Study Finds Wyoming Forests Lost 60% Canopy, Took 100,000 Years to Recover
Updated
Updated · The Conversation · Aug 13
Study Finds Wyoming Forests Lost 60% Canopy, Took 100,000 Years to Recover
2 articles · Updated · The Conversation · Aug 13
Summary
A new Science study found southern Wyoming forests lost about 60% of their canopy during the Paleocene-Eocene Thermal Maximum 56 million years ago and did not fully recover for well over 100,000 years.
Up to 11 degrees Fahrenheit of warming drove heat and drought stress that killed trees, opening dense canopies, favoring ferns and later palms, and reshaping how water and sediment moved through the basin.
Researchers reconstructed the ancient forests from microscopic leaf cuticles, linking the shape of thousands of fossil epidermal cells to canopy density using modern forest samples from Central and South America.
The study says the forests entered the warming episode at peak density rather than in decline, suggesting rising carbon dioxide initially boosted growth before heat and water limits overwhelmed that benefit.
Because humans are releasing carbon dioxide about 10 times faster than natural processes did then, the authors say the fossil record warns modern forests could cross similar thresholds on a much shorter timetable.