International Conference and Young Scientists School on Computational Information Technologies for

Environmental Sciences: “CITES-2005”Novosibirsk, Russia, March 13-23, 2005

Atmosphere-Sea Hydrodynamic-Ecosystem model study in the sea

Rein Tamsalu (University of Tartu)

Introduction

Today the environmental science are very much coupled with everyday life. Management policies need answer to concrete questions concerning the response of nature to both natural and manmade changes in enviromental forcing factors and loding.

Numerical Hydro-Ecological modelling is an important tool for a better undrstanding of relations between the processes, and for forecasting these responses.

Atm.-Sea-Hydro-ecological forecasting modelling

The goal of our activities is to answer to concrete questions concerning the

response of nature to both natural and man-made changes

in marine environment.

*

Concrete Questions

The influence of the Port of Tallinn reconstruction

to the Muuga Bay marine environment

The influence of the Port of Tallinn reconstruction to the Muuga Bay marine environment

Baltic Sea =3’ =6’ Gulf of Finland =1’ =2’

Talsingi =0.25’ =0.5’ Gulf of Muuga =0.05’ =0.1’

Atm.-Hydro-Ecological forecasting modelling

In the Atmosphere-Sea-Hydro-Ecological

modelling system are coupled several

sub-models:

*

Atm.-Sea-Hydro-Ecological Models System

FRESCO (Finnish Russian EStonian COoperation)

Weather Forecasting Model HIRLAM (FMI)Weather Forecasting Model HIRLAM (FMI)

Atm. Boundary Layer ModelS. Zilitinkevich (HU)

Atm. Boundary Layer ModelS. Zilitinkevich (HU)

Atm. Poll. Trans. ModelM. Hongisto (FMI)

Atm. Poll. Trans. ModelM. Hongisto (FMI)

Wind Wave ModelV.Zakharov (IO)

M. Zaslavskii (IO)J. Kabachenko (SOI)

Wind Wave ModelV.Zakharov (IO)

M. Zaslavskii (IO)J. Kabachenko (SOI)

Circulation ModelV. Zalesny (INM)R. Tamsalu(UT)

Circulation ModelV. Zalesny (INM)R. Tamsalu(UT)

Oil Spill ModelS. Ovsienko (SOI)Oil Spill Model

S. Ovsienko (SOI)

EMHI-Est. Meteor. And Hyd. Inst.FMI-Finnish Meteorol. Inst.HU -Helsinki UniversityINM-Inst. of Num. Math. (Moscow)OI -Oceanological Inst. (Moscow)SOI-State Ocean. Inst.(Moscow)TU -University of Tartu

Ecological ModelR. Tamsalu (UT)

H. Kuosa (HU)

Ecological ModelR. Tamsalu (UT)

H. Kuosa (HU)

Meso-scale Atm. ModelR. Rõõm, A. Männik (UT)

Ivar Ansper (EMHI)

Meso-scale Atm. ModelR. Rõõm, A. Männik (UT)

Ivar Ansper (EMHI)

k-( )Model

R. Tamsalu(UT)

k-( )Model

R. Tamsalu(UT)

Meso-Scale Atmosph. Model

TU-EMHI modelETA model is based on the reference HIRLAM model, ETB is the non-hydrostatic version.

A pre-operational version of nonhydrostatic HIRLAM is used at the Estonian Meteorological Hydrological Institute (EMHI) to test the non-hydrostatic kernel of the model. Two modelling domains, as illustrated in Figure 1, are in use. Grid size of the larger domain ETA is 11km and the smaller domain ETB 3km. As the limited area models require boundary fields from larger models, the ETA model is nested to the FMI operational HIRLAM and ETB to the ETA.

Meso- Scale Atmospheric Model

ETA-6 * 6 nm

ETB-1.5*1.5 nm

Marine Circulation Models

There are many different models

barotropicbaroclinichydrostaticnonhydrostatic.......................

Measured Temperaure Vertical Stucture in the Muuga Bay

Velocity Measurements In Muuga Bay

Recording Doppler Current Profiler RDCP 600 ( Aandera Instruments AS, Bergen, Norway.)

Marine Circulation Model

It is clear that we need

Baroclinic Nonhydrostatic Circulation Model

Marine Circulation Model The governing equations of the circulation model are:

Momentum equation for velocity vector U (u,v,w)Continuity equation for incompressible fluid

Transport-diffusion equations for: Salinity S

Temperature T

State equation for buoyancy b=f(T,S)Two-equation turbulent model for Kinetic energy k and generic length scale quantity or

sea level fluctuation , hydrostatic pressure p* and nonhydrostatic pressure p’

Pressure components

are calculated

Wind wave calculation

Surface wind waves are an integrated effect, in space and time, of driving wind fields.The wind wave model computes the two-dimensional wave action spectra through integration of the transport equation, where the right hand side consists of several terms describing different evolution mechanisms, such as

•energy input from wind ;•the non-linear transfer of energy through the spectrum ;•different kinds of dissipation mechanisms.

