Part 1: Abstract of the Project

Abstract

The 3-D characteristics of ocean circulation were revealed in the low latitude westernboundary region in the late 1980s, when some undercurrents were discovered. A 3-Dcirculation theory is needed as the classical 2-D theory has been not able to describethe three dimensional circulation structure. The warm pool variability is of importanceto prediction of ENSO, monsoon and summer draughts and floods in China. A peopleconcerned problem is how important is thee low latitude western boundary currents in thePacific plays in formation and evolution of the role warm pool. However, one does notreally know the three dimensional structure of the ocean circulation in this region.Through available data analysis, key observations numerical modeling and theoreticalanalysis, three dimensional characteristics and its variability mechanism will beclearly expounded, a 3-D dynamical theory on LLWG circulation system will be developedand the role of the circulation will be clarified in the formation and low frequencyvariability of the warm pool. Break-throughs are expected to be made in these respects,to provide solid ocean dynamics base for prediction ENSO and east Asian monsoon. Theresearch is of great scientific and practical significance to ocean dynamics and climatedynamics.

Part 2. Progress of the Project

The kick-off meeting for themajor project"Studies on the low-latitude western boundary current system in the west Pacific Ocean and low-frequency variation of the Warm Pool", funded by National Natural Science Foundation of China(NSFC), is held in Qingdao on February 13, 2009. The principal investigator (PI) of this project is Dunxin Hu, academician of Chinese Academy of Sciences.

Yucheng Chai from NSFC, vice president Xu Chang of Bureau of Science and Technology for Resources and Environment, Jilan Su and Dake Chen from the Second Institute of Oceanography, SOA, Academician Mu Mu of IAP, President Dexing Wu from Ocean University of China, Professor Zhaobo Sun from Nanjing University of Science & Technology were present in the meeting. Many other experts and representatives, coming from National Oceanographic Center, Qingdao, Qingdao Municipal Science and Technology Commission, Ocean University of China, Institute of Applied Physics and Computational Mathematics, Guangzhou University, University of Science and Technology of China, Guangdong Ocean University, also attended

Academician Dunxin Hu issued the engagement letter to the members of the academicexperts, and introduced the project's background. Each sub-projectPIs reported the research contents, expected targets, implementation plans of the program. The research plan was discussed and many valuable suggestions and comments were put forward.

Workshopfor this NSFC major project was held at Qingdao on May 5th, 2009. The meeting was chaired by Academician Dunxin Hu of IOCAS. The sub-project PIs,"Tai-Shan Scholars" researcher Fei Yu and other key members participated in the meeting. Each sub-project team reported about the progress on data analysis, numerical simulation, theoretical work,and so on.Special discussions were focused on two difficult key problems. The meeting had achieved a great success.Asolid foundation was laid for the implementation of the project.

Deep-sea observation, at about depth of 5000-9000 meters in the Western Pacific by the submersible mooring, is one of the core issues at the NSFC major project.For this reason, five researchers, leaded by Academician Dunxin Hu, made a special visit to Japan Agency for Marine-Earth Science and Technology (JAMSTEC) and the University of Tokyo,from June 29 to July 4, 2009.

During this visit, the delegation introduced the current situation and plans of China's research programson Western Pacific Oceancirculation and climate to the Japanese,and the Japanese also presented their current situation and plans onthis area, in particular, shared their experience in deep-seaobservation by submersible mooring. This visit deepenedthe friendship and understandingsbetween the two states.

In JAMSTEC，Academician Dunxin Hu talked to Dr Imawaki and Dr Mizuno. He described the NPOCE (Northwestern Pacific Ocean Circulation Experiment) project proposed by China，including other programs in the western Pacific Ocean. Dr Imawaki talked about the recently observation plans and current situation in JAMSTEC, and expressed that the cooperation should be strengthened in scientific between the two states. At the submersible mooring technology exchange meeting，the design and launching of the submersible mooring were discussed. In the meeting for exchange of scientific, Academician Dunxin Hu, Professor Fan Wang and Jiwei Tian gave lectures on “Introduction to NPOCE”，“Subsurface countercurrents beneath the thermocline in the Western Pacific Ocean”，“Enhanced mixing in the South China Sea”, respectively. The Japanese researchers show much interest in these topics. And JAMSTEC researchers also show their new observed results, giving us much great valuable advice in the designing, launching and recycling of the submersible mooring. They also kindly provided us some observational data.

In the University of Tokyo, the delegation and Professor Yamagata, Minister of Science,as well as his research group conduct academic exchanges and talks. Academician Dunxin Hu, Researcher Fan Wang, Professor Jiwei Tian, and the team of Professor Yamagata, introduced the latest scientific results, respectively. Through the talks, both sides hoped to make deeply cooperation, and discussed matters related to the framework and specific details of cooperation.

The delegation completed the scheduled 5-day visit to Japan successfully. It is a key issue about implementing technical policy of the major NFSC project.Meanwhile, the study tour reviewed and strengthened the friendship and cooperation between China and Japan on the study areas at ocean circulation and climate, particular in the Western Pacific, layinga foundation for cooperation in the future.