ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

2aAO13. ATOC-FACT arrival-time differences.

David Palmer

NOAA/Atlantic Oceanogr. and Meteorol. Lab., 4301 Rickenbacker Cswy., Miami, FL 33173

Leon Krige

Inst. for Maritime Technol., Simon's Town, 7995 South Africa

Geoff Brundrit

Univ. of Cape Town, Rondebosch, 7700 South Africa

Kurt Metzger

Univ. of Michigan, Ann Arbor, MI 48109-2122

The acoustic thermometry of ocean climate-feasibility ascension Cape Town (ATOC-FACT) propagation experiment took place during November and December of 1992. Explosive charges were detonated near the oceanic sound-channel axis at five locations in the South Atlantic off Cape Town. The resulting signals were recorded on bottom-mounted hydrophones at Ascension, Navy horizontal arrays off Bermuda, bottom-mounted hydrophones off Kaneohe and Wake and from a hydrophone array deployed from a research ship off Southern Tasmania. The primary goal of the experiment was to determine the extent that the acoustic path between Ascension and Cape Town is blocked by Bonaparte's Seamount and other bathymetric features. Secondary goals were to determine the horizontal arrival structure at Bermuda and the temporal arrival structure at Ascension, Hawaii, and off Tasmania. After giving an overview of the experiment, we use recorded data to discuss the question of how precisely arrival-time differences of explosive signals can be measured. Detonations separated both temporally and spatially are considered. It is hoped this work will contribute to an understanding of the role explosive signals can play in the design of a global ATOC network.