Tidal Stream Atlas 219 covers Portsmouth Harbour and Approaches. Tidal stream atlases show, in diagrammatic form, the major tidal streams for selected waters of NW Europe. They show, at a glance, both direction and rate of tidal streams at hourly intervals by careful and accurate use of graded arrows. They also display mean neap and spring tidal rates in tenths of a knot. They include diagrams to assist you to calculate the tidal stream rate for your required day. Author: United Kingdom Hydrographic Office Publisher: United Kingdom Hydrographic Office Edition Date: 2nd Number of Pages: 25