John L. Spiesberger
Woods Hole Oceanogr. Inst., Woods Hole, MA 02543
Acoustic tomography data from a 3000-km section in the northeast Pacific are consistent with Del Grosso's algorithm for the speed of sound in seawater [J. Acoust. Soc. Am. 56, 1084--1091 (1974)] given reasonable assumptions concerning acoustic propagation and thermal variability in the ocean. Because tomographic derivations for the algorithm are sensitive to modeling assumptions, the accuracy of Del Grosso's algorithm is difficult to test without more data.