Pacific Ocean western boundary currents and the interlinked equatorial Pacific circulation system were among the first currents of these types to be explored by pioneering oceanographers. The widely accepted but poorly quantified importance of these currents—in processes such as the El Niño/Southern Oscillation, the Pacific Decadal Oscillation and the Indonesian Throughflow—has triggered renewed interest. Ongoing efforts are seeking to understand the heat and mass balances of the equatorial Pacific, and possible changes associated with greenhouse-gas-induced climate change. Only a concerted international effort will close the observational, theoretical and technical gaps currently limiting a robust answer to these elusive questions.
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W.C. and G.W. are supported by the Australian Climate Change Science Program, a CSIRO Office of the Chief Executive Science Leader award, and CSIRO Office of the Chief Executive postdoctoral awards. L.W., Z.C. and X.L. are supported by projects (41130859,41490640, 41306001) of the National Science Foundation of China (NSFC), and a project (2013CB956200) of the National Basic Research Program of China (MOST). D.H. is supported by CAS Program XDA 11010101, and NSFC Grants 41330963 and 41421005. S.H. is supported by NSFC Grant 41406016. Q.W. is supported by MOST Grant 2013CB956202. F.W. is supported by MOST Grant 2012CB417401 and NSFC/Shangdong Grant U1406401, A.G. is supported by CNRS/INSU/LEFE project MoorSPICE. This is PMEL Contribution Number 4207, and Lamont-Doherty Earth Observatory Contribution Number 7875. J.S. is supported by the National Aeronautics and Space Administration (NASA) under award no. NNX13AO38G. Y.K. is supported by the Tropical Ocean Climate Study of Japan Agency for Marine-Earth Science and Technology. This is a contribution to the CLIVAR SPICE and NPOCE programmes. We thank A. Purich and T. Cowan for their comments before submission. We acknowledge the World Climate Research Programme’s Working Group on Coupled Modelling, and we thank the climate modelling groups for producing and making available their model output. The US Department of Energy’s Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led the development of software infrastructure in partnership with the Global Organization for Earth System Science Portals.
The authors declare no competing financial interests.
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Hu, D., Wu, L., Cai, W. et al. Pacific western boundary currents and their roles in climate. Nature 522, 299–308 (2015). https://doi.org/10.1038/nature14504
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