Theoretical and Numerical Issues in Travel Time Tomography
Abstract
Results from perturbation theory for changes in ocean acoustic modal group speeds due to small environmental changes are investigated with regard to their applicability to inversion schemes for large scale trends in the ocean's thermal structure. In regions where adiabatic mode theory is applicable, the inverse problem for each vertical eigenmode consists of an integral equation whose kernel involves the eigenfunction and its frequency derivative. We give a proof for the so called third term problem' which requires equivalence between two dissimilar integrals relating the perturbations in the water column, the resulting perturbations in the acoustic eigenmode under consideration, and the frequency derivative of the eigenmode. We give numerical examples for the inversion kernel for four types of sound speed profiles, and then explore numerically the parameter range (amplitude and scale size) in which perturbation theory is accurate.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2000
- Accession Number
- ADA389973
Entities
People
- Arthur Bernard Baggeroer
- B. E. Mcdonald
- Brian Sperry
Organizations
- SACLANT ASW Research Centre