主流系与西太平洋暖池变异机制研究进展
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摘要
中国科学院战略性先导科技专项重点任务2以热带西太平洋主流系和暖池为主要研究对象,基于西太平洋和印尼海科学观测网综合观测数据,结合动力理论分析和数值模拟结果,在主流系和西太暖池的三维结构、变异规律和动力机制,以及西太与周围海域之间物质能量交换等方面取得了原创性成果。在上层主流系和暖池变异方面,首次直接观测到棉兰老潜流(MUC)、吕宋潜流(LUC)和北赤道潜流(NEUC)等次表层潜流及其多尺度变异,给出了三支潜流相互间的水源关系,揭示了潜流系统强劲的季节内变化特征及其与中尺度涡旋活动的关系,并进一步分析了棉兰老流(MC)/MUC年际变异及其控制因素。西太平洋主流系平流输送在暖池形成中起到了主要作用,而且暖池北部区域自20世纪90年代起出现显著的扩张现象,是由混合层厚度变浅导致。在中深层环流特征和机制方面,发现南北半球中层水团的交换通道、机制和显著交换周期;丰富了对赤道西太平洋中层流结构特征和变异的认识,同时突破了对西太平洋深层环流结构特征和变异规律的认知局限,例如中深层流流速自北向赤道增加,其变化远大于平均值,菲律宾海盆中部深层流以西南-东北方向为主,赤道区域中深层流以纬向东西交替的射流为主等。在西太与周围海域之间物质能量交换方面,通过在印尼贯穿流(ITF)源区及印尼海的同步走航及定点潜标观测,揭示了MC在苏拉威西海和马鲁古海峡交汇处的流径跃变在2015—2016超强El Ni?o的发生起重要作用,西边界流区的非线性反射对ENSO事件的发生发展起至关重要的作用。上述原创性成果显著提升了热带西太平洋环流动力学的认知水平。
One of the key task of the Strategic Priority Research Program of the Chinese Academy of Sciences entitled "Western Pacific Ocean System"(WPOS) aims at the comprehensive research into main current system and warm pool in the western Pacific. By analyzing the deep-sea observation data, WPOS has achieved significant progresses on the structure, variability, and dynamical mechanism of three-dimensional circulations in the Western Pacific, and the mass and energy exchanges between the Western Pacific Ocean and its surrounding areas. First, on the upper ocean circulations and the warm pool, we directly observed and hence confirmed the existence of subsurface undercurrents(the Mindanao Undercurrent, Luzon Undercurrent, and North Equatorial Undercurrent) east of the Philippines, clarified the relationship among the three undercurrents, and revealed the significant intraseasonal variability of them and their relationships with mesoscale eddies, and analyzed the interannual variability of MC/MUC(Mindanao Current/Mindanao Undercurrent) and its driving force. The heat advection by ocean circulations in the western pacific play important roles in the formation and maintenance of the warm pool, and the northern part of the warm pool has significantly expanded since 1990 s, which is related to the reduction of the mixed layer. Second, on the intermediate and deep ocean circulations, we explored the alternating period of intermediate waters exchange from the Northern and Southern Hemispheres, achieved a more complete understanding of the intermediate current system, and made a breakthrough in understanding the characteristic and variability of deep ocean currents. The intermediate and deep ocean velocities increase equatorward with standard deviation much larger than mean. The intermediate and deep ocean currents flowed mainly in the meridional direction in the central Philippine Basin, and were dominated by a series of alternating westward and eastward zonal jets in the Caroline Basin. I Third, on mass and energy exchanges between the western Pacific and its surrounding areas, we conducted successfully three joint cruises in the Indonesian seas and the ITF(Indonesia Throughflow) entrance area. The observations suggest that the leap transition of the MC pathway between the Sulawesi Sea and the Maluku Strait play a key role in the 2015/16 supper El Ni?o event. The nonlinearity of the western boundary current reflections is very important in the developing of ENSO.
