Date:1 August 2011
The mass extinction of marine life in our oceans during prehistoric times is a warning that the Earth will see such an extinction again because of high levels of greenhouse gases, according to new research by geologists.
Professor Martin Kennedy of the University of Adelaide and Professor Thomas Wagner of Newcastle University have been studying “greenhouse oceans” – oceans that have been depleted of oxygen and suffered from increases in carbon dioxide and temperature.
Says Kennedy: “Our research points to a mass mortality in the oceans at a time when the Earth was going through a greenhouse effect, with high levels of carbon dioxide in the atmosphere, and rising temperatures, leading to a severe lack of oxygen (hypoxia) in the water that marine animals are dependent on.
“What’s alarming to us as scientists is that there were only very slight natural changes that resulted in the onset of hypoxia in the deep ocean. This occurred relatively rapidly – in periods of hundreds of years, or possibly even less – not gradually over longer, geological time scales.
“If you consider that the amount of carbon dioxide in our atmosphere could double over the next 50 years, this will be like hitting our ecosystem with a sledgehammer…"
Source: University of Adelaide