The International Comprehensive Ocean-Atmosphere Data Set (ICOADS Release 2.5)

ICOADS is maintained as a cooperative effort between NSF's National Center for Atmospheric Research (NCAR) and the National Oceanic and Atmospheric Administration (NOAA): specifically its Earth System Research Laboratory (ESRL), in conjunction with the Cooperative Institute for Research in Environmental Sciences (CIRES) of the University of Colorado, and its National Climatic Data Center (NCDC). Development is shared by these founding partners and very importantly numerous international collaborators.

Release 2.5 ICOADS is a major update (covering 1662-2007) of the world's most extensive surface marine meteorological data collection. Many new and improved datasets have been brought together, processed into a uniform format, and combined with the previous Release 2.4. The new data range from early non-instrumental ship observations, to measurements initiated in the 20th century from buoys and other automated platform types. Over the full period of record, spatial and temporal coverage have been enriched and data and metadata quality have been improved.

Coincident with R2.5, ICOADS is extended to near-real-time based on the best available GTS receipts (currently the real-time data received and processed by NCEP). This forward extension to ICOADS is updated monthly and lags real-time by two to six weeks. These data are subjected to basic quality checks and to the maximum extent possible the data fields are populated.

The processing and quality controlled observed data are used to create year-month summary products for 2° latitude × 2° longitude (since 1800) and 1°×1° boxes (since 1960). The monthly summary data are not analyzed or interpolated to create globally complete grids, i.e. data voids exist in the early periods of record and in remote regions where sample doesn't regularly occur.

All the data access option from the three ICOADS partners are described on the ICOADS website. This website also has a broad collection of project metadata (contact points, publications, related meetings and events, and documentation). The access connections at NCAR are described below.

National Center for Atmospheric Research (NCAR)

• Access to Individual Observation files in IMMA format and to an interface that offers user specified temporal, spatial, and parameter selection and sub-setting with ASCII text output.
• Access to Monthly Summary Statistics files in binary format and to an interface that offers user specified temporal, spatial, and parameter selection and sub-setting with ASCII text output.