One of the key task of the Strategic Priority Research Program of the Chinese Academy of Sciences entitled "Western Pacific Ocean System"(WPOS) aims at the comprehensive research into main current system and warm pool in the western Pacific. By analyzing the deep-sea observation data, WPOS has achieved significant progresses on the structure, variability, and dynamical mechanism of three-dimensional circulations in the Western Pacific, and the mass and energy exchanges between the Western Pacific Ocean and its surrounding areas. First, on the upper ocean circulations and the warm pool, we directly observed and hence confirmed the existence of subsurface undercurrents(the Mindanao Undercurrent, Luzon Undercurrent, and North Equatorial Undercurrent) east of the Philippines, clarified the relationship among the three undercurrents, and revealed the significant intraseasonal variability of them and their relationships with mesoscale eddies, and analyzed the interannual variability of MC/MUC(Mindanao Current/Mindanao Undercurrent) and its driving force. The heat advection by ocean circulations in the western pacific play important roles in the formation and maintenance of the warm pool, and the northern part of the warm pool has significantly expanded since 1990 s, which is related to the reduction of the mixed layer. Second, on the intermediate and deep ocean circulations, we explored the alternating period of intermediate waters exchange from the Northern and Southern Hemispheres, achieved a more complete understanding of the intermediate current system, and made a breakthrough in understanding the characteristic and variability of deep ocean currents. The intermediate and deep ocean velocities increase equatorward with standard deviation much larger than mean. The intermediate and deep ocean currents flowed mainly in the meridional direction in the central Philippine Basin, and were dominated by a series of alternating westward and eastward zonal jets in the Caroline Basin. I Third, on mass and energy exchanges between the western Pacific and its surrounding areas, we conducted successfully three joint cruises in the Indonesian seas and the ITF(Indonesia Throughflow) entrance area. The observations suggest that the leap transition of the MC pathway between the Sulawesi Sea and the Maluku Strait play a key role in the 2015/16 supper El Ni?o event. The nonlinearity of the western boundary current reflections is very important in the developing of ENSO.
引文
王凡,胡敦欣,穆穆等,2012.热带太平洋海洋环流与暖池的结构特征、变异机理和气候效应.地球科学进展,27(6):595-602
杨宇星,黄菲,王东晓,2007.印度洋-太平洋暖池的变异研究.海洋与湖沼,38(4):296-303
邱东晓,黄菲,杨宇星,2007.东印度洋-西太平洋暖池的年代际变化特征研究.中国海洋大学学报(自然科学版),37(4):525-532
赵永平,吴爱明,陈永利等,2002.西太平洋暖池的跃变及其气候效应.热带气象学报,18(4):317-326
Clarke A J,1991.On the reflection and transmission of low-frequency energy at the irregular western Pacific Ocean boundary.J Geophys Res,96(S01):3289-3305
Clement A C,Seager R,Murtugudde R,2007.Why are there tropical warm pools?J Climate,18(24):5294-5311,http://dx.doi.org/10.1175/JCLI3582.1
Cravatte S,Kessler W S,Marin F,2012.Intermediate zonal jets in the tropical Pacific Ocean observed by Argo floats.J Phys Oceanogr,42(9):1475-1485
Delcroix T,Cravatte S,and Mcphaden M J,2007.Decadal variations and trends in tropical Pacific sea surface salinity since 1970.J Geophys Res,112:C03012,http://dx.doi.org/10.1029/2006JC003801
