The first edition, published in 2012, was based on satellite observations undertaken in the previous 20 years (1991-2011). The second edition is fully revised and updated by incorporating data gathered during the last five years (2011-2016).  So the data now spans 25 years and also reflects any changes that have occurred during this latest period.Besides that, the new edition will also be reformatted to incorporate a new feature: monthly windgrams for the most sailed ocean routes. Windgrams are a summary of wind direction amd strength derived from the individual windroses along a specific ocean route.