Yesterday, the Working Group on the Anthropocene (WGA), made up of 35 of experts from around the world proposed that a new geologocal epoch - the Athropocene - needs to be declared. The scientists made their recommendation to the International Geological Congress in Cape Town, South Africa.
The geological time of our planet is divided up into epochs. You will have no doubt have heard of Jurassic Park. Well, the Jurassic ran from 200 million years ago to around 145 million years ago and was the middle phase in the era of the dinosaurs. The last dinosaurs died out at the end of the Cretaceous period, about 65 million years ago.
Currently, we are living in the Holocene epoch (from the ancient Greek 'holos' meaning whole or entire and 'cene' meaning new). The Holocene has been a period of relatively stable global climate conditions that have existed since the end of the last Ice Age, about 12,000 years ago. But WGA's scientists argue that this stability has already ended and that we are now living in a time when humans have made such an impact on our planet that this needs to be recognised with a new geological epoch. Athropocene comes from ancient Greek words, 'anthropo' meaning human and 'cene' meaning new.
In order for a new epoch to be declared, significant changes and impacts have to be observable around the world. WGA's scientists propose that the Athropocene should begin around 1950. This was when nuclear weapons testing led to radioactive elements settling on our planet's surface as they gradually drifted down to earth having been blasted into the stratosphere. Also since the 1950s, carbon dixode emissions caused by human activities have increased markedly, sea levels have risen and many species have become extinct.
But other signals of a new epoch include plastic pollution, increased nitrate and phosphate levels in soils as a result of the use of artificial fertilisers, or even the rise of the chicken as the world's most common bird. As a result of their being bred for food production, chickens are now much bigger than they were before World War Two and will make up a significant part of the proposed epoch's fossil record.
WGA's scientists will now look to find the best indicators for the start of the Anthropocene, which might be from analysis of ice cores from Greenland, the stalactites and staclmites of the Ernesto Cave in Italy, which build up a new ring of sediment every year, or even layers of rubbish in landfill sites.
It is possible that the term Anthropocene could be adopted officially within the next few years. If it is, then we are already living in the Anthropocene epoch.
Photo by Doc Searls