Research has given new clues to understanding the Palaeocene-Eocene Thermal Maximum (PETM), a catastrophic world-warming event that took place 56 million years ago. The data shows the mysterious rise of atmospheric carbon took place over a relatively short period of time, killing huge swaths of marine organisms in the process. Now, according to an alarming story in the Washington Post, modern civilization is pumping out carbon at 10 times that rate.
A study published in Nature Geoscience examined findings from a coastal New Jersey core of deep sea sediment from the time of the PETM. As Chris Mooney of The Washington Post explains, scientists have yet to come to a consensus as to what caused the event, but it is clear that a stark rise in carbon dioxide caused Earth to warm rapidly – climbing 5 degrees Celsius higher than normal – and the oceans to become acidic.
The study revealed that about 1 billion tons of carbon were being emitted into the atmosphere per year during that time, totaling between 2,000 to 4,500 tons over a span of 4,000 years. Today, however, we are producing 10 billion tons annually – yes, ten times more than millions of years ago.
Our current rate of destruction far surpasses the devastating PETM, which led to a major warming period of 100,000 years. The study’s authors write, “Given that the current rate of carbon release is unprecedented throughout the Cenozoic, we have effectively entered an era of a no-analogue state, which represents a fundamental challenge to constraining future climate projections.” In other words, the impact of manmade climate change is unheard of in observable Earth history, which will make it much harder to foresee what is coming our way.