Geological epochs are units of time defined by stratigraphic layers that are chemically or biologically distinct and are officially recognized by International commission on stratigraphy.
The Holocene (meaning ‘recent whole’) marks the period since the last ice age. It includes the current period of human expansion, agricultural advances, and more recently some major changes to the earth’s surface, biota and climate.
A range of human-induced changes suggests that the Earth has transitioned from present Holocene to whole new geological epoch, Anthropocene.
“Anthropocene”—from anthropo, for “man,” and cene, for “new” has been named so because human-kind has caused mass extinctions of plant and animal species, polluted the oceans and altered the atmosphere, among other lasting impacts.
But exact date is yet to be arrived to define the beginning of this epoch.
Reasons of acceleration:-
- Level of CO2 in the atmosphere has shot up from 280 ppm at the start of the Industrial Revolution to 413 ppm today. As a result, the average surface temperature over these two centuries has gone up by 1.5 degrees Centigrade. This has also started melting glaciers and raised the sea level by 3.2 mm every year.
- Added to the warming of the oceans and landmass caused by the Greenhouse gases (CO2, NO, Ozone, methane…), are the plastics and their debris, strewn all across the world and its oceans.
- increase in human population from 1.2 billion in 1850 to the current 7 billion, has led to massive destruction of forests and animals therein has led to a crowding problem, and its associated effects.
Significance:
- It highlights the scale of human impact on Earth and means that impact is irreversible too.
- It helps reexamine the relationship between humans & nature.
Changing climate isn’t unique to Anthropocene. But human evolution through all these evolutionary epochs was simultaneously paralleled with number of traits that allowed living organisms adapt to different environmental conditions. With growing awareness on how human actions impact the world, collective solutions have to be developed for the present epoch, Anthropocene.
