Dave Mellinger
Fri, 12 Apr 2002 08:04:12 -0700
This is forwarded on behalf of Rex Andrew, [EMAIL PROTECTED] Please reply to him, not to me. -Dave Mellinger ------------------------------------------------------------
Dear Colleague, We would like to draw your attention to our article, "Ocean ambient sound: Comparing the 1960s with the 1990s for a receiver off the California coast", by Andrew, Howe, Mercer and Dzieciuch, which you may find of interest. We were able to compare ambient noise levels measured at Pt. Sur in the 1990s (by us) and in the 1960s (by Wenz) and generally found an increase of up to 10 dB, particularly in the "shipping" bands. The article is available online from the electronic journal Acoustics Research Letters Online (ARLO) at URL: http://ojps.aip.org/ARLO/main.jsp Navigate to the April 2002 issue (vol. 3, issue 2). Alternatively, this URL should take you directly to the contents webpage from which you can download the PDF of GZipped Postscript file: http://ojps.aip.org/journal_cgi/dbt?KEY=ARLOFJ&Volume=3&Issue=2 The abstract is appended below. Sincerely, Rex K. Andrew Applied Physics Laboratory Seattle, WA ***** ABSTRACT ***** Ocean ambient sound data from 1994 to 2001 have been collected using a receiver on the continental slope off Point Sur, California. A temporary, nearby receiving array was used for calibration purposes. The resulting data set is compared with long-term averages of earlier measurements made with the identical receiver over the period from 1963 to 1965. This comparison shows that the 1994 to 2001 levels exceed the 1963 to 1965 levels by about 10 dB between 20 and 80 Hz and between 200 and 300 Hz, and about 3 dB at 100 Hz. Increases in (distant) shipping sound levels may account for this. ------------------------- Rex K. Andrew [EMAIL PROTECTED] Applied Physics Laboratory 206.543.1250 University of Washington 206.543.6785 (FAX) Seattle, Washington, USA http://staff.washington.edu/rxandrew