Free Astronomy Magazine November-December 2020

27 NOVEMBER-DECEMBER 2020 ATMOSPHERIC POLLUTION A bove, the changes in CO 2 in the atmosphere over the last 800,000 years. Below, the changes in temperature since the beginning of the Cambrian, when life was es- sentially aquatic. ologist Eugene Filmore Stoermer) indicates the period within which the impact of human activity on the environment pro- duced effects that are unequivocally distin- guishable from those produced by natural phenomena and processes. The Anthro- pocene de facto overlaps a more or less ex- tensive part of the Holocene, the most recent geological epoch (the last of the Quaternary) and the one we now live in, which conventionally began about 11,700 years ago at the end of the Würm Glacia- tion. The anthropogenic (man-made) envi- ronmental changes recognizable in the Holocene have different weights depend- ing on the aspects considered. Here we are essentially interested in identifying the his- torical context in which human activity has indisputably produced widespread and persistent atmospheric pollution. There is Data: Luthi, D., et al.. 2008; Etheridge, D.M., et al. 2010; Vostok ice core data/J.R. Petit et al.; NOAA Mauna Loa CO2 record. Carolyn W. Snyder