www.pol.ac.uk

The Liverpool Bay Coastal Observatory

John Howarth, Roger Proctor, Phil Knight, Mike Smithson

Real-time measurementsReal-time modelling Web display

An integrated monitoring system and research tool

Coastal Observatory - objectives

Water quality eutrophication, harmful algal blooms, pollution

Impacts of climate changeHabitats / biodiversityNatural and anthropogenic changescf National & EU directives, UN resolutionsEcosystem based approach to marine management

Search & Rescue / AccidentsEngineering – coastal, offshore – design, operation

Climate & biogeochemical cyclingCoastal ocean dynamics and ecosystemTurbulent mixing and biophysical interactions

Education, outreach

Time series & real time

Proof of concept (2001 – 2007 / 2012)Pre-operational near real time

measurements test modelsEvolutionaryFramework

anyone can joinprocess studies

Basic data / model output freeData management by BODCAudience

researchers, managers, general public, education

Steering group

Guiding principles

Irish

Sea

Liverpool Bay

Dee Estuary

Mersey Estuary

Why the Irish Sea ?

Semi-enclosed

Simple bathymetry

Tides – wide variation

Low runoff most in east

Lateral salinity gradients

Stratified & well- mixed regions

Weak advection (ann. av. north 2cm/s)

Pulsed storm events

Integrated measurements Variety of space and time scales

Real time

Multi-disciplinary

Measurements and models

In situ time seriesSites A and B

Spatial survey

HF Radar

Ferry

Satellite

B

A

Monitoring at the right scale

1cm1mm 1dm 1m 10m 100m 1km 10km 100km 1000km

1sec

1 min

1 hour

1 day

1 week

1 month

1 year

10 year

MolecularProcesses

Movementby Individual

TurbulantPatch size

SurfaceWaves

Inertial/InternalWaves

Tides

PlanktonMigration

Phytoplanktonbloom/patch

Monsoon

GyreCirculation

Storms

EdgeWaves

Seasonal Fronts

After Dickey

Range of strategies

Waves

Dec 2002 – Aug 2006(ADCP)

WindsApril 2004 – Sept 2006

Wind spectrum

CorrelationScalar = 0.988Vector = 0.849

Tz Correlation 0.67 / 0.96Mean diff 0.97 / 0.69(ADCP periods longer than buoy’s)

River discharge (Dee + Mersey + Ribble)

Tides - M2

Site A – blue

Site B – red

+ ADCP* Radar

Other tidal constituents (site A)

O1

M4

M6

Correlation coefficient 0.63

cf bottom stress

Residual currents

Site B

5 April 2005 – 22 Sept 2006

Near surface 0.045 m s-1

Near bed 0.030 m s-1

Sandwaves

7 Aug 2002 – 21 Sept 2006Near surface 0.025 m s-1 Near bed 0.040 m s-1

Site A

Mean current compared with theory

HF radar coverage

Coverage over mooring sites

Comparisons with in situ waves and current measurements (A&B)

First principal component (41% variance)

157 4 km cells

Spectra of residual currents

HF radar

Clockwise

Anti-clockwise

First principal component

Temperature

Salinity

Depth-averagedSurface minus bed

Four years CTD data

(38 visits)

Mersey Bar

97 %

13 %

Surface - bed at site A – all CTDs (251)

25 hour stations profiles every 30 minutes

9/10 May 200611/12 May 2004

Surface to bed differences November 2002 – March 2006

Temperature

Salinity

19 April – 18 June 2004

Temperature

Salinity

Surface - SmartBuoyBed frame

Mersey Bar

Site B

November 2005

5m below surface – blue

Sea bed frame - red

Temperature

Salinity

Wind and waves

Amplitude

Direction

Salinity

Sites A and B

Liverpool Viking, Birkenhead - Belfast

InstrumentsCTD – SeaBird SeaCat SBETurbidity – Sea PointFluorimeter – Chelsea Minitracka IIIntake 3m below surfaceSample interval – 30 secondsData transmission – Orbcomm

