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Climate-induced northward advance of boreal forest is expected to lessen albedo, alter carbon stocks, and replace tundra, but where and when this advance will occur remains largely unknown. Using data from 19 sites across 22 degrees of longitude along the tree line of northern Alaska, we show a stronger temporal correlation of tree ring growth with open water uncovered by retreating Arctic sea ice than with air temperature. Spatially, our results suggest that tree growth, recruitment, and range expansion are causally linked to open water through associated warmer temperatures, deeper snowpacks, and improved nutrient availability. We apply a meta-analysis to 82 circumarctic sites, finding that proportionally more tree lines have advanced where proximal to ongoing sea ice loss. Taken together, these findings underpin how and where changing sea ice conditions facilitate high-latitude forest advance.
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Environmental constraints on transpiration and stomatal conductance in a Siberian Arctic boreal forest: TRANSPIRATION IN AN ARCTIC BOREAL FOREST
- Award ID(s):
- 1417700
- PAR ID:
- 10027549
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Biogeosciences
- Volume:
- 122
- Issue:
- 3
- ISSN:
- 2169-8953
- Page Range / eLocation ID:
- 487 to 497
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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