Downloaded from orbit.dtu.dk on: Dec 17, 2017 Temporal integration of loudness as a function of level Florentine, Mary; Buus, Søren; Poulsen, Torben Published in: Acoustical Society of America. Journal Link to article, DOI: 10.1121/1.411567 Publication date: 1996 Document Version Publisher's PDF, also known as Version of record Link back to DTU Orbit Citation (APA): Florentine, M., Buus, S., & Poulsen, T. (1996). Temporal integration of loudness as a function of level. Acoustical Society of America. Journal, 99(3), 1633-1644. 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PROGRAM OF The 129th Meeting of the AcousticalSociety of America RenaissanceWashington, DC Hotel ©Washington, DC ©30 May-3 June 1995 NOTE: All Journalarticles and Letters to the Editorare peerreviewed before publication. Program abstracts,however, are not reviewedbefore publication, since we areprohibited by time andschedule. TUESDAY MORNING, 30 MAY 1995 RENAISSANCE WEST A, 8:00 A.M. TO 12:00 NOON SeSsionlaAO AcousticalOceanography: Ocean Acoustic Tomography: Observing the Oceanin the 1990sI Walter Munk, Cochair ScrippsInstitution of Oceanography,University of California,San Diego, La Jolla,California 92093 Brian D. Dushaw, Cochair AppliedPhysics Laboratory, University of Washington,Seattle, Washington 98105 Chair's Introduction4:00 Invited Paper 8:05 laAO1.Acoustic thermometry of oceanclimate (ATOC). WalterH. Munk (ScrippsInst. of Oceanog.,IGPP-0225, UCSD, La Jolla, CA 92093) The rockyroad followed in the 1990sleading to thepresent status of acousticthermometry of oceanclimate (ATOC) will be reviewed. ContributedPapers 8:30 to 10 000 km distantduring the Acoustic Engineering Test of theAcoustic Thermometryof OceanClimate (ATOC) Program.The sourcewas sus- laAO2. A comparison of measured and predicted broadband acousticarrival patterus out to 10-Mm range during the ATOC pendedfor 7 daysduring November 1994 near the depthof the sound Acoustic Engineering Test. Brace M. Howe, Brian D. Dushaw, James channelaxis (about 650 m) in waterover 4000 m deep,in orderto avoid A. Mercer,Robert I. Odom,Robert C. Spindel(Appl. Phys. Lab., Univ. of near-sourcebottom interactions.The sourcetransmitted a phase-coded Washington,Seattle, WA 98105), Peter F. Worcester,John Colosi, m-sequencewith a centerfrequency of 75 Hz anda digit lengthof 27 ms BraceD. Comuelle,Matthew Dzieciuch (Scripps Inst. of Oceanog.,Univ. [Metzgetet al., this m•eting].Measured receptions on five bottom- of Californiaat San Diego, La Jolla,CA 92093), Arthur B. Baggeroer mountedSOSUS receiversat rangesfrom 300-4000 kin, on two vertical (MIT, Cambridge,MA 02139), Ted Birdsall,Kurt Metzger (Univ. of line array receiversat ranges of 90 and 3300 km, and on a Sohobuoy Michigan, Ann Arbor, MI 48109), Gary Bold, Sze Tan, Chris Tindle modified to have the hydrophoneon the soundchannel axis at about (Univ. of Auckland, Auckland, New Zealand), and Michael Guthrie 10 000-kin range,are compared with ray theoretic,adiabatic normal mode, (DefenseScientific Establishment, Auckland, New Zealand) and broadbandparabolic equation predictions. [Work supportedby the A low-frequencyacoustic source suspended from R/P FLIP approxi- StrategicEnvironmental Research and DevelopmentProgram through mately340 nauticalmiles WSW of San Diego transmittedto receivers90 ARPA.] 3233 J. Acoust.Soc. Am., Vol. 97, No. 5, Pt. 2, May 1995 129th Meeting:Acoustical Society of America 3233 Downloaded 27 Jun 2010 to 192.38.67.112. Redistribution subject to ASA license or copyright; see http://asadl.org/journals/doc/ASALIB-home/info/terms.jsp 8:45 9:30 '; laAO3.Signal generation andproceSSing forthe R/P Flip ATOC laAO6. Are faster than predicted arrival times seeingArctic Ocean transmissions.Kurt Metzget and Ted Birdsall(CSPL, Univ. of warming?Peter N. Mikhalevsky(Sci. Appl. Intl. Corp.,McLean, VA Michigan,Ann Arbor, MI 48109-2122) 22102), AlexanderGayalloy (Andreev Inst. of Acoust.,Moscow, Russia), and ArthurB. Baggeroer(MIT, Cambridge,MA 02139) Thewaveforms transmitted during the November 1994 Acoustic Ther- Arrivaltimes of M sequencestransmitted across the Arctic in thespring mometryofOcean Climate (ATOC) project R/P Flip measu,rement usedan of 1994during the trans-Arctic acoustic propagation (TAP) experiment [P. m-sequencephase modulated 75-Hz carrier,two cardercycles per digit. N. Mikhalevsky,J.Acoust. Soc. Am. 95, 2851(A) (1994)] are faster than Because the