Permafrost nitrous oxide emissions observed on a landscape scale using the airborne eddy-covariance method
<p>The microbial by-product nitrous oxide (<span class="inline-formula">N<sub>2</sub>O</span>), a potent greenhouse gas and ozone depleting substance, has conventionally been assumed to have minimal emissions in permafrost regions. This assumption has been que...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2019-04-01
|
| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://www.atmos-chem-phys.net/19/4257/2019/acp-19-4257-2019.pdf |
| Summary: | <p>The microbial by-product nitrous oxide (<span class="inline-formula">N<sub>2</sub>O</span>), a potent greenhouse gas and ozone
depleting substance, has conventionally been assumed to have minimal
emissions in permafrost regions. This assumption has been questioned by
recent in situ studies which have demonstrated that some geologic features in
permafrost may, in fact, have elevated emissions comparable to those of
tropical soils. However, these recent studies, along with every known in situ
study focused on permafrost <span class="inline-formula">N<sub>2</sub>O</span> fluxes, have used chambers to examine
small areas (<span class="inline-formula"><50</span> m<span class="inline-formula"><sup>2</sup></span>). In late August 2013, we used the airborne
eddy-covariance technique to make in situ <span class="inline-formula">N<sub>2</sub>O</span> flux measurements over
the North Slope of Alaska from a low-flying aircraft spanning a much larger
area: around 310 km<span class="inline-formula"><sup>2</sup></span>. We observed large variability of <span class="inline-formula">N<sub>2</sub>O</span>
fluxes with many areas exhibiting negligible emissions. Still, the daily mean
averaged over our flight campaign was 3.8
(2.2–4.7) mg <span class="inline-formula">N<sub>2</sub>O</span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> with the 90 % confidence
interval shown in parentheses. If these measurements are representative of
the whole month, then the permafrost areas we observed emitted a total of
around 0.04–0.09 g m<span class="inline-formula"><sup>−2</sup></span> for August, which is comparable to what is
typically assumed to be the upper limit of yearly emissions for these
regions.</p> |
|---|---|
| ISSN: | 1680-7316 1680-7324 |