Du Penhoat Y,Cane M A,1991.Effect of low-latitude western boundary gaps on the reflection of equatorial motions.JGeophys Res,96(S01):3307-3322
Fieux M,Molcard R,1996.Geostrophic transport of the PacificIndian Oceans throughflow.J Geophys Res,101(C5):12421-12432
Firing E,Kashino Y,Hacker P,2005.Energetic subthermocline currents observed east of Mindanao.Deep Sea Res II:Topic Stud Oceanogr,52(3-4):605-613
Firing E,1987.Deep zonal currents in the central equatorial Pacific.J Marine Research,45:791-812
Gan B L,Wu L X,2012.Possible origins of the western Pacific warm pool decadal variability.Adv Atmos Sci,29(1):169-176,http://dx.doi.org/10.1007/s00376-011-0193-6
Gordon A L,Susanto R D,Ffield A,1999.Throughflow within Makassar strait.Geophys Res Lett,26(21):3325-3328
Hirst A C,Godfrey J S,1993.The role of Indonesian Throughflow in a global ocean GCM.J Phys Oceanogr,23(6):1057-1086
Hu D X,Cui M C,1989.The western boundary current in the far western Pacific Ocean.In:Picaut J,Lukas R,Delcroix T.Western Pacific International Meeting and Workshop on Toga Coare:Proceedings.Nouméa:ORSTOM,123-134
Hu D X,Cui M C,1991.The western boundary current of the Pacific and its role in the climate.Chin J Oceanol Limnol,9(1):1-14
Hu D X,Hu S J,Wu L X et al,2013.Direct measurements of the Luzon undercurrent.J Phys Oceanogr,43(7):1417-1425
Hu D X,Wu L X,Cai W J et al,2015.Pacific western boundary currents and their roles in climate.Nature,522(7556):299-308
Hu S J,Hu D X,Guan C et al,2016.Interannual variability of the Mindanao Current/Undercurrent in direct observations and numerical simulations.J Phys Oceanogr,46(2):483-499
Kashino Y,Aoyama M,Kawano T et al,1996.The water masses between Mindanao and New Guinea.J Geophys Res,101(C5):12391-12400
Kashino Y,Ishida A,Kuroda Y,2005.Variability of the Mindanao current:Mooring observation results.Geophys Res Lett,32(18):L18611,http://dx.doi.org/10.1029/2005GL023880
Lukas R,Firing E,Hacker P et al,1991.Observations of the Mindanao current during the western equatorial Pacific Ocean circulation study.J Geophys Res,96(C4):7089-7104
Meyers G,1996.Variation of indonesian throughflow and the El Niňo-southern oscillation.J Geophys Res,101(C5):12255-12263
Molcard R,Fieux M,Syamsudin F,2001.The throughflow within Ombai Strait.Deep-Sea Res I:Oceanogr Res Papers,48(5):1237-1253
Murtugudde R,Busalacchi A J,Beauchamp J,1998.Seasonal-tointerannual effects of the Indonesian throughflow on the tropical Indo-Pacific Basin.J Geophys Res,103(C10):21425-21441
Qu T D,Kagimoto T,Yamagata T,1997.A subsurface countercurrent along the east coast of Luzon.Deep Sea Res I:Oceanogr Res Papers,44(3):413-423
Qu T D,Mitsudera H,Yamagata T,1998.On the western boundary currents in the Philippine Sea.J Geophys Res,103(C4):7537-7548
Ramanathan V,Collins W,1991.Thermodynamic regulation of ocean warming by cirrus clouds deduced from observations of the 1987 El Ni?o.Nature,351(6321):27-32,http://dx.doi.org/10.1038/351027a0
Schneider N,1998.The Indonesian Throughflow and the global climate system.J Climate,11(4):676-689
Spall M A,Pedloski J,2005.Reflection and transmission of equatorial Rossby waves.J Phys Oceanogr,35(3):363-373
Sprintall J,Gordon A L,Murtugudde R et al,2000.A semiannual Indian Ocean forced Kelvin wave observed in the Indonesian seas in May 1997.J Geophys Res,105(C7):17217-17230
