Concepts and Science for Coastal Erosion Management Data, Information and Tools for Effective Coastal Erosion Management James Sutherland HR Wallingford

Concepts and Science for Coastal Erosion Management

Data, Information and Tools for Effective Coastal Erosion

Management

James Sutherland

HR Wallingford


Data, Information and Tools for Effective Coastal Erosion Management

• We live in a data-rich age– If you can afford it

• There are many ways of collecting lots of data– From megabytes to terabytes

• Increased volumes of data do not necessarily help coastal management– Drowning in numbers


Data, Information and Tools for Effective Coastal Erosion Management

Purpose of this presentation:

• Review beach monitoring methods

• Review numerical modelling tools– Not necessarily useful for management

• Review data handling/display tools

• Explain role of coastal state indicators

• Provide monitoring guidance


Monitoring methods

• Point measurements– Tell-tail scour monitor

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Monitoring methods

• Cross-shore profiles– Theodolite,Total station, – DGPS, – CRAB, WESP,– laser scanner,– Argus or other camera system,– X-band radar.


Monitoring methods

• Map tidelines,• Ortho-rectified aerial

or satellite photos,• Topographic lidar • Bathymetric lidar• Synthetic aperture

radar – (side-looking airborne

radar)


Data management and display

• Modern systems capable of handling huge volumes of data through the data life-cycle

• Increasing importance of meta-data and international standards

• Measure once, use often

• Central data stores

• Use of GIS


Numerical Models for Erosion Management


Tools for Erosion Management

• Historical trend analysis– Often least-squares linear trend;– More sophisticated methods require more

data of better quality– Prediction relies on continuation of

historic trend



• One-line models– Simple but robust– Used to model decades of shoreline

positions

• Coastal profile models– Cross-shore erosion under storms– Poor at modelling beach recovery after

storms– Used to model days to weeks



• Coastal area models– Flows + waves + sediment transport +

morphology– Model areas are 102 to 104 km2

– Model simulates days to weeks– Extension to longer timescales through

simplification



• System models of morphology– SCAPE and ASMITA– Model simplified interactions between

elements;– Simulations of 10 to 103 years– Limited spatial resolution

• Systems models of flooding– RASP and PAMS in UK, VNK in NL


COAST3D question

• How can we use models and data to assist coastal management?

• Most detailed process models do not answer questions at the time and space scales that are of interest to coastal managers

• One approach is to use Coastal State Indicators


Coastal State Indicators

• “Coastal State Indicators for Coastal Erosion”– Tuesday, Session 18 ‘Coastal Erosion

Indicators’, 16:30 – 16:45, Europa Auditorium



• Coastal State Indicators are a “reduced set of parameters that can simply, adequately and quantitatively describe the dynamic-state and evolutionary trends of a coastal system.” – Jiménez and van Koningsveld, 2002

• Indicators used in implementing a policy


Frame of Reference


Frame of Reference



• Derived from analysis of system– Understanding state of system – Given a policy to implement– Chosen a means to implement the policy– Require thresholds– Adaptive management





• Dune strength, Barrier width, Backshore width, dune zone width, dune zone height

• Total barrier volume

• Momentary coastline, Beach width, Barrier crest position, Shoreline position,

• Coastal foundation, Shoreface volume, coastal slope



• Are being regularly used at three pilot sites;

• Are appropriate for the users;

• Not just data– Require a policy– Require a threshold


Monitoring guidance

• Monitor for a purpose:– Understand system– Derive coastal state indicators– Measure coastal state indicators

• Different stages may require different data

• Establish ground controls and datum

• Set standards

Documents

Concepts and Science for Coastal Erosion Management Data, Information and Tools for Effective Coastal Erosion Management James Sutherland HR Wallingford