HR: 0830h
AN: B51E-1003    [PDF]
TI: Quantifying Representation and Using Representation Weights to Interpolate Flux Tower Measurements across the United States
AU: * Hargrove, W W
EM: hnw@fire.esd.ornl.gov
AF: Oak Ridge National Laboratory, P.O. Box 2008, M.S. 6407, Oak Ridge, TN 37831-6407 United States
AU: Hoffman, F M
EM: forrest@climate.ornl.gov
AF: Oak Ridge National Laboratory, P.O. Box 2008, M.S. 6407, Oak Ridge, TN 37831-6407 United States
AB: We are using a new multivariate statistical technique to quantitatively divide the lower 48 United States into a series of flux-relevant ecoregions. On the basis of these flux-relevant ecoregions, we will quantify the representativeness of the existing network of AmeriFlux towers, showing how well each ecoregion is represented by the current stations in the AmeriFlux network. Quantifying AmeriFlux representation will indicate the best locations where additional AmeriFlux towers should be placed. Using a "paint-by-number" approach, we are attempting to use the flux ecoregions as the statistical basis for extrapolating measurements made at the 52 actively-reporting AmeriFlux towers into a continuous 1-km grid across the United States seasonally. We will use the similarity of the suite of flux-relevant ecosystem characteristics to modify existing flux measurements and estimate fluxes within unmeasured flux ecoregions. Weights calculated for each environmental gradient will allow us to mix new "paint-by-number" colors, extending the process beyond the palette of existing flux measurements. The map of 2000 to 5000 flux ecoregions will produce a highly-resolved national map of estimated fluxes, and will be equivalent to creating thousands of new "virtual" flux towers across the nation. Once flux ecoregions and representation weights have been determined, it may be possible to use them to obtain an interpolated grid of the estimated flux at any point in time across the United States.
UR: http://research.esd.ornl.gov/~hnw/networks2
DE: 0315 Biosphere/atmosphere interactions
DE: 0614 Biological effects
DE: 1615 Biogeochemical processes (4805)
DE: 1655 Water cycles (1836)
DE: 1851 Plant ecology
SC: Biogeosciences [B]
MN: 2003 Fall Meeting