Northward shift of boreal tree cover confirmed by satellite record
Abstract. The boreal forest has experienced the fastest warming of any forested biome in recent decades. While vegetation–climate models predict a northward migration of boreal tree cover, the long-term studies required to test the hypothesis have been confined to regional analyses, general indices of vegetation productivity, and data calibrated to other ecoregions. Here we report a comprehensive test of the magnitude, direction, and significance of changes in the distribution of the boreal forest based on the longest and highest-resolution time-series of calibrated satellite maps of tree cover to date. From 1985 to 2020, boreal tree cover expanded by 0.844 million km2, a 12 % relative increase since 1985, and shifted northward by 0.29° mean and 0.43° median latitude. Gains were concentrated between 64–68° N and exceeded losses at southern margins, despite stable disturbance rates across most latitudes. Forest age distributions reveal that young stands (up to 36 years) now comprise 15.4 % of forest area and hold 1.1–5.9 Pg of aboveground biomass carbon, with the potential to sequester an additional 2.3–3.8 Pg C if allowed to mature. These findings confirm the northward advance of the boreal forest and implicate the future importance of the region's greening to the global carbon budget.
Authors
- Christopher S.R. Neigh (ORCID: https://orcid.org/0000-0002-5322-6340)
- Akiko Elders (ORCID: https://orcid.org/0000-0001-7706-1846)
- Ming Feng (ORCID: https://orcid.org/0000-0002-2855-7092)
- Leonardo Calle (ORCID: https://orcid.org/0000-0002-0269-6115)
- Saurabh Channan (ORCID: https://orcid.org/0000-0002-9923-0740)
- Michael A. Wulder (ORCID: https://orcid.org/0000-0002-6942-1896)
- Panshi Wang (ORCID: https://orcid.org/0000-0003-4063-1571)
- Margaret Wooten (ORCID: https://orcid.org/0000-0002-5259-757X)
- Matthew J. Macander (ORCID: https://orcid.org/0000-0003-2808-208X)
- Nuno Carvalhais
- Joseph O. Sexton
- William Wagner
- Benjamin Poulter
Institutions
- Canadian Forest Service (CA)
- Natural Resources Canada (CA)
- Goddard Space Flight Center (US)
- Climate Central (US)
- Chinese Academy of Sciences (CN)
- University of the Potomac (US)
- Institute of Tibetan Plateau Research (CN)
- Science Systems and Applications (United States) (US)
- Max Planck Institute for Biogeochemistry (DE)
- Alaska Biological Research (United States) (US)
- Adnet Systems (United States) (US)
- University of Maryland, College Park (US)
- University of Montana (US)
- Universidade Nova de Lisboa (PT)
- Morgan State University (US)
Publication Details
- Journal
- Biogeosciences
- Published
- 2026-02-05
- DOI
- https://doi.org/10.5194/bg-23-1089-2026
- Primary Topic
- Remote Sensing in Agriculture
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Science Foundation
- National Aeronautics and Space Administration
- Amazon Web Services
- Nuclear Safety and Security Commission
- Goddard Space Flight Center