We are happy to start the new year with the publication of the first topical review from the Nordic Borealization Network, where we introduce the concept of tundra borealization to describe northward and upward shifts of boreal species into tundra ecosystems — a key yet still underrecognized dimension of climate-driven ecological change.
In this synthesis, we:
- clarify how borealization is defined across disciplines and environments
- summarise evidence of plant and animal community changes in tundra systems
- review methods for quantifying borealization
- discuss how climate and land-use change drive species reorganization
By bridging ecology, biogeography, climate science, and socio-ecological research, this work advances theoretical understanding of ecosystem responses to global environmental change. Given the implications for biodiversity, ecosystem functioning, climate feedbacks, and Arctic livelihoods, we hope it will support both research and adaptation efforts.
Reference: Verdonen, M., Barrio, I. C., Barbero-Palacios, L., López-Blanco, E., Speed, J. D. M., Defourneaux, M., García Criado, M., Moullec, M. le, Mellard, J. P., Salazar, A., Bakke Westergaard, K., Guðmundsson, J., Schmidt, N. M., Sigurdsson, B. D., Austrheim, G., Bjorkman, A. D., Björnsdóttir, K., Jepsen, J. U., Pagneux, E. P., Trascau, B.M., Williamson, D.R., Aradóttir, Á.L., Barry, A., Bernard, T., Koivisto, E., Kumpula, T., Villoslada, M., Myers-Smith, I. H. (2026). Borealization of tundra ecosystems with climate and land-use change. Environmental Research Letters, 21(1), 013002. https://doi.org/10.1088/1748-9326/ae2e18
Photo: Birch trees growing on a ridge in Kilpisjärvi, Finland. Credit: Mariana García Criado