Patrick Luyten van Kbin-OD Natuur tenslotte stelde de laatste ontwikkelingen voor van de Coherens-software, en toonde ook enkele mariene en estuariene toepassingen.

1. COHERENS
A numerical tool for management of the
coastal marine environment
Patrick Luyten, Valérie Dulière, Geneviève Lacroix, …
RBINS‐OD Nature

2. Examples
Protection of beaches and coast lines
Fishery policies
Ports, shipping lanes, coastal industries, tourist areas
Pollutants from rivers and human-induced discharges
Operational forecasts
Climate change

3. Core
(hydrodynamics, numerical/parallel and
other common tools)
user-friendly interface for setup
standard data formats for easy
visualisation
inundation
waves biology
(microplankton, nutrients)
tracers sediment
structures module
(dams, groynes, discharges)
Lagrangian Eulerian dredging/relocationsea bed morphologywater column transport
available in progress planned
residence times
to be merged
model coupler
What does COHERENS contain?
Sea ice

4. Inundation schemes
Flow over an obstacle

5. Multiple weirs

6. Discharge module
Locations are either fixed or moving (e.g. ships)
Vertical position selected by the user:
o bottom
o surface
o fixed distance from the bottom
o fixed distance from the surface
Homogeneous or directional volume discharge
Discharged variable can be T, S, sediment or contaminant
concentration

7. Overview of the different modules
for sediments
Bed load module:
Algebraic equation
Sediment transport module
Morphological module
Suspended load:
Advection diffusion equation
Sediment transport module
Dredging dumping module

8. Morphological module
8
3 22
1
4
Update of bed elevation
Vertical sorting
Avalanching

9. COHERENS
• Wave parameters from SWAN
• Sea bed: enhancement of the bed
shear stress (important for
sediment erosion and bed load)
• Water column: Stokes drift and
wave radiation stress (2‐D and 3‐D)
Wave model (SWAN)
• Water depths and currents from
COHERENS for wave‐energy
equation
y g
Model coupler
• Exchange data between
COHERENS and SWAN using MCT
library
• Performs interpolations
• Generic to allow coupling with
other (e.g.meteorological) external
models or for 2‐way nesting
Wave-current interaction and
model coupling

10. User friendly set up
Objectives:
User-friendly setup
Standard data formats
Make COHERENS easier to use for less experienced users
Implementation:
Central Input File (CIF): comprehensive setup of model parameters using
(e.g.) short hand switches
Internationally recognized data formats (CF-1.6) for input/output
(netCDF) files

11. COHERENS
Climate studies
CORDEX,
CREST
Operational forecasts
OPTOS
Biology
MIRO&CO, CLIMARCO
Sediments
Indy67, Tiles
Capacity building
CEBioS
Tracers
oil spills, fish larvae,
Emosem, Jellyfor,
Newstep
Applications at RBINS
Data assimilation
JERICO, BCZ
Polar studies
(Recto)

15. Example of application :
Identification of potential polluters
Image from CleanSeaNet
Modelled
slick
Observed slick
Model results
Release
2012/10/10 6h08
Observed slick
2012/10/10 6h00

16. Forecast and backtrack of drifting objects
SAR (Search And Rescue)
Backtrack beached porpoises
Probable zones of death for beached porpoises
(spring 2006 and 2009)

17. - 6 main spawning grounds in the
North Sea,
Superindividuals (107 eggs)
3-month period
Spawning grounds: Eastern Channel, Belgian
Coast, Texel, German Bight, Norfolk, Thames
-4 -2 0 2 4 6 8
48.5
50.5
52.5
54.5
56.5
Longitude (°E)
Latitude(°N)
eggs/m²/d
FR
BE
NL
GE
UK
0
1.5
2.5
3.5
6
10
16
N
GB
Tx
BC
EC
Th
Redrawn from
ICES, 2005, Bolle et. In prep
Nurseries: France, Belgium, Netherlands,
Germany, Norfolk (UK), Thames (UK)
-4 -2 0 2 4 6 8
48.5
50.5
52.5
54.5
56.5
Longitude (°E)
Latitude(°N)
FR
BE
NL
GE
UK
No
GE
NL
BE
FR
Tha
- 6 nurseries: coastal areas (< 20m), high
proportion of sand and/or mud (from EMODNET-
GEOLOGY substrate map
Kaskela et al, 2010
-4 -2 0 2 4 6 8
48.5
50.5
52.5
54.5
56.5
Longitude (°E)
Latitude(°N)
FR
BE
NL
GE
UK
mud to sandy mud
sand to muddy sand
coarse-grained sediment
mixed sediment
bedrock
20 m
Intro Model Results CCL-Perspectives
IBM: spawning grounds & nurseries

18. -4 -2 0 2 4 6 8
48.5
50.5
52.5
54.5
56.5
Longitude (°E)
Latitude(°N)
FR
BE
NL
GE
UK
1995-2011
Final dispersal pattern
# larvae
Nurseries
No
Tha
Origin
-4 -2 0 2 4 6 8
48.5
50.5
52.5
54.5
56.5
Longitude (°E)
Latitude(°N)
eggs/m²/d
FR
BE
NL
GE
UK
0
1.5
2.5
3.5
6
10
16
N
GB
TxBC
EC
Th
Origin of the larvae
Spawning grounds
-4 -2 0 2 4 6 8
48.5
50.5
52.5
54.5
56.5
Longitude (°E)
Latitude(°N)
FR
BE
NL
GE
UK
No
GE
NL
BE
FR
Tha
Nurseries
Intro Model Results CCL-Perspectives

20. Forecast model simulation Source : wikipedia
Dispersion related
to release moment
(hourly release
during 24h)
Situation after 4 weeks

21. India: Mandovi/Zuari estuary

22. http://odnature.naturalsciences.be/coherens/
COHERENS international user group
(1727 registrations)