Start date – December 2003

Ferry – buoy(Site A)

Temp: r=0.99, sd=0.65 °C, mean=0.11°C,n=2599

Salinity: r=-0.05, sd=1.42, n=1117

Temperature - Birkenhead to Belfast

GreenMax / Min

Blue Mean

Red Mean±sd

2004/5South of IOM

Data Assimilation (EnOI)Isabel Andreu-Burillo

22/10/04forecast

SAF-constrained

22/10/04forecast(SAF+FB)-

constrained

22/10/04forecast

free simulation

21/10/04(SAF+FB)

observations

Nutrients

0

10

20

30

40

50

60

70

7-11-02 27-2-03 19-6-03 9-10-03 29-1-04 20-5-04 9-9-04 30-12-04 21-4-05 11-8-05 1-12-05 23-3-06 13-7-06

TO

XN

(m m

ol l

-1)

0

5

10

15

20

25

Si

(mm

ol

l-1)

NAS TOXNWMS TOXNShip TOXN

WMS SiShip Si

Nitrate

Winter Cruise data

0.00

10.00

20.00

30.00

40.00

50.00

60.00

30.00 31.00 32.00 33.00 34.00

Salinity

Bo

ttle

Nit

rate

NO3 14

NO3 15

NO3 23

NO3 24

NO3 32

NO3 33

Mean winter currents

Planned Operational models for Coastal Observatory

To run on POL cluster

12km

FOAM 1/9 degree (T,S, ζ, Q)

AMM-12km

MRCS -7km

IRS -1.8km

LB-200m

Real-timeRiver inputs

Met forcing, mesoscale 12km resolution(5km soon?)

Daily nowcasts/forecastsphysics (T,S, ζ, U,V, waves),

spm, light, nutrients, biology

MRCS, began 2002, 5-day forecast near real-time

SST BT

CHL ZOO

POLCOMS – ERSEM: MERSEA

55 state variables

Model - buoy comparisons

Web site –

http://coastobs.pol.ac.uk

Registration

Over 500 registrations

General public (55%)

Researchers (20%)

Coastal Managers (10%)

Teachers (10%)

Other (5%)

Future

Trace metal, benthic nutrient flux;dissolved oxygen, turbulence, pH, pCO2, biofouling, CDOMinstrumented ferry nutrients, water sampler

Improve data quality – eg salinity

Full suite of real time coupled hydrodynamic, wave and ecological models, inc Liverpool Baysalinity, circulation, light penetration, data assimilation

Data interpretation; synthesis of models & measurements

National, European and International collaboration

2007-12 (more ferries, third in situ site, drifters, gliders)

Links to policy: research -> sustained

Conclusions

4 years measurements

Measurements test models

Assessment of eutrophication status of Liverpool Bay

Questions

Variability of horizontal and vertical gradients

Circulation

Residual energy at tidal frequencies

Ebb – flood inequality

Events

International workshops on coastal observatories

First on 17-19 October 2006 in Liverpool, UK

“Best practice in the synthesis of long-term observations and models”

Covering aspects of utilisation of time series, data assimilation, optimisation (design) of observing systems, model configuration

For programme see. http://www.pol.ac.uk/home/coastal_obs_workshophttp://cobs.pol.ac.uk/home/news/events.php

Why the Irish Sea ?

Nutrient loading from Atlantic, atmosphere & rivers – elevated levels, EIS eutrophic?, HABs

Estuaries with different human impact (Dee-agricultural, Mersey-industrial)

Large human impact

Focus of Government activity - Biodiversity action plans - EU Water Framework and other directives - Offshore Renewable Energy - Marine Bill (UK and EU)Historical industrial legacy

Glider – 22 days; 1,000 km; 4,235 profiles (26 October – 17 November 2005)