Steven Bottone
Mission Res. Corp., P. O. Drawer 719, Santa Barbara, CA 93102-0719
Henry L. Gray
Wayne A. Woodward
Southern Methodist Univ., Dallas, TX 75275
A possible indication of the existence of global climate warming is a negative trend for the travel time of an acoustic pulse along a fixed long path, or paths, in the ocean over a period of many years. Statistical methods for determining whether a significant long term trend is present in a given set of time series data of acoustic propagation times have been developed and, for illustration, applied to some specific travel-time time series generated by the MASIG and GFDL ocean models. For the multiple path case, line + noise models, where the noise is modeled as a multivariate autoregressive (AR) process are considered. It is shown that the time necessary to detect the presence of a warming trend in a time series for a single path is reduced by considering time series for multiple paths. [Work sponsored by ARPA.]