Frozen wasteland is the word that comes to our brain when we think about the poles of our Earth. For a very long time, these have remained ice lands. Even though there’s a fair possibility for life to exist here, there are good reasons why humans and most other animals cling to the safety of more hospitable climates closer to the equator.
From our planet’s ancient history we know that these lands were not frozen wastelands. Around the mid-Cretaceous period.e, about 90 million years ago highly dense concentrations of CO2 could have created hotter temperatures that led to the melting of polar ice sheets and which as a result paved a way to sending sea levels soaring to up to 170 meters (558 feet) higher than they are today.
Wondering what the South Pole looked like then? Then here’s your answer.
An expedition aboard the RV Polarstern in the Amundsen Sea took place in 2017. Researchers drilled deep into the ground underneath the seabed of West Antarctica, close to the location of the Pine Island and Thwaites glaciers, and only about 900 kilometers (560 miles) away from the South Pole.
At depths about 30 meters, they found out which contrasted with the sediment composition resting closer to the surface.
“The first analyses showed that, at a depth of 27 to 30 meters (88 to 98 ft) below the ocean floor, we had found a layer originally formed on land, not in the ocean.” said geologist Johann Klages from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research in Germany.
Nobody had ever pulled a Cretaceous Period sample out of the ground from such a southern point on the globe. The researchers can’t have been prepared for what closer examination with X-ray computed tomography (CT) scans would reveal.
The scans reveal an intricate network of fossilized plant roots. The microscopic analysis also showed evidence of pollen and spores, all pointing to the preserved remains of an ancient rainforest that existed in Antarctica approximately 90 million years ago, eons before the landscape was transformed into a barren province of ice.
“The numerous plant remains to show that the coast of West Antarctica was, back then, a dense temperate, swampy forest, similar to the forests found in New Zealand today,” says palaeoecologist Ulrich Salzmann from Northumbria University in the UK.
These not only tell us that polar plant life existed way back when they also give us an idea about how such a thing could have been possible.
To figure how could this ancient rainforest thrive in such an environment of being deprived of the sun for so long, researchers used modeling to reconstruct what the ancient climate of this long-gone forest region might have been like, based on biological and geochemical data in the soil sample.
In this super-heated environment (with an annual average air temperature of around 12 degrees Celsius or 54 degrees Fahrenheit in the Antarctic), dense vegetation would have covered the entire Antarctic continent, and the ice sheets we know today–along with their associated cooling effects–would have been non-existent.
There’s a lot to find, but this provides researchers a far greater understanding of the deep ties between CO2 concentration and polar climates in prehistoric times when dinosaurs still roamed the Earth.
We are in an interesting time because if we continue what we’re doing right now, then it could lead to something that we can’t control anymore.
The findings are reported in Nature.