19^th International CODATA Conference
Category: Knowledge Discovery

Using the World Ocean Database 2001 to estimate decadal changes in heat content and freshwater budget for the world ocean

Tim Boyer (boyer@nodc.noaa.gov)
Ocean Climate Laboratory/National Oceanographic Data Center, USA

The World Ocean Database 2001 (WOD01) was released in 2001 as part of the Global Ocean Data Archeology and Rescue (GODAR) project.  It contains 7 million temperature profiles and 2 million salinity profiles from all parts of the world ocean from the mid-1800s to July, 2001. The data is available on CD as well as a constantly updated version online.  All temperature and salinity data on WOD01 have been quality controlled through a rigorous procedure which includes using the data to calculate climatologies over various time periods (annual, seasonal, monthly).  For periods with sufficient geographic coverage, 1945 to present for temperature, 1950 to present for salinity, five year mean differences from the climatologcal monthly means where calculated, removing the annual cycle.  The results were investigated to estimate decadal changes in heat content and freshwater budgets globally. The use of the WOD01 data in scientific research provided quality control of data and the discovery of problems which were not detected during prior quality control steps.  This additional quality control was passed on in quality control flags included with the data.  Our results show a nety warming of the world ocean in the upper 3000 meters. The subtropical and tropical north Atlantic having been becoming more saline, while the subpolar gyre of the north Atlantic has been getting fresher.  The north Pacific has also been freshening.