Soft Mountain Rock Erodes Three Times Faster Than Hard Rock, Reshaping Climate Models

A University of Massachusetts Amherst-led study reveals that weaker rock erodes three times faster than harder rock, even on gentler slopes, making rock strength a primary control on mountain erosion. The finding challenges long-held assumptions in geomorphology that slope and tectonic uplift dominate erosion rates. By analyzing mountain landscapes, researchers found that soft rock loses material much more quickly, which has significant implications for carbon cycling. Erosion of uplifted rock can release carbon dioxide through chemical weathering, and current models may underestimate CO₂ contributions from mountainous regions. The study suggests that geologists and atmospheric scientists need to account for rock strength when calculating erosion and associated carbon fluxes. Lead author and UMass Amherst geoscientist Isaac Larsen emphasizes that this overlooked factor could alter predictions of landscape evolution and climate feedbacks. The research underscores the need to refine climate models with more accurate erosion data from diverse rock types. Ultimately, understanding how soft rock accelerates erosion will improve projections of long-term carbon release from Earth's surface.