Susanto R D,Gordon A L,2005.Velocity and transport of the Makassar Strait throughflow.J Geophys Res,110(C1):C01005,http://dx.doi.org/10.1029/2004JC002425
Wang F,Hu D X,1999.Preliminary study on the formation mechanism of counter western boundary undercurrents below the thermocline-A simple conceptual model.Chin JOceanol Limnol,17(1):1-9
Wang F,Hu D,Bai H,1998.Western boundary undercurrents east of the Philippines.In:Proceedings of the 4th Pacific Ocean Remote Sensing Conference(PORSEC).Qingdao:PORSEC,551-556
Wang F,Zang N,Li Y L et al,2015.On the subsurface countercurrents in the Philippine Sea.J Geophys Res Oceans,120(1):131-144
Wang F,Wang J N,Guan C et al,2016a.Mooring observations of equatorial currents in the upper 1000 m of the western Pacific Ocean during 2014.J Geophys Res,121(6):3730-3740,http://dx.doi.org/10.1002/2015JC011510
Wang F,Song L N,Li Y L et al,2016b.Semiannually alternating exchange of intermediate waters east of the Philippines.Geophys Res Lett,43(13):7059-7065,http://dx.doi.org/10.1002/2016GL069323
Wang H,Mehta V M,2008.Decadal variability of the Indo-Pacific warm pool and its association with atmospheric and oceanic variability in the NCEP-NCAR and SODAreanalyses.J Climate,21(21):5545-5565,http://dx.doi.org/10.1175/2008JCLI2049.1
Wang J N,Lu Y Y,Wang F et al,2017a.Surface current in“Hotspot”serves as a new and effective precursor for El Ni?o prediction.Sci Rep,7:166,http://dx.doi.org/10.1038/s41598-017-00244-2
Webster P J,Lukas R,1992.TOGA COARE:The coupled ocean-atmosphere response experiment.Bull Am Meter Soc,73(9):1377-1416
Wijffels S,Firing E,Toole J,1995.The mean structure and variability of the Mindanao Current at 8oN.J Geophys Res Oceans,100(C9):18421-18435
Xie L L,Tian J W,Hun D X et al,2009.A quasi-synoptic interpretation of water mass distribution and circulation in the western North PacificⅡ:Circulation.Chin J Oceanol Limnol,27(4):955-965
Yang Y X,Wang F M,2012.Northward expansion of the western Pacific Warm Pool in late 1990s and early 2000s.Chin JOceanol Limnol,30(4):684-689,http://dx.doi.org/10.1007/s00343-012-1209-5
Yuan D,Hu D,1991.Roles of the Pacific western boundary and the Mindanao current in the evolution of the equatorial“warm pool”.Mark Sci,3(4):30-32
Yuan D L,Rienecker M M,Schopf P S,2004.Long wave dynamics of the interannual variability in a numerical hindcast of the equatorial Pacific Ocean circulation during the 1990s.J Geophys Res,109(C5):C05019,http://dx.doi.org/10.1029/2003JC001936
Yuan D L,Wang J,Xu T F et al,2011.Forcing of the Indian Ocean Dipole on the interannual variations of the tropical Pacific Ocean:Roles of the indonesian throughflow.JClimate,24(14):3593-3608
Zhang L L,Hu D X,Hu S J et al,2014.Mindanao Current/Undercurrent measured by a subsurface mooring.J Geophys Res,119(6):3617-3628
Zhang L L,Wang F J,Wang Q Y et al,2017.Structure and variability of the North Equatorial Current/Undercurrent from mooring measurements at 130°E in the Western Pacific.Sci Rep,7:46310,http://dx.doi.org/10.1038/srep46310
杨宇星,黄菲,王东晓,2007.印度洋-太平洋暖池的变异研究.海洋与湖沼,38(4):296-303
邱东晓,黄菲,杨宇星,2007.东印度洋-西太平洋暖池的年代际变化特征研究.中国海洋大学学报(自然科学版),37(4):525-532
赵永平,吴爱明,陈永利等,2002.西太平洋暖池的跃变及其气候效应.热带气象学报,18(4):317-326
Clarke A J,1991.On the reflection and transmission of low-frequency energy at the irregular western Pacific Ocean boundary.J Geophys Res,96(S01):3289-3305
Clement A C,Seager R,Murtugudde R,2007.Why are there tropical warm pools?J Climate,18(24):5294-5311,http://dx.doi.org/10.1175/JCLI3582.1
