Tuesday, January 25, 2011

Coal was responsible for the biggest extinction in Earth's history

The biggest extinction in our planet history hasn't occurred 65 millions years ago when big meteorite ended the age of dinosaurs, in fact the biggest extinction event in our history happened some 250 millions years ago when around 95 percent of species were wiped out in the sea and 70 percent on land. And the main culprit for this is not some big meteorite but coal.

250 millions years ago was a time when much of the land mass was gathered into one supercontinent called Pangaea, and this was the time when four-limbed vertebrates were becoming more diverse and among them were primitive amphibians, early reptiles and synapsids, the group that would eventually include currently dominant mammals.

The scientists at the University of Calgary are convinced that the main reason behind this mass extinction event were massive volcanic eruptions that burnt significant volumes of coal, producing coal ash clouds that had broad impact on global oceans.

Massive coal combustion resulting from these monster volcanic eruptions has created enormous amount of greenhouse gases, and highly toxic coal ash was released in land and water. The planet was already heating up, and coal combustion only made the situation worse, and eventually oceans were starting to suffocate because there wasn't enough oxygen which explains the loss of 95% species in oceans.

Dr. Steve Grasby, the leader of the research team said that "our research is the first to show direct evidence that massive volcanic eruptions, the largest the world has ever witnessed caused massive coal combustion thus supporting models for significant generation of greenhouse gases at this time".

The researchers discovered layers of coal ash in rocks from the extinction boundary in Canada's High Arctic like that produced by modern coal burning power plants which is direct evidence that supports this theory about the biggest extinction event on our planet.