2. 8-week running mean wave height Wave height at Sevenstones Lightship Year Date (day-month) Wave height (m) Average wave height (m) WAVES DURING 2013-2014 WINTER Hercules (W) Bridget (NW) Petra (SW) Ruth (W)

3. SW BEACH MONITORING SITES

4. STORM RESPONSE: SW ENGLAND Monitored beaches geographically arranged from Somerset to Dorset Change in sediment volume profile line (m 3 /m) BRISTOL CHL NORTH COAST SOUTH COAST

5. STORM RESPONSE: SW ENGLAND Monitored beaches geographically arranged from Somerset to Dorset Change in sediment volume profile line (m 3 /m) ROTATION

6. STORM RESPONSE: SW ENGLAND Monitored beaches geographically arranged from Somerset to Dorset Change in sediment volume profile line (m 3 /m) OFFSHOR E

7. BEACH RECOVERY: SW ENGLAND (post-storm – summer) Monitored beaches geographically arranged from Somerset to Dorset Change in sediment volume profile line (m 3 /m)

8. HOW CAN A BEACH LOOSE SAND/GRAVEL? Offshore – undertow, offshore bar migration, mega-rips Alongshore – Littoral drift, embayment rotation, headland by-passing

9. Car park ALONGSHORE SOUTH COAST: Carlyon Bay OFFSHORE NORTH COAST: Perranporth STORM RESPONSE SW ENGLAND

10. OFFSHORE: NORTH COAST Perranporth intertidal beach (long-term) Car park EROSION RECOVERY

11. Car park OFFSHORE: NORTH COAST Perranporth inter/sub tidal response Intertidal erosion Offshore accretion Rip channel Bar is 450m offshore of spring low tide

12. Car park OFFSHORE: NORTH COAST Perranporth inter/sub tidal response Intertidal erosion Offshore accretion Rip channel Bar is 450m offshore of spring low tide

13. Car park OFFSHORE: NORTH COAST Perranporth inter/sub tidal recovery

14. Change in sediment volume (m 3 /m) Distance from Torcross (km) Torcross Strete gate Car park ALONGSHORE: SOUTH COAST Slapton Sands response (post-storm)

15. Change in sediment volume (m 3 /m) Distance from Torcross (km) Torcross Strete gate Car park ALONGSHORE: SOUTH COAST Slapton Sands recovery (August)

16. before storms after storms P0 P11 P19 Response to Petra at Slapton Sands

17. Before During After

18. Response to Petra at Slapton Sands Before During After October

19. Response to Petra at Slapton Sands BeforeAfter

20. Breaking waves during Petra on Slapton Sands 3 m waves breaking at a 30-40 o angle with the shoreline generate longshore sediment transport > 10,000 m 3 per day

21. Sediment volume (m 3 /m) Wave height (m) Torcross (south end) Strete gate (north end) EasterlySoutherly ALONGSHORE: SOUTH COAST Slapton Sands (long-term)

22. CONCLUSIONS The 2013/2014 winter has been the most energetic winter for at least the last 60 years There are various mechanisms for removal of sand and gravel from beaches during storms, including: offshore, alongshore (rotation/headland by-passing) Coastal impacts are highly site- and storm-specific Limited recovery has occurred during the 2014 spring/summer due to: Wave climate Scale of storm impacts (extent of offshore/alongshore transport) Long-term morphological change (decadal) at Perranporth and Slapton indicate multi-annual cycles and trends associated with climate variations

23. NORTH COAST RESPONSE/RECOVERY Car park

24. NORTH COAST RESPONSE/RECOVERY Car park

25. FOUR EXCEPTIONAL STORMS Offshore wave heights 8–10+ m Coastal wave heights 5–7+ m, periods 15–23+ s (waves the height of a two storey house arriving at 200/hr)

26. Monitored beaches geographically arranged from Somerset to Dorset Change in beach (m 3 /m) Chesil Sennen St Ives Perranporth Westward Ho! STORM RESPONSE/RECOVERY: SW ENGLAND Monitored beaches geographically arranged from Somerset to Dorset Change in beach (m 3 /m) Sennen St Ives Perranporth Westward Ho!