Cited by 55Climate change and permafrostPolar Research and EcologyRemote Sensing in Agriculture

The changing face of the Arctic: four decades of greening and implications for tundra ecosystems

Open access
Frost, Gerald V., Bhatt, Uma S., Macander, Matthew J., Berner, Logan T., Walker, Donald A., Raynolds, Martha K., Magnússon, Rúna Í., Bartsch, Annett +24 more·2025·Frontiers in Environmental Science

Abstract

Arctic landscapes occupy a nexus of environmental change processes, globally significant soil carbon stores, wildlife populations, and subsistence-based human societies. In response to rapid climate warming, tundra ecosystems are experiencing widespread changes to vegetation and underlying permafrost, coupled with an array of ecological disturbances that are expected to intensify in the future. Declines in the extent of the cryosphere on land (permafrost and seasonal snow) and offshore (sea-ice) raise the question of whether and for how long warmer portions of the Low Arctic will fit established concepts of “what is Arctic,” given the influence the cryosphere has historically had on tundra ecosystem structure and function. The era of spaceborne observation of circumpolar tundra greenness, in the form of the Normalized Difference Vegetation Index (NDVI), has entered its fifth decade and provides foundational information concerning ecosystem conditions and responses to climatic trends, variability, ecological disturbance, and successional processes. Here we review the evolving story of Arctic greening, and synthesize long-term spaceborne records of NDVI, climatic data, field observations, and the knowledge base of Arctic residents to place the last four decades of Arctic environmental change in context, and establish expectations and research priorities for the coming decade. Greenness dynamics display high spatio-temporal variability, reflecting complex interactions of climatic warming and variability, landscape history, ecological disturbance, and other factors. Nonetheless, long-term increases in NDVI—commonly known as “the greening of the Arctic”—remain prominent across large areas in all available long-term spaceborne datasets and align with long-term shifts in vegetation structure documented in disparate Arctic regions. Common shifts reported from the Low Arctic, such as shrubification, generally portend declines in floristic diversity, and shifts in fauna that favor boreal forest species. Despite lingering uncertainties regarding trend attribution and sources of interannual variability, the sequence of record-high circumpolar tundra greenness values observed since 2020 provides strong evidence that Arctic tundra ecosystems have entered a state without historic precedent on timescales approaching a millennium.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.3389/fenvs.2025.1525574

Cites

306 of 308 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • MODIS and Landsat records generally display less interannual variability in MaxNDVI than the legacy GIMMS-3g+ dataset, likely reflecting their higher spatial resolution and improved calibration.

    “The latter two records generally display less interannual variability in MaxNDVI than the legacy GIMMS-3g+ dataset, likely reflecting their higher spatial resolution and improved calibration (Frost et al. 2025).”

    From NOAA Arctic Report Card 2025: Tundra Greenness (2025) · cites this paper as Frost et al. 2025

    Section 2.4 (p. 7) reports much lower interannual MaxNDVI variability in the MODIS and Landsat records than in GIMMS-3g+ during the 2020–2021 decline. The methods (p. 5) establish that MODIS and Landsat have higher spatial resolution, but the paper does not attribute their lower variability to spatial resolution or improved calibration. (LLM, conf=0.85)

    Experimental — accuracy not yet measured
  • Increases in the abundance, distribution, and height of Arctic shrubs are a major component of Arctic greening.

    “Increases in the abundance, distribution, and height of Arctic shrubs are a major component of Arctic greening (Frost et al. 2025).”

    From NOAA Arctic Report Card 2025: Tundra Greenness (2025) · cites this paper as Frost et al. 2025

