Ninety million years ago, the Earth was warmer than it is today. We might go to a similar world in the next few centuries, but we’re not there yet. I recently saw an article on what that meant for Antarctica. I was surprised.
Contrary to the north pole, which is just ice covering ocean, the south pole is in fact a landmass. This land is completely covered in ice, and mostly a very inhospitable place. Being near the south pole, it’s day-night cycle is screwed in both summer and winter, with months-long days and nights. Then there’s the cold.
Temperatures can drop deep below zero, with a record of -89.2 degrees Celsius set in 1983. In summer, at the coast, the temperature can reach slightly better values of 5 to 15 degrees, but skinny dipping is definitely out.
The reason for this extreme cold is that the south pole has land, not ocean beneath it. An ocean is relatively warm, while land is not. Also, Antarctica is above sea level, several kilometers above it, in fact.
Antarctica is also a desert. It snows, but only a very little. Of course, contrary to a desert, what rains down just piles up over time. So, a very cold desert, but a desert nonetheless.
Basically, we’re talking about a frozen wasteland. It does have some penguins and whales, which is something, but most of it is not a place you’d want to be.
Antarctica That Was
Ninety million years ago, things were different. The amount of carbon-dioxide in the atmosphere was much higher. There were no icecaps, and sea levels were roughly 170 meters higher than at present. Antarctica, at the time, had a moderate climate, much like present day Germany. The average temperature was about twelve degrees Celsius, with summers reaching twenty degrees or more.
The result was that rain forests covered antarctica. Yes, the freezing hell that is antarctica now was covered in rain forest ninety million years ago. Mind you, the continent hasn’t moved very much since then, meaning it was warm there, but it still featured a four-month night in winter and a four-month day in summer.
Ninety million years ago was also the time of dinosaurs. Sixty million ago, a five-to-fifteen-kilometer wide rock smashed into Yucatan and wiped almost all of them out, but that was still a distant thirty million years off when Antarctica was forested. From finds in Australia, which was the last continent to drift away from Antarctica, we have some idea of what the dinosaurs would have looked like. An example is below.
It is interesting to wonder what fossils still lie below the arctic ice. Of course, we can’t reach them now, but perhaps, someday.
The cold came
About 40 million years ago, Australia separated from Antarctica. CO2 levels had already dropped since the days of the rain forest. The continents drifted apart more, creating the circumpolar current. This means no warm water came down to Antarctica from further north, and with the fall of the CO2 levels, Antarctica froze over. For the last fifteen million years, so since long before the first human appeared on Earth, the continent has been completely covered in ice.
Scientists as far back as ancient Greek times have theorized the existence of the continent, but only in the last few hundred years have ships come close to it. The first human sighting of land was less than two hundred years ago.
I find the notion of dinosaurs and rain forests in Antarctica fascinating. I can already think of a dozen ways to incorporate this into stories. Maybe I will actually get around to writing those stories some day.
Until then, we can fantasize about the forested continent that was.