
Ancient Wyoming forests took 100,000 years to rebound from PETM-like warming
A Wyoming fossil study shows forests during the Paleocene–Eocene Thermal Maximum lost about 60% of their canopy as temperatures spiked, with canopy recovery taking over 100,000 years. By analyzing fossil leaf cuticles and soils, researchers linked leaf cell shape to canopy density, revealing how forest structure controlled light, temperature, water flow, and carbon storage. The finding is a cautionary tale for today: higher CO2 can boost growth only within the trees’ temperature and moisture limits, and rapid modern warming may push forests beyond thresholds that require millennia to recover.