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 7

  1. Didan, K., and Barreto, A. (2018). VIIRS/NPP vegetation indices 16-day L3 global 500m SIN grid V001 . doi:10.5067/VIIRS/VNP13A1.001 · DOI
  2. Frost, G. V., Macander, M. J., Bhatt, U. S., Berner, L. T., Bjerke, J. W., Epstein, H. E., et al. (2024). Tundra greenness [in ' state of the climate in 2023 ' ]. Bull. Am. Meteorological Soc. 105, S305 -S308. doi:10.1175/BAMS-D-24-0101.1 · DOI
  3. Magnússon, R. Í., Limpens, J., Kleijn, D., van Huissteden, K., Maximov, T. C., Lobry, S., et al. (2021b). Shrub decline and expansion of wetland vegetation revealed by very high resolution land cover change detection in the Siberian lowland tundra. Sci. Total Environ. 782, 146877. doi:10.1016/j.scitotenv.2021.146877 · DOI
  4. Rupp, T. S., Star fi eld, A. M., and Chapin, F. S. (2000). A frame-based spatially explicit model of subarctic vegetation response to climatic change: comparison with a point model. Landsc. Ecol. 15, 383 -400. doi:10.1023/A:1008168418778 · DOI
  5. Ukraintseva, N. G., and Leibman, M. O. (2007). ' The effect of cryogenic landslides (active-layer detachments) on fertility of tundra soils on Yamal Peninsula, Russia, ' in Proceedings of the 1st North American landslide conference (Vail, CO, United States: Omnipress), 1605 -1615.
  6. Von Baeckmann, C., Bartsch, A., Bergstedt, H., E fi mova, A., Widhalm, B., Ehrich, D., et al. (2024). Landcover succession for recently drained lakes in permafrost on the Yamal peninsula. West. Sib. doi:10.5194/egusphere-2024-699 · DOI
  7. Walker, D. A., Raynolds, M. K., Daniëls, F. J. A., Einarsson, E., Elvebakk, A., Gould, W. A., et al. (2005b). The circumpolar Arctic vegetation map. J. Veg. Sci. 16, 267 -282. doi:10.1658/1100-9233(2005)016[0267:tcavm]2.0.co;2 · DOI

Cited by

Sorted by citations

Authors
Frost, G. V., Bhatt, U. S., Macander, M. J., Berner, L. T., Walker, D. A., Raynolds, M. K., Magnússon, R. Í., Bartsch, A., Bjerke, J. W., Epstein, H. E., Forbes, B. C., Goetz, S. J., Hoy, E. E., Karlsen, S. R., Kumpula, T., Lantz, T. C., Lara, M. J., López-Blanco, E., Montesano, P. M., Neigh, C. S. R., Nitze, I., Orndahl, K. M., Park, T., Phoenix, G. K., Rocha, A. V., Rogers, B. M., Schaepman-Strub, G., Tømmervik, H., Verdonen, M., Veremeeva, A., Virkkala, A.-M., & Waigl, C. F.
Affiliations
  • Alaska Biological Research (United States) (US)
  • University of Alaska Fairbanks (US)
  • Northern Arizona University (US)
  • Wageningen University & Research (NL)
  • b.geos (AT)
  • Norwegian Institute for Nature Research (NO)
  • University of Virginia (US)
  • University of Lapland (FI)
  • Goddard Space Flight Center (US)
  • NORCE Research AS (NO)
  • University of Eastern Finland (FI)
  • University of Victoria (CA)
  • University of Illinois Urbana-Champaign (US)
  • Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung (DE)
  • Ames Research Center (US)
  • University of Sheffield (GB)
  • University of Notre Dame (US)
  • Woodwell Climate Research Center (US)
  • Agricultural University of Iceland (IS)
Corresponding author
Frost, Gerald V.
Venue
Frontiers in Environmental Science
Published
2025-04-10
Volume
13
ISSN
2296-665X (ISSN-L)
OpenAlex
W4409329826
Cited by
51
References
308
Citations by year
2026: 39 · 2025: 12
FWCI
22.15
Type
journal article
Language
en
Open access
Locations
  • Frontiers in Environmental Science (publishedVersion, cc-by)
  • White Rose Research Online (University of Leeds, The University of Sheffield, University of York) (acceptedVersion)
  • Zurich Open Repository and Archive (University of Zurich) (acceptedVersion, cc-by)
  • Socio-Environmental Systems Modeling (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Zurich Open Repository and Archive (University of Zurich) (submittedVersion, cc-by)
  • Zurich Open Repository and Archive (University of Zurich)
Funders
National Aeronautics and Space Administration (80NSSC22K1256)
Topics
  • Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Climate change and permafrost
  • Physical Sciences › Environmental Science › Ecology › Polar Research and Ecology
  • Physical Sciences › Environmental Science › Ecology › Remote Sensing in Agriculture
Keywords
Arctic greening, tundra ecosystems, NDVI, global warming, permafrost thaw, shrubification, vegetation change, sea ice decline, Low Arctic, long-term satellite records, floristic diversity, environmental disturbance, indigenous knowledge

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review