Over the past 70 years, humanity has finally surpassed other geological forces as the planet's dominant force. The main witness is currently thought to be a lone lake in Canada.
 |
| Crawford Lake from Google Maps |
Lake Crawford was just 240 meters long and 120 meters broad, but it was already well-known. The little Canadian body of water is frequented by school groups from all over the country during the week and weekend day visitors from all over the world. It is located 50 kilometers southwest of Toronto.
You may learn which animal species are endangered in the area by taking a stilt walk around the lake. Three longhouses and an indigenous garden, which depict how the Iroquois in the area once lived, are the major draws.
But as of this Tuesday night, Lake Crawford has gained not just national but also international notoriety. It is meant to serve as a scientific benchmark for the Anthropocene, a new period on earth called for human impact on the planet. Now, this has received the support of the Anthropocene Working Group (AWG), a 35-person organization made up primarily of geologists.
Whatever falls from above - the pollen from crops, the fly ash from coal combustion, the plutonium from atomic bomb tests, the nitrogen from industrial agriculture - is covered with a thin layer of calcite every summer due to the special water chemistry and is thus preserved. This unique scientific archive has been forming at a depth of 24 meters on the bottom of the lake for centuries and millennia. According to Brock University geologist Francine McCarthy, who has extensively investigated Lake Crawford, "the sediments allow us to reconstruct the human impact on this site with maximum resolution."
These unique qualities of the lake should now aid in defining the Anthropocene and persuading the top geological organizations to formally declare the new epoch.
For the International Commission on Stratigraphy (ICS), which oversees the division of geological ages and epochs, the group has been looking into whether or not humans have truly altered the earth to such an extent that the Holocene and the Anthropocene have come to an end since 2009. This notion was first offered in 2000 by the Mainz-based atmospheric scientist and Nobel Prize winner Paul Crutzen.
The group's response is unmistakable: "The earth has not only reached a completely new state as a result of climate change, but also as a result of a large number of interacting factors, which is fundamentally different from the entire history of the earth to date," says stratigrapher Jan Zalasiewicz, who works at the ICS and is in charge of the earth's history since the start of the last ice age 2.6 million years ago. He uses as examples the extinction of species, the spread of man-made products like concrete and plastic throughout the world, and radioactive fallout from atomic bomb blasts.
The AWG's director, British geologist Colin Waters, asserts that there is no turning back to the Holocene and notes that 50,000–100,000 more years of expected human-caused global warming.
But there was still a crucial component that needed to be included to the group's plan for the new earth era. Geology needs reference points that represent the major periods of earth's history, much as the original meter and kilo used to be the units of measurement for everything and specific animal and plant specimens in natural history museums serve as the standard for describing species.
Source:The Washington Post/FAZ