If you think it’s warm now, you should have been here around 52 million years ago. Back then you could have basked beneath palm trees on the coast of Antarctica in an area that’s now under about 1.9 to 2.5 miles (3 to 4 kilometers) of ice.
Rock samples obtained from the seabed off the coast of Wilkes Land, Antarctica were found to contain fossil pollen and spores that included palm pollen and another type of pollen from trees related to today’s baobab trees. They also found evidence of bacteria which would have lived in the soils along the Antarctic coast at the time. They concluded that average temperatures at the time were about 68 degrees Fahrenheit or roughly 20 degrees Celsius. Although they believe that the interior was somewhat colder due to higher elevations and would have been populated with the ancesstors of trees that can be found today in places like New Zealand.
Some climatologists concluded that this warming period, which lasted roughly from 53 to 46 million years ago, was likely caused by high levels of carbon dioxide in the atmosphere. They estimate that concentrations at the time ranged somewhere between 990 to a few thousand parts per million compared with today’s carbon dioxide level, which is estimated at about 395 ppm. If the warming effects of high carbon dioxide levels are a primary cause of global warming, the earth was much warmer at that time than it is today.
There is an interesting concept here. Human beings weren’t around 53 million years ago to burn fossil fuels, which is currently thought to be behind the current rise in carbon dioxide levels. Therefore, it seems logical that some other mechanism besides man may be at fault. Throughout this planet’s history, there have been both glacial and interglacial periods. Some of the interglacial periods were in fact generally much warmer than those we are experiencing now. And it is likely that local weather conditions during those times were as severe and threatening as those being faced in much of the world today. What does that mean for mankind? Climatologists are still divided, of course. As for the rest of us, it seems that the only thing we can do is wait and see.
There are two interesting articles about the Antarctica findings and their possible significance to climate change. One is here, the other is here.
If you’re interested in finding out about other natural forces that can cause climate change, visit here