Ship logbooks help analyze pre-instrumental climate
The Climatological Database for the Worlds Oceans: 17501854 (CLIWOC) project, which concluded in 2004, abstracted more than 280,000 daily weather observations from ships logbooks from British, Dutch, French, and Spanish naval vessels engaged in imperial business in the eighteenth and nineteenth centuries.These data, now compiled into a database, provide valuable information for the reconstruction of oceanic wind field patterns for this key period that precedes the time in which anthropogenic influences on climate became evident. These reconstructions, in turn, provide evidence for such phenomena as the El NiñoSouthern Oscillation and the North Atlantic Oscillation. Of equal importance is the finding that the CLIWOC databasethe first coordinated attempt to harness the scientific potential of this resource [García-Herrera et al., 2005]represents less than 10 percent of the volume of data currently known to reside in this important but hitherto neglected source.