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ChEAS 2005. Estimation of regional CO2 fluxes using concentration measurements from a ring of towers. Marek Uliasz, Andrew Schuh & Scott Denning Department of Atmospheric Science Colorado State University. Inversion experiments using CO 2 pseudo-data. RAMS. meteorological fields. LPDM.
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ChEAS 2005 Estimation of regional CO2 fluxes using concentration measurements from a ring of towers Marek Uliasz, Andrew Schuh & Scott Denning Department of Atmospheric Science Colorado State University
Inversion experiments using CO2 pseudo-data
RAMS meteorological fields LPDM
RAMS meteorological fields LPDM influence functions CO2 observations
RAMS meteorological fields a-priori estimates of CO2 surface & inflow fluxes LPDM inversions influence functions CO2 observations CO2 flux estimate
Example of estimation of NEE averaged for August 2000 • Bayesian inversion technique using influence function derived from CSU RAMS and Lagrangian particle model • flux estimation for source areas in polar coordinates within 400 km from WLEF tower (better coverage by atmospheric transport) • NEE decomposed into respiration and assimilation fluxes: R=R0, A=A0 f(short wave radiation, vegetation class) • inversion calculations for increasing number of concentration data (time series from towers) • NEE uncertainty presented in terms of standard deviation derived from posteriori covariance matrix • inflow CO2 flux is assumed to be known from a large scale transport model in further work, concentration data from additional tower will be used to improve the inflow flux given by a large scale model Configuration of source areas with WLEF tower in the center of polar coordinates
Conclusions from pseudo-data inversion: Successful inversions for surface fluxes as long as inflow flux is known Difficulty to handle inflow flux(es) as unknown parameter in inversions
RAMS meteorological fields a-priori estimates of CO2 surface & inflow fluxes LPDM inversions influence functions CO2 observations CO2 flux estimate
SiB-RAMS CO2 fields CO2 fluxes meteorological fields a-priori estimates of CO2 surface & inflow fluxes LPDM inversions influence functions CO2 observations CO2 flux estimate
PCTM SiB-RAMS LPDM
PCTM SiB-RAMS LPDM off-line transport model forward/backward model Lagrangian particle model
PCTM SiB-RAMS LPDM ?
PCTM SiB-RAMS LPDM meteorological fields CO2 fields and fluxes other fields
SiB-RAMS simulation summer 2004 2 nested grids 2001 NDVI by Andrew Schuh
influence function for concentration measurements C* concentration sample surface fluxes initial concentration inflow fluxes
modeling approach to CO2 data analysis Cold front passage across the ring Application of influence functions to analyze CO2 episodes
The Ring of Towers = 40m Sylvania flux tower with high-quality standard gases. = LI-820 sampling from 75m above ground on communication towers. = 447m WLEF tower. LI-820, CMDL in situ and flask measurements. data provided by Ken Davis, Scott J. Richardson and Natasha Miles, The Pennsylvania State University
CO2 from 5 sites, April 29, 2004 1200UTC Ken Davis, Scott J. Richardson and Natasha Miles The Pennsylvania State University
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