Nitrous oxide emissions from pan-Arctic terrestrial ecosystems: A process-based biogeochemistry model analysis from 1969 to 2019
Nitrous oxide (N 2 O) is a potent greenhouse gas with radiative forcing 265–298 times stronger than that of carbon dioxide (CO 2 ). Increasing atmospheric N 2 O burden also contributes to stratospheric ozone depletion. Recent field studies show N 2 O emissions from the Arctic ecosystems have increas...
| Main Authors: | , , , |
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| Format: | Text |
| Language: | English |
| Published: |
2023
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| Subjects: | |
| Online Access: | https://doi.org/10.5194/egusphere-2023-1047 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-1047/ |
| Summary: | Nitrous oxide (N 2 O) is a potent greenhouse gas with radiative forcing 265–298 times stronger than that of carbon dioxide (CO 2 ). Increasing atmospheric N 2 O burden also contributes to stratospheric ozone depletion. Recent field studies show N 2 O emissions from the Arctic ecosystems have increased due to warming. To date, the emissions across space and time have not been adequately quantified. Here we revised an extant process-based biogeochemistry model, the Terrestrial Ecosystem Model (TEM) to incorporate more detailed processes of soil biogeochemical nitrogen (N) cycle, permafrost thawing effects, and atmospheric N 2 O uptake in soils. The model is then used to analyze N 2 O emissions from pan-Arctic terrestrial ecosystems. We find that both regional N 2 O production and net emissions increased from 1969 to 2019, with production ranging from 1.2–1.3 Tg N yr -1 and net emissions from 1.1–1.2 Tg N yr -1 considering the permafrost thaw effects. Soil N 2 O uptake from the atmosphere was 0.1 Tg N yr -1 with a small interannual variability. Atmospheric N deposition significantly increased N 2 O emission by 31.5 ± 3.1 %. Spatially, terrestrial ecosystems act as net sources or sinks ranging from -12 to 700 mg N m -2 yr -1 depending on temperature, precipitation, soil characteristics, and vegetation types in the region. |
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