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Abstract Arctic warming can influence tundra ecosystem function with consequences for climate feedbacks, wildlife and human communities. Yet ecological change across the Arctic tundra biome remains poorly quantified due to field measurement limitations and reliance on coarse-resolution satellite data. Here, we assess decadal changes in Arctic tundra greenness using time series from the 30 m resolution Landsat satellites. From 1985 to 2016 tundra greenness increased (greening) at ~37.3% of sampling sites and decreased (browning) at ~4.7% of sampling sites. Greening occurred most often at warm sampling sites with increased summer air temperature, soil temperature, and soil moisture, while browning occurred most often at cold sampling sites that cooled and dried. Tundra greenness was positively correlated with graminoid, shrub, and ecosystem productivity measured at field sites. Our results support the hypothesis that summer warming stimulated plant productivity across much, but not all, of the Arctic tundra biome during recent decades.
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Tundra greenness
Highlights•In North America, tundra productivity for the 2019 growing season (the most recent data available) rebounded strongly from the previous year, in tandem with record summer warmth following the cold summer of 2018.•Since 2016, greenness trends have diverged strongly by continent; peak summer greenness has declined sharply in North America but has remained above the long-term mean in Eurasia.•The long-term satellite record (1982-2019) indicates "greening" across most of the Arctic but some regions exhibit "browning," underscoring the dynamic linkages that exist between tundra ecosystems and other elements of a changing Arctic system.
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- Award ID(s):
- 1928237
- PAR ID:
- 10284206
- Editor(s):
- J. Richter-Menge, M. L.
- Date Published:
- Journal Name:
- Bulletin of the American Meteorological Society
- ISSN:
- 1520-0477
- Page Range / eLocation ID:
- S1–S429
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1175/BAMS-D-20-0086.
