Collaborative Research: US GO-SHIP 2021-2026 Repeat Hydrography, Carbon and Tracers

Award Period
to
Award Amount
$1,234,606
Agency Name
National Science Foundation (NSF)
Award Number
2023500
PI First Name
Craig
PI Last Name
Carlson
MSI People
Area/s of Research
Oceanography
Abstract

The U.S. GO-SHIP Program is a systematic re-occupation of key global hydrographic sections that began

in 2003. The sections span all ocean basins and are full-depth, with physical and chemical measurements

of the highest ‘reference standard’ accuracy, attainable only with research ships for the foreseeable future.

The proposed work extends this unique climate data set over the next six years. The U.S. program is a

major contributor to the international Global Ocean Ship-based Hydrographic Investigations Program

(GO-SHIP), designed to monitor the ocean's response to climate change; GO-SHIP is part of the WCRP’s

Global Ocean Observing System.

Fourteen cruises during the period 2021-2026 are proposed, with the continuing objective of

systematically quantifying global-scale changes in storage and transport of heat, freshwater, carbon,

oxygen, nutrients, and related parameters. Four will be led by NOAA, nine by NSF/UNOLS, and one will

be joint. Proposed measurements are: hydrographic/physical (CTDO2, salinity, oxygen, nutrients, U, V

and W from LADCP, U and V from underway ADCP, underway T and S, meteorology, bathymetry),

carbon system (DIC, pCO2, TAlk, pH, DOC, TDN, underway pCO2), and transient tracers (CFCs, SF6).

U.S. GO-SHIP will continue to cooperate with separately funded investigators: examples include a newly

framed Bio-GO-SHIP program; measurement of 14C, Fe/trace metals, 3H/3He; microstructure turbulence

measurements, as well as floats and drifters. This proposal includes funds to collect data and perform

quality control to achieve reference quality, with limited synthesis support (postdocs). Data will be

released using the successful approach in place since 2003, with a stringent data policy of rapid and open

dissemination, including transfer to recognized data centers.

Intellectual Merit:

The new hydrographic data sets will continue to contribute to overlapping scientific and technical

objectives: 1) heat/freshwater storage and flux; 2) carbon system and biogeochemical studies; 3) water

mass ventilation: 4) model calibration, validation, and state estimation; and 5) autonomous sensor

calibration, including Core (2000 m T, S), Deep, and Biogeochemical Argo profiling floats. Building on

observations first made in the 1990's, this program (begun in 2003) has been critical, and remains

essential/irreplaceable, to developing our understanding of ocean-related climate changes including:

warming of the abyssal ocean that takes up ~10% of the Earth's excess heat, changes in circulation and

ventilation, increasing anthropogenic carbon uptake and its impact on global carbon budgets and

acidification, declining oxygen concentrations, and expansion of oxygen minimum zones.

Broader Impacts:

a) The U.S. GO-SHIP open data policy has resulted in rapid, widespread availability and data use. b) The

program benefits to society include the collection of a high quality, full water column data set with

(sparse) global, decadal coverage. These data are used to assess climate change by quantifying the uptake

and storage of heat, freshwater and anthropogenic CO2 by the ocean, and changes in ventilation and

oxygen distribution. These data will continue to be used to document long-term trends in heat, freshwater,

oxygen, nutrient and carbon content; they are the only globally available source of such information

below 2000 m. The data will continue to be a resource for climate model validation. c) Outreach for U.S.

GO-SHIP data collection (cruise-based) and synthesis will extend data usefulness and public awareness.

d) The program will continue to promote and seeks to expand scientific and leadership training for

graduate students, postdoctoral scientists, and early career scientists. Funds are budgeted for graduate

students, postdocs, and young scientists to participate in each cruise, and for an annual postdoc program

to entrain young scientists in use of these invaluable observations.