WOCE-Argo Global Hydrographic Climatology (WAGHC Version 1.0)

Project: WOCE-Argo Global Hydrographic Climatology - The WAGHC is a full-depth one-fourth degree resolution temperature and salinity climatology describing the mean state of the World Ocean between 1996 and 2011, with monthly gridded fields available between the surface and 1778 m depth. World Ocean Database 2013 (Locarnini et al., 2013) provided the majority of the temperature and salinity profiles, whereas data from the Alfred-Wegener-Institute, Bremerhaven, and from several Canadian Institutes helped to improve the data basis for the North Polar region considerably. A rigorous data quality control procedure was applied to the original profiles to exclude erroneous and highly untypical data. The spatial interpolation of the quality-controlled data was performed both on isobaric and isopycnal levels, so that essentially two climatologies are available. The isopycnally-averaged climatology mimics the process of isopycnal mixing in the real ocean and therefore is less prone to the production of artificial water masses. The WAGHC climatology represents the update of the WOCE Global Hydrographic Climatology (Gouretski and Koltermann, 2004). The name of the new climatology was chosen to highlight both the outstanding role of the WOCE hydrographic data for the historical global hydrographic archive and the importance of the more recent data from the Argo floats. Web-link: http://icdc.cen.uni-hamburg.de/1/daten/ocean/waghc/ References: Locarnini, R. A., A. V. Mishonov, J. I. Antonov, T. P. Boyer, H. E. Garcia, O. K. Baranova, M. M. Zweng, C. R. Paver, J. R. Reagan, D. R. Johnson, M. Hamilton, D. Seidov (2013) World Ocean Atlas 2013, Volume 1: Temperature. S. Levitus, Ed., A. Mishonov Technical Ed.; NOAA Atlas NESDIS 73, 40 pp. Gouretski, V., Koltermann, K.(2004) WOCE Global Hydrographic Climatology, Berichte des BSH, 35, 52pp., ISSN: 0946-6010. Funder: The work was conducted as part of the Excellence Initiative CLISAP at the Universität Hamburg, funded through the German Science Foundation (Grant EXC 177/2) Summary: The WOCE/ARGO Global Hydrographic Climatology (WAGHC) is concieved as the update of the previous WOCE Global Hydrographic Climatology (WGHC) (Gouretski and Koltermann, 2004). The following improvements have been made compared to the WGHC: 2) finer spatial resolution (0.25 degrees Lat/Lon compared to 0.5 degrees for WGHC); 3) finer vertical resolution (65 compared to 45 WGHC standard levels); 4) monthly temporal resolution compared to the all-data-mean WGHC parameters; 5) narrower overall time period; 6) calculation of the mean year corresponding to the optimally interpolated temperature and salinity values; 7) depth of the upper mixed layer. Similar to the WGHC the optimal spatial interpolation is performed on the local isopycnal surfaces. This approach diminishes the production of the artificial water masses. In addition to the isopycnally interpolated parameters parameter values interpolated on the isobaric levels are also provided. The monthly gridded vertical profiles extend to the depth of 1898 m, below only annual mean parameter values are available. Additionally, there is a dataset and a map available providing indexes for selected regions of the world ocean. Finally, the comparison with the last update of the NOAA World Ocean Atlas (Locarnini et al, 2013) was done.