There is no longer any doubt that we live in a world in which humans dominate ‘natural’ processes. We now regulate the atmosphere and earth’s climate through carbon dioxide emissions; control the nitrogen cycle through the use of nitrogenous fertilizers, and are the major force governing the earth’s vegetation. As recently as the early 20th century, most natural processes were indeed governed by nature, but that is no longer the case. Nature has become a wholly owned subsidiary of humanity.
In 2002, the chemist Paul Crutzen proposed that we acknowledge this reality by starting a new Epoch, the Anthropocene. The Holocene, the most recent Epoch, began 10,000 years ago (technically, it began 10,000 radiocarbon years before 1950). Crutzen felt that humans now so dominate natural processes that it was appropriate to use the new term. The term has been widely accepted as an informal description of current conditions.
Jan Zalasiewicz and other members of the Stratigraphy Commission of the Geologic Society of London, writing in GSA Today, have now proposed that geologists and other scientists formally accept the term Anthropocene. Geologists are particularly interested in processes that alter stratigraphy, the orderly deposition of sediments other rock-forming materials. Since humans have dramatically increased erosion, there is now a distinct stratigraphic signal of human influence. Changes in the carbon cycle and global temperatures, alterations of the world biota, and ocean level and chemistry are additional human-influenced factors that are changing stratigraphy.
Zalasiewicz proposes that 1800 be considered the year in which the Anthropocene began. This is an arbitrary date but has the advantage of occurring before or at the very beginning of global human influences on natural processes.
The Anthropocene, an informal designation for the last few years, is now in the process of becoming official. It is a useful term, especially in teaching, that helps clarify that the earth is indeed a human-dominated place.
