The AmeriFlux Tech Team has completed another successful site visit season. This year they visited nine AmeriFlux sites. The below gallery features an image from each site visit. The Tech Team is planning for the upcoming site visit season. If you would like to learn more about site visits and what to expect, please see our… More

Aerodynamic canopy height (ha) is the effective height of vegetation canopy for its influence on atmospheric fluxes and is a key parameter of surface‐atmosphere coupling. However, methods to estimate ha from data are limited. This synthesis evaluates the applicability and robustness of the calculation of ha from eddy covariance momentum‐flux data. At 69 forest sites,… More

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The vast forests and natural areas of the Pacific Northwest compose one of the most productive ecosystems in the Northern Hemisphere. The heterogeneous landscape of Oregon poses a particular challenge to ecosystem models. This study presents a framework using a scaling factor Bayesian inversion to improve the modeled atmosphere–biosphere exchange of CO2. Observations from five… More

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The Pacific Northwest (PNW) region of the United States has some of the most productive forests in the world. As precipitation regimes may shift with changing climate in this area, droughts are predicted to increase in both frequency and degree of severity, which will have a significant impact on already drought-prone ecosystems. When modeling ecosystem… More

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The possibility of global, three-dimensional remote sensing of forest structure with interferometric synthetic aperture radar (InSAR) bears on important forest ecological processes, particularly the carbon cycle. InSAR supplements two-dimensional remote sensing with information in the vertical dimension. Its strengths in potential for global coverage complement those of lidar (light detecting and ranging), which has the… More

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Sources and sinks of carbon associated with forests depend strongly on the management regime and spatial patterns in potential productivity. Satellite remote sensing can provide spatially explicit information on land cover, stand-age class, and harvesting. Carbon-cycle process models coupled to regional climate databases can provide information on potential rates of production and related rates of… More

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A new observational approach is presented to approximate the uncertainty (scatter or error variance) in 1-h averaged turbulence fluxes from eddy-covariance measurements. The uncertainty includes potential contributions from instrument problems, heterogeneity and non-stationarity in addition to classical random sampling error. The daytime relative flux uncertainty (RFE) is half as large (20%) at a simple maize… More

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Net ecosystem production (NEP) was estimated over a 10.9 × 104 km2 forested region in western Oregon USA for 2 yr (2002–2003) using a combination of remote sensing, distributed meteorological data, and a carbon cycle model (CFLUX). High spatial resolution satellite data (Landsat, 30 m) provided information on land cover and the disturbance regime. Coarser… More

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Summer drought is a feature of the semi-arid region of central Oregon, USA, where vegetation naturally develops into ponderosa pine (Pinus ponderosa var. Laws) forest. Forest management consists of clearcut harvest and natural regeneration. Soil microbial activity is interconnected with forest processes because substrate quality and availability can be important driving variables. Stand development influences… More

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