HR: 1330h
AN: A52B-0784    [PDF]
TI: Modeling CO2 profiles for satellite validation
AU: Pickett - Heaps, C A
EM: christopher.pickett-heaps@csiro.au
AF: CSIRO Atmospheric Research, PMB 1, Aspendale, VIC 3195
AU: * Rayner, P J
EM: peter.rayner@csiro.au
AF: CSIRO Atmospheric Research, PMB 1, Aspendale, VIC 3195
AU: Law, R M
EM: rachel.law@csiro.au
AF: CSIRO Atmospheric Research, PMB 1, Aspendale, VIC 3195
AU: Kowalczek, E
EM: eva.kowalczek@csiro.au
AF: CSIRO Atmospheric Research, PMB 1, Aspendale, VIC 3195
AU: Langenfelds, R L
EM: ray.langenfelds@csiro.au
AF: CSIRO Atmospheric Research, PMB 1, Aspendale, VIC 3195
AB: The Orbiting Carbon Observatory (OCO) is a NASA satellite mission, scheduled for launch in 2007, that is intended to provide spatially dense measurements of the column-integrated CO2 mixing ratio. Like any such mission, OCO faces the problem of calibration and validation. In particular, both to allow the use of its data along with existing CO2 measurements for source-sink estimation and to avoid potential systematic errors in the satellite measurements, OCO data must be tied to the existing precise but sparse surface measurement network. This is difficult since we rarely if ever measure the same, column-integrated mixing ratio as OCO. A possible technique uses upward looking Fourier Transform Spectrometers to provide a ground-based measurement of the column-integrated mixing ratio. Now the problem shifts to the calibration and validation of these instruments. Aircraft profiling, in which discreet CO2 measurements are taken at a range of heights, provides one obvious link. However aircraft cannot fly to the top of the atmosphere and the question remains of how reliable a calibration can be provided by a profile to any given level. This poster investigates this problem by modelling the 3-dimensional CO2 field using climatological CO2 sources and an atmospheric transport model (The CSIRO Cubic Conformal Model) driven with observed meteorological forcing. We compare the modelled vertical profiles with those measured in several campaigns, most notably the decade-long series at Cape Grim, Tasmania. Next we consider the ability of a profile at various locations to represent the column-integrated mixing ratio. We consider variations both by season and location in order to suggest an optimal strategy for the use of aircraft profiles as a validation tool.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting