Collaborative Research: Global Ocean Repeat Hydrography, Carbon, and Tracer Measurements, 2015-2020

Lead PI: Andreas M. Thurnherr , Mr. Bruce A. Huber , Ms. Victoria Nazario , Lynne Talley, James Swift

Unit Affiliation: Ocean and Climate Physics, Lamont-Doherty Earth Observatory (LDEO)

March 2015 - February 2023
Project Type: Research

DESCRIPTION: Earth's climate is changing, with large natural decadal variability in some regions. Among the most important and basic climate system components are the heat, freshwater, and carbon content and transport of the oceans, which directly interact with other essential components of the climate system in the atmosphere and cryosphere. In turn the associated variability and trends in the ocean's carbon content, carbonate saturation state, oxygen, and nutrients impact its internal biological environment, with notable large-scale regional changes. This joint study of the ocean carbon cycle and circulation is critical to identify critical areas where changes in ocean circulation could have serious consequences for future anthropogenic carbon uptake. Global warming-induced changes in the ocean's transport of heat and freshwater, which could affect the circulation, are being followed through these long-term measurements. Results to date have shown that the abyssal ocean is warming, taking up to 30% of the excess heat in the entire Earth system, leading to changes in circulation patterns and ventilation rates in the upper ocean. The uptake of anthropogenic carbon from the atmosphere to the ocean has been mapped and shows that the oceans are acidifying. Oxygen concentrations are declining in the ocean thermocline, and tropical oxygen minimum zones are expanding. The project is based on the fundamental concept that data collected belong to the community and need to be made quickly and freely available to the community at large through a recognized international data center. The project will continue to promote training and learning for graduate students, postdoctoral scientists, and new scientists in sea-going work. Outreach activities will continue as opportunities arise.


University of California, San Diego


National Science Foundation




Shuwen Tan


University of California, San Diego