Climate warming shortens mast intervals by accelerating resource accumulation in the Northern Hemisphere

Masting shapes forest regeneration and ecosystem dynamics through intermittent, synchronized seed production. However, how climate warming alters mast intervals and the resource dynamics underlying reproductive recurrence remains unclear. Here we compiled 61,754 long-term seed production records from 700 species across 1,987 sites in the Northern Hemisphere to quantify changes in mast intervals and their associations with energy and resource accumulation. We show that climate warming shortens mast intervals, accompanied by faster resource acquisition and lower cumulative resource accumulation preceding mast recurrence. This warming-induced shortening was widespread but more pronounced in temperate regions, where annual thermal accumulation increased more rapidly, and in gymnosperms, which are characterized by conservative resource-use strategies. CMIP6 projections indicate further shortening of mast intervals under future climate warming. Our results suggest that climate warming is reshaping mast seeding by accelerating resource accumulation and reducing the cumulative resource thresholds required between mast events, with important implications for tree recruitment, consumer-resource dynamics and yield stability in perennial plant production systems.