Introduction

Digital marine weather records taken over the global ocean, based primarily on merchant ship observations, date back to 1854. These records and related statistics are available in the Comprehensive Ocean-Atmosphere Data Set (COADS). The cooperative effort that produced this widely used resource for climate research is a continuing project that started with COADS Release 1 (Slutz et al., 1985; Woodruff et al., 1987), which covers the period 1854-1979, and the recently completed COADS Release 1a (Woodruff et al., 1993), which extends the Release 1 products through 1992.

There are plans to update the record following World War II (COADS Release 1b) over the next year, with the scope of this update guided partially by the needs of the global atmosphere re-analysis project (Jenne, 1992), and later to update the entire period of record as the goal for Release 2. These efforts are intended to improve coverage during data sparse periods since 1854, extend the period of record back in time prior to 1854, and correct known problems where possible.

The work being accomplished today under the COADS project would not have been possible without the insight and devotion of many earlier mariners and researchers. Among the most important of these are Admiral Francis Beaufort who in 1805--as a Lieutenant in the British Navy--promoted the wind speed scale that now bears his name, and Matthew F. Maury, Superintendent of the U.S. Naval Depot of Charts and Instruments from 1842 to 1861, who helped organize international efforts to systematically collect marine data. Data collected by early mariners proved crucial to improving sailing times based on the knowledge of average weather and current conditions such as provided by Pilot Charts first developed by Maury.

Unfortunately, large quantities of the earliest records as well as numerous records from more recent periods such as the two World Wars, were never saved in digital form. Approximately one million U.S. Merchant Marine and Ocean Station Vessel (1940-1945) observations for the period 1938-1948 were punched on cards from WB (Weather Bureau) Form 1210A-Marine and archived as Deck 115. The cards were discarded in November 1960 because:

• punched cards were not then a recognized archive medium,
• an estimated 40% of the records contained errors (and adequate technology to perhaps correct these errors was not available), and
• the Ocean Station Vessel observations (a large portion of the deck) were maintained elsewhere.

All of the U.S.-recruited merchant marine logbook data prior to 1949, including Maury's own collection of logbooks, have not been digitized. Moreover, in many cases surviving original logbooks are in deteriorating condition. This paper discusses efforts by the COADS project, with the vigorous cooperation of a number of other countries in the international community, to improve data coverage and quality by locating and digitizing as many as possible of these records.