Funding is requested for a 3-year renewal of the NSF portion of the Pacific High Resolution XBT/XCTD (HRX) network. This an ocean-spanning set of repeated eddy-resolving upper ocean transects with the objective of observing interannual variability in ocean circulation and the transport of mass, heat and freshwater. The program has now nearly a decade of quarterly repeat sections. Sampling will be continued with 800-m Deep Blue XBTs plus supplemental sampling with new 2000-m T-12 XBTs to determine deep geostrophic shear in Western boundary currents and on basin-wide scales. The HRX network is an important element of the Pacific plan developed by the CLImate VARiability and predictability Program (CLIVAR). Planned analyses during the next three years will focus on basin-wide synthesis of the HRX data and comparison with results from related data assimilation and modeling efforts.
