Description of the CLIWOC database

We developed a user-friendly database with the 1750-1854 CLIWOC data, which is suitable to be integrated with the ICOADS database. The meteorological content focuses on wind direction and wind speed. The data, stored in the IMMA format, are accessible in numerical and in their original descriptive forms. Apart from alphanumerical meteorological information, the database contains a considerable number of images of logbook pages, and nautical information relevant to historians. The construction of the database involved a number of difficulties, including language, unit conversion, terminology and zero meridian problems. We believe that this publicly accessible database can give an important contribution to the understanding of low-frequency climate variability, as it extends the current climatological ocean databases by more than a century and probes deep into the pre-industrial era.