Arctic soil governs whether climate change drives global losses or gains in soil carbon

Abstract

Key uncertainties in terrestrial carbon cycle projections revolve around the timing, direction, and magnitude of the carbon cycle feedback to climate change. This is especially true in carbon‐rich Arctic ecosystems, where permafrost soils contain roughly one third of the world's soil carbon stocks, which are likely vulnerable to loss. Using an ensemble of soil biogeochemical models that reflect recent changes in the conceptual understanding of factors responsible for soil carbon persistence, we quantify potential soil carbon responses under two representative climate change scenarios. Our results illustrate that models disagree on the sign and magnitude of global soil changes through 2100, with disagreements primarily driven by divergent responses of Arctic systems. These results largely reflect different assumptions about the nature of soil carbon persistence and vulnerabilities, underscoring the challenges associated with setting allowable greenhouse gas emission targets that will limit global warming to 1.5°C.

Journal Article
Year of Publication
2019
Author
Journal
Geophysical Research Letters
Volume
46
Issue
24
Number of Pages
14486 - 14495
Date Published
12/2019
DOI
10.1029/2019GL085543
Keywords
ISSN Number
0094-8276
URL
https://doi.org/10.1029/2019GL085543
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