Scientists collected rock samples from red, purple and orange Paleocene-Eocene Thermal Maximum soil horizons in Wyoming.
Original Published Date: 
Monday, July 29, 2019

Full article issued by Pennsylvania State University.

Rock core samples from a period of warming millions of years ago indicate soils contributed to a rapid rise in atmospheric greenhouse gas and suggest modern climate models may overestimate Earth's ability to mitigate future warming, according to an ARC-funded international team of scientists.

The research team, which included ARC Future Fellowship recipient, Dr Francesca McInerney, based at the University of Adelaide, discovered a drastic drop in organic material preserved in sections of core samples from the Paleocene-Eocene Thermal Maximum, a global warming event 55.5 million years ago that's considered the best analogue for modern climate change.

The findings, according to the researchers, suggest ancient soils from a site in modern day Wyoming acted as a source of atmospheric carbon dioxide, emitting the greenhouse gas into the atmosphere, and not a sink, trapping and storing carbon underground. The implications are that global climate models, which expect soils to be a carbon sink, may overstate the ability of terrestrial ecosystems to lessen the impacts of climate change.

Photo credit: 

Image: Scientists collected rock samples from red, purple and orange Paleocene-Eocene Thermal Maximum soil horizons in Wyoming. Credit: Allison Baczynski, Penn State.