Interactive atmospheric input term is used in the Miles’ form.In this model the so-called narrow-directional approximation is used. This approximation is based on well-known fact that wind waves have a narrow angular spreading function of spectra. The latter circumstance plays a key role in parameterization of nonlinear term.

*

Size-Dependent Pankton Community ModelSize- dependent plankton community food web is formed by

autotrophs (Ai ) i=1,2,…,NP

heterotrophs (Hi ) i=1,2,…,NP

bacterioplankton (B )

This plankton community forms the NP triplet stucture.

Size- dependent plankton community food web is formed by autotrophs (Ai ) i=1,2,…,NP

heterotrophs (Hi ) i=1,2,…,NP

bacterioplankton (B )

This plankton community forms the NP triplet stucture.

Zooflag.Zooflag.

Microzoopl.Microzoopl.

DIP

DIN

DIC

DIP+DOP

DIN+DON

DOC

Picophyto.Picophyto. Bacteriopl.Bacteriopl.

ESD (m)

0.2 - 2I

Phytoflag.Phytoflag.

Nanozoopl.Nanozoopl.

II 2 - 10

Nanophyto.Nanophyto.III 10 - 50

Netphyto.Netphyto.

Mesozoopl.Mesozoopl.

IV50 - 250

250 – 1250

Growth reactions

There are two energy flows to the plankton community

The first one is the uptake of dissolved inorganic nutrients by autotrophy

and it is directed from the autotrophy toward heterotrophy trough grazing .

The other is the uptake of dissolved organic and inorganic nutrients by

bacterioplankton and it is directed from bacterioplankton towards

heterotrophy trough predation.

|

Loss reactions

Energy is lost through

autotrophy exudation , mortality and respiration

heterotrophy excretion, mortality and respiration

bacterioplankton excretion and respiration

detritus decay

|

Different grid resolutions

Baltic Sea Gulf of Finland

Talsinki area

Muuga Bay

open boundary

I - 3.0 * 3.0 nmII - 1.0 * 1.0 nmIII- ¼ * ¼ nmIV- 1/20 * 1/20 nm

Horizontal velocity on the surface layer

Muuga Bay

Muuga Bay

HORIZONTAL VELOCITY IN THE BOTTOM LAYER

Muuga Bay

Muuga Bay

Velocity on the cross-section

Muuga Bay

Wind Waves In TALSINKI area during SW Storm

24.50 24.60 24.70 24.80 24.90 25.00 25.10 25.20 25.30

59.40

59.50

59.60

59.70

59.80

59.90

60.00

60.10

Ecological compounds calculation

Autotrophs in the beginning of May

Heterotrophs in the beginning of May

Suspended Material Calculation

Spawning place

Reconstruction area

Oil Spill calculation

    Stranding of oil and shoreline interaction

The following oil spill processes are modeled:

Transport and deformation of an oil slick due to time and spatially varying winds and currents

•Diffusion and dispersion of oil on the sea surface and in the water column

•Evaporation of a multi-component mixture of oil

Sinking of oil in water, and consequent sedimentation

Formation of oil-in-water emulsion

Weathering of oil, resulting in changes in density, viscosity, and water content, due to evaporation and emulsification processes

Oil spreading at the sea surface due to positive buoyancy

Oil Spill calculation

The probability of the oil accident consequence in the NW part of the island

Saaremaa in the summer time during three months.

The influence of the Wind Waves

to theBaroclinic Circulation

Surface Temperature after 30 days calculation

No Wind Waves

Wind Waves are included

Bottom Temperature after 30 days calculationNo Wind Waves Tmax=10Tmin=6.5

Wind Waves are included Tmax=10Tmin=6.5

Temperature profile after 30 days calculation

No Wind Waves Tmax=10 Tmin=6.5

Wind Waves are included Tmax=10 Tmin=6.5

Eddy Viscosity profile after 30 days calculationNo Wind Waves

Wind Waves are included Kmax=100cm2/s. Kmin=0.1 cm2/s.

Surface velocity after 30 days calculationNo Wind Waves

Wind Waves are included

Bottom Velocity after 30 days calculationNo Wind Waves

Wind Waves are included