1. Paul BrownTides – Chartwork 3 rd Class Chartwork 3 rd Class Tides (Adapted from RYA Shorebased slides)

2. Paul BrownTides – Chartwork 3 rd Class What Causes Tides? Gravitational effects of the moon (and sun) which exert a pull on the water on the Earth's surface. What terms have you heard relating to tides? High Slack Ebb Flood Neap Range Stand Low Spring

3. Paul BrownTides – Chartwork 3 rd Class TIDES Sun Earth Moon

4. Paul BrownTides – Chartwork 3 rd Class TIDES - SPRINGS Earth New Moon Sun

5. Paul BrownTides – Chartwork 3 rd Class TIDES - SPRINGS Earth Full Moon Sun

6. Paul BrownTides – Chartwork 3 rd Class TIDES - NEAPS Earth First Quarter Neaps Sun

7. Paul BrownTides – Chartwork 3 rd Class TIDES - NEAPS Sun Earth Last Quarter Neaps

8. Paul BrownTides – Chartwork 3 rd Class TIDE TABLE 18 TH 0456 5.8 m 1205 1.7 m 1727 5.9 m HW LW Range 4.1 metres GMT

9. Paul BrownTides – Chartwork 3 rd Class TIDE TABLE 18 TH 0556 5.8 m 1305 1.7 m 1827 5.9 m Add an hour for British Summer Time

10. Paul BrownTides – Chartwork 3 rd Class TIDAL HEIGHTS - DEFINITIONS Chart Datum Charted depth (sounding) MHWS MLWS MLWN MHWN Depth of water Charted height Drying height

11. Paul BrownTides – Chartwork 3 rd Class TIDAL DIAMONDS & DATUMS Tidal streams referred to HW at PLYMOUTH

12. Paul BrownTides – Chartwork 3 rd Class TIDAL DIAMONDS & DATUMS 3 hours before HW Stream setting towards 318(T) Springs 2.9 kn Neaps 1.5 kn

13. Paul BrownTides – Chartwork 3 rd Class TIDAL STREAM ATLAS Atlas gives Direction & Rate of tidal stream for each hour 4 hours after HW PORTSMOUTH

14. Paul BrownTides – Chartwork 3 rd Class TIDAL STREAM ATLAS Thick and long arrows show strong stream Short and thin arrows show weak stream 4 hours after HW PORTSMOUTH

15. Paul BrownTides – Chartwork 3 rd Class TIDAL STREAM ATLAS 03,05 Rate of stream 0.3 kn at Neaps 0.5 kn at Springs 12,23 Rate of stream 1.2 kn at Neaps 2.3 kn at Springs Stream Slack