HR: 0830h
AN: P51C-0466    [PDF]
TI: Representing Planetary Atmospheric Structures and Observables with Radio Occultation Transform Pairs
AU: * Kusza, K
EM: kusza@stanford.edu
AF: Stanford University, 350 Serra Mall, Stanford, CA 94305-9515 United States
AU: Tyler, G L
EM: len.tyler@stanford.edu
AF: Stanford University, 350 Serra Mall, Stanford, CA 94305-9515 United States
AB: Current methods for relating radio occultation observables (the bending angles) to the refractivity profile of a planetary atmosphere require significant numerical integration. Although accurate and valid, this approach does not clearly illustrate how changes in refractivity, based on physical parameters such as temperature, pressure, or number density, relate to changes in the observed bending angles, and vice versa. However, the radio occultation Abel transform does have one known transform pair directly relating refractivity to bending angle, as derived by Eshleman (1973). The radio occultation transform pair has the potential to allow direct understanding of how changes in atmospheric refractivity and the observed bending angles map to each other. The complete analytical form of the radio occultation transform pair is complicated, in part because the radio occultation Abel transform includes ray bending effects. However, it can be written out in terms of a series expansion. Assuming certain common atmospheric conditions, such as a thin atmosphere, allows significant simplification by keeping only a few terms of the series and does not affect the validity of the representation (Eshleman, 1996). These simplifications allow representation of atmospheric refractivity structures in terms of power law expressions with controllable constants that map directly to the observed bending angles. We evaluate the superposition of several power law refractivity terms to represent atmospheric structures for both thin and thick atmospheres, the errors introduced in the refractivity profiles at different levels of simplification, and make initial observations of how physical differences in a planetary atmosphere, expressed in terms of refractivity, map to changes in the observed bending angle. The radio occultation transform pair approach allows us to better understand how differences in the refractivity structure of a planetary atmosphere relate to changes in radio occultation observables, without numerical integration.
DE: 3260 Inverse theory
DE: 3346 Planetary meteorology (5445, 5739)
DE: 5409 Atmospheres--structure and dynamics
DE: 6904 Atmospheric propagation
DE: 6969 Remote sensing
SC: Planetary Sciences [P]
MN: 2003 Fall Meeting