Cravatte S,Kessler W S,Marin F,2012.Intermediate zonal jets in the tropical Pacific Ocean observed by Argo floats.J Phys Oceanogr,42(9):1475-1485
Delcroix T,Cravatte S,and Mcphaden M J,2007.Decadal variations and trends in tropical Pacific sea surface salinity since 1970.J Geophys Res,112:C03012,http://dx.doi.org/10.1029/2006JC003801
Du Penhoat Y,Cane M A,1991.Effect of low-latitude western boundary gaps on the reflection of equatorial motions.JGeophys Res,96(S01):3307-3322
Fieux M,Molcard R,1996.Geostrophic transport of the PacificIndian Oceans throughflow.J Geophys Res,101(C5):12421-12432
Firing E,Kashino Y,Hacker P,2005.Energetic subthermocline currents observed east of Mindanao.Deep Sea Res II:Topic Stud Oceanogr,52(3-4):605-613
Firing E,1987.Deep zonal currents in the central equatorial Pacific.J Marine Research,45:791-812
Gan B L,Wu L X,2012.Possible origins of the western Pacific warm pool decadal variability.Adv Atmos Sci,29(1):169-176,http://dx.doi.org/10.1007/s00376-011-0193-6
Gordon A L,Susanto R D,Ffield A,1999.Throughflow within Makassar strait.Geophys Res Lett,26(21):3325-3328
Hirst A C,Godfrey J S,1993.The role of Indonesian Throughflow in a global ocean GCM.J Phys Oceanogr,23(6):1057-1086
Hu D X,Cui M C,1989.The western boundary current in the far western Pacific Ocean.In:Picaut J,Lukas R,Delcroix T.Western Pacific International Meeting and Workshop on Toga Coare:Proceedings.Nouméa:ORSTOM,123-134
Hu D X,Cui M C,1991.The western boundary current of the Pacific and its role in the climate.Chin J Oceanol Limnol,9(1):1-14
Hu D X,Hu S J,Wu L X et al,2013.Direct measurements of the Luzon undercurrent.J Phys Oceanogr,43(7):1417-1425
Hu D X,Wu L X,Cai W J et al,2015.Pacific western boundary currents and their roles in climate.Nature,522(7556):299-308
Hu S J,Hu D X,Guan C et al,2016.Interannual variability of the Mindanao Current/Undercurrent in direct observations and numerical simulations.J Phys Oceanogr,46(2):483-499
Kashino Y,Aoyama M,Kawano T et al,1996.The water masses between Mindanao and New Guinea.J Geophys Res,101(C5):12391-12400
Kashino Y,Ishida A,Kuroda Y,2005.Variability of the Mindanao current:Mooring observation results.Geophys Res Lett,32(18):L18611,http://dx.doi.org/10.1029/2005GL023880
Lukas R,Firing E,Hacker P et al,1991.Observations of the Mindanao current during the western equatorial Pacific Ocean circulation study.J Geophys Res,96(C4):7089-7104
Meyers G,1996.Variation of indonesian throughflow and the El Niňo-southern oscillation.J Geophys Res,101(C5):12255-12263
Molcard R,Fieux M,Syamsudin F,2001.The throughflow within Ombai Strait.Deep-Sea Res I:Oceanogr Res Papers,48(5):1237-1253
Murtugudde R,Busalacchi A J,Beauchamp J,1998.Seasonal-tointerannual effects of the Indonesian throughflow on the tropical Indo-Pacific Basin.J Geophys Res,103(C10):21425-21441
Qu T D,Kagimoto T,Yamagata T,1997.A subsurface countercurrent along the east coast of Luzon.Deep Sea Res I:Oceanogr Res Papers,44(3):413-423
Qu T D,Mitsudera H,Yamagata T,1998.On the western boundary currents in the Philippine Sea.J Geophys Res,103(C4):7537-7548
Ramanathan V,Collins W,1991.Thermodynamic regulation of ocean warming by cirrus clouds deduced from observations of the 1987 El Ni?o.Nature,351(6321):27-32,http://dx.doi.org/10.1038/351027a0
