PaC provides provisional summaries of carbon flux for the US, based on the direct measurement of CO₂ by eddy covariance within the forest and related terrestrial project areas reported for NEON and Ameriflux sites. While these data are representative of the characteristic footprint for each site, and may not fully represent surrounding regions, PaC is employing this data as a first step in creating a verifiable direct measurement program for a US National carbon trading system.

Note: the data employed in PaC carbon portfolios are for illustration purposes only and are not in any way officially endorsed by the NEON or Ameriflux organizations. All terms and conditions for data reporting, data quality control, and download instructions can be found on the respective webpages cited below. 

NEON provides the only freely accessible and integrated network of CO₂ dynamics for the Continental US. 47 NEON sites are distributed across the US partitioned into 20 ecoregions. Learn more about NEON here: NEON.

The AmeriFlux network is a community of sites and scientists measuring ecosystem carbon, water, and energy fluxes across the Americas, and committed to producing and sharing high-quality eddy covariance data. AmeriFlux investigators and modelers work together to generate an understanding of terrestrial ecosystems in a changing world. Learn more about Ameriflux here: Ameriflux.

The charts below represent current NEON and Ameriflux data for Net Ecosystem Exchange (NEE) and corresponding ecosystem respiration (R_eco). NEE shows the total metric tons of CO₂ (tCO₂equivalent) sequestered as net forest carbon (NEE). The ecosystem respiration is also represented as tCO₂equivalent.

The portfolio builder provides users of the Gaia Monitor to study the US landscape through the lens of CO₂ flux.  Eddy covariance provides data for NEE, here defined as net forest carbon sequestration, which is partitioned into the components of Ecosystem Respiration (R_eco) and Gross Primary Production (GPP) according to Eq.1 using models that predict the rates of R_eco during daylight hours from nighttime observations when GPP is zero according to the following relationship:

NEE = GPP + Reco   (1).

Single sites or diverse portfolios of sites can be combined and analyzed with the portfolio builder. To use the portfolio builder, please login here.

An interactive map of the sites available through the portfolio builder is provided at the bottom of this page. Note that data are provided on a square meter area basis. The actual footprint area for each eddy covariance site is not reported. Extrapolation to larger areas or upscaling of a single site beyond the site footprint requires additional observations including remotely sensed data and appropriate models for the region.

Research towers map. It contains all the sites from FluxNet and NEON databases that have at least one year with > 80% of NEE data. FluxNet dataset can be found in https://fluxnet.org/, while NEON data can be downloaded from AmeriFlux network (https://ameriflux.lbl.gov/). The left panel allows adding/remove different layers useful to understand NEE dynamics. PEM fully acknowledges these institutions and the stewardship and terms of usage of all data products. PEM thanks all researchers who have worked tirelessly to set up, maintain and report all flux data that are represented by the sites on this map and as sites employed by the Gaia Monitor Portfolio Builder.

Select the Site View or Portfolio View option.  Then select the site or sites of interest. Select two pricing options and two area options. Then select SUBMIT. Results representing a single site or results for a combined portfolio will be displayed including values for NEE, Reco, and GPP. Monthly values for NEE and pricing values are provided for the available time series. Compare and contrast portfolios from different regions and within regions.