36 9 Vol.36,No.9 2014 9 ACTA OCEANOLOGICASINICA September2014. [J].,2014,36(9):94 102,doi:10.3969/j.issn. 0253-4193.2014.09.011 ZhangXu,ChengChen,LiuYan.AcousticpropagationefectcausedbysubtropicalmodewaterofnorthwesternPacific[J].Acta OceanologicaSinica(inChinese),2014,36(9):94 102,doi:10.3969/j.issn.0253-4193.2014.09.011 1,2 1 1 (1. 91550 116023;2.92493 116023) : Argo (STMW),STMW STMW 10~15dB( 1000 Hz) STMW, 20m, 6.6km; 150m 3.1km, : ; ; ;Argo;BELLHOP :P733.2 :A :0253-4193(2014)09-0094-09 1 (STMW) Ma- suzawa, 16~18 [1-3] [4] [5-6] [12] STMW, [7] 30 ~34 N,140 ~170 E [13-14] STMW, [15] - [16-18], Hanawa Taley 2000 [19], Argo [8-11], STMW :2013-06-15; :2013-12-14 : (1982 )
9 : 95 STMW,Oka 1 1 [20] Qiu 0~5500m 33 [23-24] STMW, WOA09 Argo [25] STMW Mackenzie 10m Argo, Argo c 2 A (z) WOA09 c W (z) 2.1 Z U,Argo WOA09 (NODC) Argo [21] 0~2000m 3 3, 10d [22] ST- MW STMW ( [20]) 5 10 Argo 29 ~34 N 150 ~160 E 2006-2012 2322 ( 1) k A (z) k W (z) : c A (z), 烄 z <Z U, k A (z) c A (z)+ c= (1) 烅 k W (z) c W (z) Z U z Z D, 烆 c W (z ) z >Z D, k W (z)= z-zu, (3) Z D -Z U, Z U 900~1100mArgo Z D 2000m (1)~(3) Argo WOA09 ; 1 Argo Fig.1 Theselectedregioninthispaperandthe WOA09 distributionoftheprofilers position [20] STMW, 2.3 [26],KBF:,KEF: BELLHOP,NSTF: ShadowdenotesSTMW sourcearea,rectangleareaisregion, pointsdenoteprofilers position,kbf:kuroshiobifurcatefront, KEF:Kuroshioextendedfront,NSTF:northsubtropicalfront Argo Z D ZD -z k A (z)=, (2) Z D -Z U ( Kraken) ( MMPE) 2.2 Argo 2000m Porter BELLHOP WOA09 Argo WOA09 (NODC) 1900- [26-28] : 2009 Levitus 5 m 0.2
96 36 km 1kHz; -90 ~90, 0.5 3 2 2006-2012 Argo,,, ( ) 3 0.05s -1 2, [15] ( ) 2 3 ( 200, m ) [15] ;, 2 Fig.2 TimeseriesofverticaldistributionofsoundspeedofSTMW sourcearea 2006-2012 29 ~34 N,150 ~160 E; Theabscissaaxisisfrom2006to2012,theregionisin29 ~34 N,150 ~160 E,andthepointlinesdenote thedepthrangeofweaksoundspeedgradsinsubsurfacelayer 4~7 STMW 2 5 8 11 20m BELLHOP, 20m 150m ; 4 WOA09 (1)~(3) 8
9 : 97 3 Fig.3 ProfilesofmonthlymeanofsoundspeedofSTMW sourcearea ( 8) ( 8a) 10~15dB( ) 150m,,,, 6.6, km, [29-30], SOFAR ( ( 8b), 1.0 ) ( 8), km 10dB( ) 3.1km 20m, 1-20m 150,, m,
98 36 4 2 Fig4 TypicalsoundfieldofSTMW sourceareainfebruary 5 5 Fig5 TypicalsoundfieldofSTMW sourceareain May 6 8 Fig6 TypicalsoundfieldofSTMW sourceareainaugust 7 11 Fig7 TypicalsoundfieldofSTMW sourceareainnovember
9 : 99 8 Fig.8 Comparisonofsoundtransmissionlosscurveamongdiferentmonths 1 - Tab.1 ComparisonofCZpositionwithtwodiferentsource-receiverconditions 20m 20m 150m 150m /km /km /km /km 57.3 114.4 57.3 114.3 60.5 120.0 60.6 121.2 63.9 126.7 60.8 121.5 62.8 125.7 62.6 124.0 9 Fig.9 Comparisonofraytracingpaternbetweenthesurfaceductinthewinterandthatinthesummer 5 ; STMW 9
100 36, ( 1kHz), (2) STMW [31-32], 20m, ( 6.6km ) [33] ; 150 [34-35] m,stmw 3.1km ( (STMW) Argo ), 6 : 10~15dB (1) STMW - ; Argo ; STMW,,, : [1] SugaT,HanawaK.ThemixedlayerclimatologyinthenorthwesternpartoftheNorthPacificsubtropicalgyreandtheformationareaofsubtropi- calmodewater[j].jmarres,1990,48(3):543-566. [2] Bingham F M,SugaT.DistributionsofmixedlayerpropertiesinNorthPacificwatermassformationareas:comparisonofArgofloatsand World OceanAtlas2001[J].OceanSci,2006,2(1):61-70. [3] OhnoY,IwasakaN,KobashiF,etal.MixedlayerdepthclimatologyoftheNorthPacificbasedonArgoobservations[J].JOceanogr,2009,65 (1):1-16. [4]. [J].,2009,28(4):17-26. [5] Munk W H,ForbesA M G.Globaloceanwarmin:anacousticmeasure[J].JPhysOceanogr,1989,19:1765-1778. [6]. [J].,1995,17(3):110-117. [7]. [J].,2009,28(6):23-34. [8] HenrickRF,Seigmann W L,Jacobson MJ.Generalanalysisofoceaneddyefectsforsoundtransmissionapplications[J].JAcoustSocAm, 1977,62(4):860-870. [9] HenrickRF,Burkom H S.Theefectofrangedependenceonacousticpropagationinaconvergencezoneenvironment[J].JAcoustSocAm, 1983,73(1):173-182. [10]. [J].,2006,24(2):166-172. [11]. [J].,2011,29(2):83-91. [12] MasuzawaJ.Subtropicalmodewater[J].Deep-SeaRes,1969,16:463-472. [13] Bingham F M.FormationandspreadingofsubtropicalmodewaterintheNorthPacific[J].JGeophysRes,1992,97(C7):11177-11189.
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102 36 summer.twotypesofductpropagationshowaninversepaternofsoundenergydistribution,andthediference canbearound10to15dbbetweentheinternalandtheexternaloftheduct(soundfrequencyis1khz).seasonal transitionofstmwcanalsoleadtothechangeofczpositions.thechangesareinfluencedbythesourcedepth. Whenthesourcelocatesat20 m,theczpositionreachesitsfurthestinthesummer,remainsmediuminthe spring,andarivesitsnearestinthewinter,wherethemaximumdiferencecanbe6.6km.whenthesourcelo- catesat150m,theczreduces3.1kminsummerandshowsnodistinctchangesinotherseasons. Keywords:modewater;northwesternPacific;subsurfaceduct;Argo;BELLHOP model