HR: 09:30h
AN: G51D-07    [Abstracts]
TI: An Atmospheric Turbulence-Based GPS Stochastic Model
AU: * Kleijer, F
EM: fkleijer@cfa.harvard.edu
AF: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 United States
AU: Elosegui, P
EM: pelosegui@cfa.harvard.edu
AF: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 United States
AU: Elosegui, P
EM: pelosegui@cfa.harvard.edu
AF: Institut Estudis Espacials Catalunya/CSIC, E-Nexus, Gran Capita 2, Barcelona, E-08034 Spain
AU: Davis, J L
EM: jdavis@cfa.harvard.edu
AF: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 United States
AB: The precision of GPS position estimates depends on several error sources. One of the limiting GPS error sources is due to fluctuations of water vapor content in the atmosphere, which causes variations in slant-path propagation delays. In GPS data processing, atmospheric propagation delays are typically modeled using a simplified parametric model that does not fully account for water vapor fluctuations. We have developed a stochastic model for delay variations in GPS that is based on the fluctuations of the atmospheric refractive index. We have implemented this model in a least-squares method and, using GPS data, have thus the ability to estimate a site-dependent, time-varying turbulence strength parameter. Preliminary results are very promising and suggest that turbulence is an important error source in GPS. We will describe this variance-covariance model and the scaling turbulence variance estimates. These results may have implications for the interpretation of signals, and its separation from noise, in analysis of GPS time series, and may benefit both geodesists and meteorologists.
DE: 1704 Atmospheric sciences
DE: 1709 Geodesy
DE: 0689 Wave propagation (4275)
SC: Geodesy [G]
MN: 2004 AGU Fall Meeting