Schneider N,1998.The Indonesian Throughflow and the global climate system.J Climate,11(4):676-689
Spall M A,Pedloski J,2005.Reflection and transmission of equatorial Rossby waves.J Phys Oceanogr,35(3):363-373
Sprintall J,Gordon A L,Murtugudde R et al,2000.A semiannual Indian Ocean forced Kelvin wave observed in the Indonesian seas in May 1997.J Geophys Res,105(C7):17217-17230
Susanto R D,Gordon A L,2005.Velocity and transport of the Makassar Strait throughflow.J Geophys Res,110(C1):C01005,http://dx.doi.org/10.1029/2004JC002425
Wang F,Hu D X,1999.Preliminary study on the formation mechanism of counter western boundary undercurrents below the thermocline-A simple conceptual model.Chin JOceanol Limnol,17(1):1-9
Wang F,Hu D,Bai H,1998.Western boundary undercurrents east of the Philippines.In:Proceedings of the 4th Pacific Ocean Remote Sensing Conference(PORSEC).Qingdao:PORSEC,551-556
Wang F,Zang N,Li Y L et al,2015.On the subsurface countercurrents in the Philippine Sea.J Geophys Res Oceans,120(1):131-144
Wang F,Wang J N,Guan C et al,2016a.Mooring observations of equatorial currents in the upper 1000 m of the western Pacific Ocean during 2014.J Geophys Res,121(6):3730-3740,http://dx.doi.org/10.1002/2015JC011510
Wang F,Song L N,Li Y L et al,2016b.Semiannually alternating exchange of intermediate waters east of the Philippines.Geophys Res Lett,43(13):7059-7065,http://dx.doi.org/10.1002/2016GL069323
Wang H,Mehta V M,2008.Decadal variability of the Indo-Pacific warm pool and its association with atmospheric and oceanic variability in the NCEP-NCAR and SODAreanalyses.J Climate,21(21):5545-5565,http://dx.doi.org/10.1175/2008JCLI2049.1
Wang J N,Lu Y Y,Wang F et al,2017a.Surface current in“Hotspot”serves as a new and effective precursor for El Ni?o prediction.Sci Rep,7:166,http://dx.doi.org/10.1038/s41598-017-00244-2
Webster P J,Lukas R,1992.TOGA COARE:The coupled ocean-atmosphere response experiment.Bull Am Meter Soc,73(9):1377-1416
Wijffels S,Firing E,Toole J,1995.The mean structure and variability of the Mindanao Current at 8oN.J Geophys Res Oceans,100(C9):18421-18435
Xie L L,Tian J W,Hun D X et al,2009.A quasi-synoptic interpretation of water mass distribution and circulation in the western North PacificⅡ:Circulation.Chin J Oceanol Limnol,27(4):955-965
Yang Y X,Wang F M,2012.Northward expansion of the western Pacific Warm Pool in late 1990s and early 2000s.Chin JOceanol Limnol,30(4):684-689,http://dx.doi.org/10.1007/s00343-012-1209-5
Yuan D,Hu D,1991.Roles of the Pacific western boundary and the Mindanao current in the evolution of the equatorial“warm pool”.Mark Sci,3(4):30-32
Yuan D L,Rienecker M M,Schopf P S,2004.Long wave dynamics of the interannual variability in a numerical hindcast of the equatorial Pacific Ocean circulation during the 1990s.J Geophys Res,109(C5):C05019,http://dx.doi.org/10.1029/2003JC001936
Yuan D L,Wang J,Xu T F et al,2011.Forcing of the Indian Ocean Dipole on the interannual variations of the tropical Pacific Ocean:Roles of the indonesian throughflow.JClimate,24(14):3593-3608
Zhang L L,Hu D X,Hu S J et al,2014.Mindanao Current/Undercurrent measured by a subsurface mooring.J Geophys Res,119(6):3617-3628
Zhang L L,Wang F J,Wang Q Y et al,2017.Structure and variability of the North Equatorial Current/Undercurrent from mooring measurements at 130°E in the Western Pacific.Sci Rep,7:46310,http://dx.doi.org/10.1038/srep46310