Pilot charts, also referred to as routing charts, have been the most important passage planning tool since the middle of the nineteenth century. The first systematic study of ships' sailing routes, and the weather conditions that affect them, was undertaken in the 19th century by Lieutenant Maury of the US Navy with the aid of shipmasters' logbooks. Much of the information contained in the pilot charts that are in use today is still based on those observations and, although they have been updated at regular intervals, the scarcity of reliable sources, inaccuracy of the observations, or the climate changes that have occurred over the years, have rendered some of the information shown on those charts to be now inaccurate. To present as true a picture as possible of the actual conditions which prevail in today's oceans, the charts in Cornell's Ocean Atlas are based on extensive data collected by meteorological satellites from 1987 to the present. This data was processed by Ivan Cornell, whose programming experience has made both noonsite.com and this atlas possible. Sailors who have consulted advance copies of the atlas are describing it as ground-breaking for its content, but also for its organization and layout, which reflect Jimmy Cornell's unmatched world voyaging experience. The scale and range of charts are carefully chosen so that sailors can see all the relevant information and plan their passages on a single chart.