International Comprehensive Ocean-Atmosphere Data Set (ICOADS) Release 3.0 - Monthly Summary Groups (MSG)

This dataset, the International Comprehensive Ocean-Atmosphere Data Set (ICOADS), is the most widely-used freely available collection of surface marine observations, with over 455 million individual marine reports spanning 1662-2014-each containing the observations and metadata reported from a given ship, buoy, coastal platform, or oceanographic instrument, providing data for the construction of gridded analyses of sea surface temperature, estimates of air-sea interaction and other meteorological variables. ICOADS observations are assimilated into all major atmospheric, oceanic and coupled reanalyses, further widening its impact. R3.0 therefore includes changes designed to enable effective exchange of information describing data quality between ICOADS, reanalysis centres, data set developers, scientists and the public. These user-driven innovations include the assignment of a unique identifier (UID) to each marine report-to enable tracing of observations, linking with reports and improved data sharing. Other revisions and extensions of the ICOADS' International Maritime Meteorological Archive (IMMA) common data format incorporate new near-surface oceanographic data elements and cloud parameters. Many new input data sources have been assembled, and updates and improvements to existing data sources, or removal of erroneous data, made. The ICOADS Monthly Summaries Group (MSG) are designed to store both 1-degree, and 2-degree, latitude x longitude monthly summaries (the format also has the capability, unused at present, to store 0.5-degree data). MSG products are currently available covering the global domain (1-degree and/or 2-degree boxes) and an equatorial domain (1-degree), with 2-degree products available from 1800 forward and 1-degree products available only for 1960 forward. Six "groups" of variables make up MSG. The variables comprise the 19 variables that were produced for COADS Release 1 (groups 3-7) plus three additional variables that make up group 9: the cube of the wind speed, W**3, as well as the zonal and meridional contributions to the latent heat flux, U(QS-Q) and V(QS-Q).