did with increasing carbon dioxide levels. It is a scary finding because it indicates that the temperature response to an increase in carbon dioxide in the future might be larger than the response to the same increase in CO2 now. This is not good news for us.”

This is the first time scientists simulate the Early Eocene’s climate, revealing our planet’s increasing sensitivity, which didn’t show up in previous simulation attempts of that geological period.

The team managed to do this thanks to the improved representation of cloud processes in the climate model they used, CESM1.2, or the Community Earth System Model version 1.2.

Climate change affects the distribution and types of clouds, threatening to strip away the cloud cover from Earth’s atmosphere, and with it its cooling effect. In this simulation, the cloud cover reduced in density, amplifying carbon-induced warming.

So simply put, things won’t only go bad, but also at an accelerating rate!