FLUXNET
"FLUXNET is a global network of micrometeorological flux measurement sites that measure the exchanges of carbon dioxide, water vapor, and energy between the biosphere and atmosphere. At present over 140 sites are operating on a long-term and continuous basis. Vegetation under study includes temperate conifer and broadleaved (deciduous and evergreen) forests, tropical and boreal forests, crops, grasslands, chaparral, wetlands, and tundra. Sites exist on five continents and their latitudinal distribution ranges from 70°N to 30°S." (Baldocchi, 2001)
The flux tower sites use eddy covariance methods to measure the exchanges of carbon dioxide (CO2), water vapor, and energy between terrestrial ecosystems and the atmosphere.
Key Strengths
Over 500 tower sites are operated on a long-term and continuous basis with a wide range of vegetation types.
Key Limitations
Most flux tower sites have data gaps and some have energy and water balance closure problems
Data spread out over multiple download sites. Inconvenient!
Key Figures
FLUXNET [source: http://daac.ornl.gov//FLUXNET/Sky_Oaks_new.jpg ]
FLUXNET: Net Ecosystem Exchange CO2, latent and sensible heat for 1992 at Harvard Forest: Total (blue), Day (red), Night (green). [Climate Data Guide; D. Shea]
Other Information
Typical flux tower site footprint (~km)
- Baldocchi, D., et al. (2001), FLUXNET: A new tool to study the tempo- ral and spatial variability of ecosystem‐scale carbon dioxide, water vapor, and energy flux densities, Bull. Am. Meteorol. Soc., 82(11), 2415–2434
- Mueller, B., et al. (2011), Evaluation of global observations‐based evapotranspiration datasets and IPCC AR4 simulations, Geophys. Res. Lett., 38, L06402
- Jung, M, Reichstein, M, Bondeau, A (2009). Towards global empirical upscaling of FLUXNET eddy covariance observations: validation of a model tree ensemble approach using a biosphere model. BIOGEOSCIENCES, 6(10), 2001-2013
- Baldocchi, D. (2008). ‘Breathing’ of the terrestrial biosphere: Lessons learned from a global network of carbon dioxide flux measurement systems. Australian Journal of Botany, 56, 1-26