== Add comparison shown in Scientific American's article The Last Great Global Warming by Lee R. Kump  June 29, 2011. == 

 Add comparison shown in Scientific American's article The Last Great Global Warming: Surprising new evidence suggests the pace of the earth's most abrupt prehistoric warm-up paled in comparison to what we face today. The episode has lessons for our future by Lee R. Kump  June 29, 2011.  Quotation example ...   References include: The Paleocene-Eocene Thermal Maximum: A Perturbation of Carbon Cycle, Climate, and Biosphere with Implications for the Future.  Francesca A. McInerney and Scott L. Wing in Annual Review of Earth and Planetary Sciences, Vol. 39, pages 489-516; May 2011.