Between 1990 and 1998 the WOCE Hydrographic Programme (WHP) occupied a grid of 20000 full depth hydrographic stations (the WHP One Time Survey). Together with other occupations of some of these sections (repeat hydrography), these sections document changes in oceanic properties and circulation on decadal timescales based on physical, chemical and transient tracer measurements. They also form the basis for determining oceanic heat and freshwater transports. During the WHP, collaboration between WOCE and JGOFS led to the complementary measurement of parameters to enable ocean carbon storage and transports to be determined.

CLIVAR is concerned with further refining WOCE determinations of oceanic heat and freshwater transports and with documenting decadal and shorter period ocean changes based in large part on the reoccupation of a subset of the hydrographic sections that formed the WHP.

In similar fashion there are a number of national and international initiatives aimed at better assessing the role of the oceans in storing and distributing carbon, particularly in light of rapidly rising atmospheric CO2 levels. Reoccupations of WHP sections form a key component of these ocean carbon strategies. The International Ocean Carbon Coordination Project (IOCCP) is co-sponsored by the SCOR/IOC CO2 panel and the Global Carbon Project. It has been set up to work with national, regional and international carbon programs and data centres to provide a global view of ocean carbon.

Thus the reoccupations need to be closely co-ordinated between CLIVAR and the IOCCP to ensure:

1. that the essential suite of measurements are made to serve both CLIVAR and ocean carbon requirements

2. that agreed standards are set for the determination of each parameter

3. that an effective system is developed to quality-control, safeguard, distribute and archive the resulting data sets.

The figure and tables on the following pages have been compiled by the International CLIVAR Project Office (ICPO).

Links to cruise information and data:

CLIVAR repeat cruise database - please visit and update our records of cruises since 1998 and those in the planning.

CLIVAR/Carbon Hydrographic Data Office (CCHDO) - holds details of cruises and hydrographic data from the WOCE Project (1988-1998).

The International Ocean Carbon Coordination Project (IOCCP) hydrographic programme pages - provide details of planned ocean carbon measurements.