Losses outlast gains in Northern Hemisphere tree growth under climate change
Year: 2026
Type: preprint
Abstract: Under climate change, will forests grow more or less? The answer differs from place to place, obscuring the overall direction. Here we trace it by learning nonlinear climate–tree-growth relationships from 4,110 Northern Hemisphere tree-ring chronologies recorded since 1902, spanning more than 12 million ring-width measurements, and projecting them through the twenty-first century under CMIP6 scenarios. Projected growth declines, and gains and losses are temporally asymmetric: once losses emerge, they are rarely reversed (90% retained), whereas gains fade (56% retained). This asymmetry holds in every well-sampled region and strengthens under higher forcing. The decline itself is driven by warming and rising atmospheric water demand, whose broadly negative contribution outweighs precipitation-driven gains. Across the Northern Hemisphere, growth does not just move between gains and losses; it is drawn steadily downward.
Language: English
Topic: Tree-ring climate responses
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDGs: Climate action, Life on land
Open Access status: green
OpenAlex ID: W7212419119