Scientists say the Anthropocene epoch began in the 1950s: What it means, significance

• According to geologists, sediments at Crawford Lake in Canada’s Ontario have provided evidence of the beginning of the Anthropocene epoch, a major development that could change the Earth’s official geological timeline

Anthropocene epoch

• The Anthropocene epoch as a term was first coined by Nobel Prize-winning chemist Paul Crutzen and biology professor Eugene Stoermer in 2000
• It was used to denote the present geological time interval, in which the Earth’s ecosystem has gone through radical changes due to human impact, especially since the onset of the Industrial Revolution.
• There are numerous phenomena associated with this epoch
  • like global warming, sea-level rise, ocean acidification, mass-scale soil erosion, the advent of deadly heat waves, deterioration of the biosphere and other detrimental changes in the environment.
  • Many of these changes will persist for millennia or longer
  • They are altering the trajectory of the Earth System, some with permanent effect.
• They are being reflected in a distinctive body of geological strata now accumulating, with potential to be preserved into the far future

Key Findings

• The new epoch started sometime between 1950 and 1954.
• The data show a clear shift from the mid-20th century
• It takes the Earth’s system beyond the normal bounds of the Holocene (epoch that started at the end of the last ice age 11,700 years ago)
• Not every geologist agrees that the Anthropocene epoch is a reality
  • There are disagreements regarding when it began, or has it already begun, or if they have enough evidence to prove its advent.
• There are distinct and multiple signals starting around 1950 in the water body, which show that “the effects of humans overwhelm the Earth system”
• The “presence of plutonium (due to detonation of nuclear weapons) gives a stark indicator of when humanity became such a dominant force that it could leave a unique global ‘fingerprint’ on our planet.”
• But these findings don’t prove the advent of the Anthropocene epoch.

How is the Earth’s geological time divided?

• The planet’s geological time scale is divided into five broad categories viz. eons, eras, periods, epochs and ages.
• While eon is the broadest category of geological time, age is the smallest category.
• Each of these categories is further divided into sub-categories.
  • For instance, Earth’s history is characterised by four eons, including Hadeon (oldest), Archean, Proterozoic, and Phanerozoic (youngest).
• Most of the boundaries on the geological time scale correspond to the origination or extinction of particular kinds of fossils.
  • This is also related to something called the principle of faunal succession
  • It states that different kinds of fossils characterise different intervals of time.
• As of now, at least officially, we’re in the Phanerozoic eon, Cenozoic era, Quaternary period, Holocene epoch and the Meghalayan age.