Arctic‐boreal landscapes are experiencing profound warming, along with changes in ecosystem moisture status and disturbance from fire. This region is of global importance in terms of carbon feedbacks to climate, yet the sign (sink or source) and magnitude of the Arctic‐boreal carbon budget within recent years remains highly uncertain. Here, we provide new estimates of recent (2003–2015) vegetation gross primary productivity (GPP), ecosystem respiration (
The Arctic is warming at twice the rate of the global mean. This warming could further stimulate methane (CH4) emissions from northern wetlands and enhance the greenhouse impact of this region. Arctic wetlands are extremely heterogeneous in terms of geochemistry, vegetation, microtopography, and hydrology, and therefore CH4fluxes can differ dramatically within the metre scale. Eddy covariance (EC) is one of the most useful methods for estimating CH4fluxes in remote areas over long periods of time. However, when the areas sampled by these EC towers (i.e. tower footprints) are by definition very heterogeneous, due to encompassing a variety of environmental conditions and vegetation types, modelling environmental controls of CH4emissions becomes even more challenging, confounding efforts to reduce uncertainty in baseline CH4emissions from these landscapes. In this study, we evaluated the effect of footprint variability on CH4fluxes from two EC towers located in wetlands on the North Slope of Alaska. The local domain of each of these sites contains well developed polygonal tundra as well as a drained thermokarst lake basin. We found that the spatiotemporal variability of the footprint, has a significant influence on the observed CH4fluxes, contributing between 3% and 33% of the variance, depending on site, time period, more »
- Publication Date:
- NSF-PAR ID:
- 10303215
- Journal Name:
- Environmental Research Letters
- Volume:
- 14
- Issue:
- 12
- Page Range or eLocation-ID:
- Article No. 125010
- ISSN:
- 1748-9326
- Publisher:
- IOP Publishing
- Sponsoring Org:
- National Science Foundation
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