Physical oceanography, tides and coastal flooding – the science behind it all. Dr Kevin Horsburgh Head of the National Tidal and Sea Level Facility Physics Teachers Conference 26 June 2008. Proudman Oceanographic Laboratory.
Dr Kevin Horsburgh
Head of the National Tidal and Sea Level Facility
Physics Teachers Conference
26 June 2008
Sea Palling, Norfolk (1 Feb 1953)
Oosterscheldekering (part of Delta works)
Thames Barrier (1987- )
Components of the UK coastal flood warning system surges and waves due to increased storminess, could impact on economic and social systems, as well as fragile ecosystems
Levee overtopping – Bay St Louis
Notable storm surges impacting the coast of Bangladesh since 1974
Cyclone 02B April 1991
F = ma
Synoptic situation on Friday 9 November 2007 surges and waves due to increased storminess, could impact on economic and social systems, as well as fragile ecosystems
18Z run on 8/11/08
Add in ice melt uncertainty
Downscale to get uncertainty in
Regional scale atmospheric
?Ensemble projections of change in extreme sea levels
Uncertainty in large scale atmospheric forcing
Run surge model simulations to estimate uncertainty range in local extreme water levels
Is the rate of rise increasing ?
Not clear. On basis of 20th century tide gauge data alone.
Yes. On basis of altimeter data from the 1990s.
But there is large decadal variability in all geophysical signals
P = h time-trend (from 5 largest per year)ρg
Tools for Measuring Sea Level Changes
Tide Gauges Satellite Altimetry Sea Floor Systems
Geodetic Tools for Measuring Land Level Changes time-trend (from 5 largest per year)
GPS Absolute Gravity
L Profiler (A.D.C.P.)Measurement of suspended particulates
Photo-diode Profiler (A.D.C.P.)