Anthropocene

The Anthropocene is a proposed epoch dating from the commencement of significant human impact on Earth's geology and ecosystems, including, but not limited to, anthropogenic climate change. As of June 2019, neither the International Commission on Stratigraphy (ICS) nor the International Union of Geological Sciences (IUGS) has yet to officially approve the term as a recognized subdivision of geologic time, although the Anthropocene Working Group (AWG) of the Subcommission on Quaternary Stratigraphy (SQS) of the International Commission on Stratigraphy (ICS), voted to proceed towards a formal golden spike (GSSP) proposal to define the Anthropocene epoch in the Geologic time scale and presented the recommendation to the International Geological Congress on 29 August 2016. On 21 May 2019, the 34 member AWG voted in favour of making a formal proposal to the ICS. Various start dates for the Anthropocene have been proposed, corresponding with the Holocene calendar and ranging from the beginning of the Agricultural Revolution 12,000–15,000 years ago, to as recent as the 1960s. As of June 2019, the ratification process continues and thus a date remains to be decided definitively, but the Trinity test of 1945 has been more favoured than others. In May 2019, the AWG voted for a starting date in the mid 20th century, but the final decision will not be made before 2021. The most recent period of the Anthropocene has been referred to by several authors as the Great Acceleration during which the socioeconomic and earth system trends are increasing dramatically, especially after the Second World War. For instance, the Geological Society termed the year 1945 as The Great Acceleration. An early concept for the Anthropocene was the Noosphere by Vladimir Vernadsky, who in 1938 wrote of 'scientific thought as a geological force.' Scientists in the Soviet Union appear to have used the term 'anthropocene' as early as the 1960s to refer to the Quaternary, the most recent geological period. Ecologist Eugene F. Stoermer subsequently used 'anthropocene' with a different sense in the 1980s and the term was widely popularized in 2000 by atmospheric chemist Paul J. Crutzen, who regards the influence of human behavior on Earth's atmosphere in recent centuries as so significant as to constitute a new geological epoch. In 2008, the Stratigraphy Commission of the Geological Society of London considered a proposal to make the Anthropocene a formal unit of geological epoch divisions. A majority of the commission decided the proposal had merit and should be examined further. Independent working groups of scientists from various geological societies have begun to determine whether the Anthropocene will be formally accepted into the Geological Time Scale. The term 'anthropocene' is informally used in scientific contexts. The Geological Society of America entitled its 2011 annual meeting: Archean to Anthropocene: The past is the key to the future. The new epoch has no agreed start-date, but one proposal, based on atmospheric evidence, is to fix the start with the Industrial Revolution ca. 1780, with the invention of the steam engine. Other scientists link the new term to earlier events, such as the rise of agriculture and the Neolithic Revolution (around 12,000 years BP). Evidence of relative human impact – such as the growing human influence on land use, ecosystems, biodiversity, and species extinction – is substantial; scientists think that human impact has significantly changed (or halted) the growth of biodiversity. Those arguing for earlier dates posit that the proposed Anthropocene may have begun as early as 14,000–15,000 years before present, based on geologic evidence; this has led other scientists to suggest that 'the onset of the Anthropocene should be extended back many thousand years';:1 this would be essentially synonymous with the current term, Holocene. In January 2015, 26 of the 38 members of the International Anthropocene Working Group published a paper suggesting the Trinity test on 16 July 1945 as the starting point of the proposed new epoch. However, a significant minority supports one of several alternative dates. A March 2015 report suggested either 1610 or 1964 as the beginning of Anthropocene. Other scholars point to the diachronous character of the physical strata of the Anthropocene, arguing that onset and impact are spread out over time, not reducible to a single instant or date of start.