Comparisons of gyre-scale acoustic and direct thermal measurements
of heat content in the Pacific Ocean, satellite altimeter measurements
of sea surface height, and results from a general circulation model
show that only about half of the seasonal and year-to-year changes in
sea level are attributable to thermal expansion. Interpreting climate
change signals from fluctuations in sea level is therefore complicated.
The annual cycle of heat flux is 150 ± 25 watts per square
meter (peak-to-peak, corresponding to a 0.2°C vertically
averaged temperature cycle); an interannual change of similar magnitude
is also detected. Meteorological estimates of surface heat flux, if
accurate, require a large seasonal cycle in the advective heat flux.
The ATOC Consortium: A. B. Baggeroer, T. G. Birdsall, C. Clark, J. A. Colosi, B. D. Cornuelle, D. Costa, B. D. Dushaw, M. Dzieciuch, A. M. G. Forbes, C. Hill, B. M. Howe, J. Marshall, D. Menemenlis, J. A. Mercer, K. Metzger, W. Munk, R. C. Spindel, D. Stammer, P. F. Worcester, and C. Wunsch.* A. B. Baggeroer is in the Department of Ocean
Engineering, Massachusetts Institute of Technology (MIT),
Cambridge, MA 02139, USA. T. G. Birdsall and K. Metzger are
in the Department of Electrical Engineering and Computer Sciences,
University of Michigan, Ann Arbor, MI 48109, USA. C. Clark is in
the Laboratory of Ornithology, Cornell University, Ithaca, NY 14853, USA. J. A. Colosi is in the Department of Applied Ocean
Physics and Engineering, Woods Hole Oceanographic Institution, Woods
Hole, MA 02543, USA. B. D. Cornuelle, M. Dzieciuch, W. Munk,
and P. F. Worcester are at Scripps Institution of Oceanography,
University of California, San Diego, La Jolla, CA 92093, USA. D. Costa is in the Biology Department, University of California, Santa
Cruz, CA 95064, USA. B. D. Dushaw, B. M. Howe, J. A. Mercer, and R. C. Spindel are at the Applied Physics
Laboratory, University of Washington, Seattle, WA 98105, USA.
A. M. G. Forbes is at the Division of Oceanography, CSIRO,
Hobart, Tasmania 7001, Australia. C. Hill, J. Marshall, D. Menemenlis,
D. Stammer, and C. Wunsch are in the Department of Earth, Atmospheric
and Planetary Sciences, MIT, Cambridge, MA 02139, USA.