soume had an inherent Q of 5, the drive waveform was modeledarrival times usinghistorical climatology. The modal dependence modifiedin orderto producea twocycle. per digit outputß This paper of the traveltimes appears to be consistentwith a warmingof the Atlantic describesthe basic characteristicsof the soume,the procedureused to intermediatewater (AIW) in the Arctic Ocean. Calculationsof the effects broadenthe sourcebandwidth, the enforcementof a soumepeak power of thistype of climatechange signal, as well as ambientvariability on the limit, and showsthe resultingwaveforms. The receivedwaveforms pos- modalarrival times, will be presented.The possibilitythat the TAP results sessedsmall amounts of Doppler"shift" caused by'the motion of Flip on areconsistent with newreports of AIW warmingin theArctic [Carmack its mooring.Doppler limits the amount of timeover which receptions can et al., Geophys.Res. Lett. (in press)and K. Aagaardand E. C. Carmack, be integrated.Doppler normally must be treatedas time compression/ Science266 (23 December1994)] will be discussed.[Work supported by expansion.However, if the Doppler is sufficiently small it canbe treated as ONR, ARPA,and the Ministry of Science,Russian Federation.] simpletime shift.This paper compares the results of usingboth approaches to accountfor themotion of Flip. [WorksupPorted by the StrategicEnvi- ronmentalResearch and Development Program through ARPA.] 9:45 laAO7. Long-distancelow-frequency modal propagation into the 9:00 Lincoln Sea.Rich Pawlowicz(Instl of OceanSci., P.O. Box 6000, Sidney,BC V8L 4B2, Canada),David M. Farmer(Inst. of OceanSci., laAO4.The response of acousticmeaSurements to anthropogenic Sidney,BC V8L 4B2, Canada),Barbara Sotirin (NCCOSC-RDTE, San climatechange. Matthew A. Dzieciuch(Scripps Inst. of Oceanog., Diego, CA 92152-5000), and Slobran Sozard(Univ. of Victoria, IGPP-0225,UCSD, La Jolla,CA 92093) Victoria,BC, Canada) AnthropogenicCO2 in the atmosphereis expectedto result in in- One-Mm transmissionsfrom the April 1994 trans-Arctic acoustic creasedocean heating. The output of a coupledocean-atmospher• general propagation(TAp) experiment recorded bya verticalline array deployed circulationmodel was used tO simulateto expectedclimate changesce- from an icecampat the edgeof the continentalshelf in the Lincoln Sea are nario.The model was mn with no CO2 increase and with CO•2 doubling. analyzed.The [eceived phase is astonishinglystable, and appears to vary mainly with source/receivermotions. Travel times determinedfrom The spatialproperties of the CO2 signal are nonuniformand show that M-sequencetransmissions are less stable and are not consistentwith the heatingis not confinedto the oceansurface. The ambientclimate variabil- phasemeasurements. Modal decompositionshows that bottom effects strip ity showsa differentspatial structure that is moreemphasized at the sur- face.The GCM output was then used as an input to an acoustic propaga- out the higher-ordermodes as soundpropagates onto the shelf.The am- plitudeof the surface4rappedfirst mode is alsoweaker than predicted by tion model. The acoustictime seriescan then be analyzedfor climatic trends.The control mn is used to estimate the ambient noise processes on standardloss mechanisms. Some implications of this analysisfor the de- sign of future Arctic low-frequencytomography experiments are dis- long-termscales. Maps of the anthropogenicsignal to the ambientnoise cussed. ratio of the climatesystem can thenbe constructed.Acoustic thermometry measuresintegrals of heat contentthrough these maps. A network of sourcesand receiverscan then be designedto efficientlymonitor anthro- pogenicclimate change. Work is in progressto comparethe efficiencyof 10:00-10:15 Break different measurementsystems such as satellitealtimeters, drifters, and traditionalmeasurements to that of acousticthermometry. 10:15 9:15 laAO8.Use of simplifiedcoupled mode propagation for the laAOS.Stochastic modeling and global warming trend extraction prediction of impulse responses of megameter trans-Arctic propagation paths. Herbert A. Freese(Sci. Applic. Int. Corporation, for ocean acoustictravel times. StevenBottone (Mission Res. Corp., McLean, VA 22102) P.O. Drawer719, SantaBarbara, CA 93102-0719),Henry L. Gray,and WayneA. Woodward(Southern Methodist Univ., Dallas,TX 75275) In the springof 1994, a long-rangepropagation experiment was con- ductedin theArctic during