numerical modeling and observation of the fine sediments in the rio de la plata estuary claudia g....

Numerical Modeling and Observation Numerical Modeling and Observation of the Fine Sediments inof the Fine Sediments in

the Rio de la Plata Estuarythe Rio de la Plata Estuary

Claudia G. SimionatoClaudia G. SimionatoCIMA/CONICET-UBACIMA/CONICET-UBA

22ndnd MEETING OF IFAECI (UMI 3351) MEETING OF IFAECI (UMI 3351)Buenos Aires, Argentina, April 25Buenos Aires, Argentina, April 25thth 2011 2011

Outline

• History of the cooperation France-Argentina-Uruguay

• Reasons to study and model sediments• Achievements of the FREPLATA/FFEM Project• Pending scientific questions• Actions to increase cooperation• Ongoing projects and submitted proposals• What possibilities we see in the frame of the UMI

This cooperation starts as an initiative of IFREMER which manifested interest in applying its large experience in

sedimentological observation and modeling to the Río de la Plata

Efforts to understand processes in the Río de la Plata had already started in the frame of the FREPLATA I Project, but

sedimentology was not included yet

The contact between IFREMER and the regional research centers with interest and potential started

A proposal oriented to begin studies on sedimentological processes was submitted to the French Fund for the Global Environment

(FFEM) and a budget of around €1,200,000 was approved

CARP CTMFM

Why the study of the fine sediments Why the study of the fine sediments dynamics is a key scientific issue?dynamics is a key scientific issue?

Social and environmental impacts Social and environmental impacts

1.1. ContaminationContamination

Sediments moved by the flow are the main source

of contaminants, particularly heavy metals.

In the MTZ sediments (and contaminants) are

accumulated at the bottom flocculation, reduction of the current

speed?

Sediments are then resuspended by tides, currents and waves and contaminants enter in the trophic chain, with impact on fishes and

people

2. 2. DredgingDredging::

The entrance channels to the harbors of Buenos Aires and Montevideo demand continuous

dredging

Optimization of the dredging operations is an

important issue, which demands the

understanding of the sedimentological dynamics

Ecological problems what to do with the highly

contaminated muds dredged on harbors?

3. 3. Degradation of coasts Degradation of coasts and wetlands:and wetlands:

Samborombóm Bay is one of the most important wetlands of the region

It houses a rich ecosystem in which a large number of species of crabs,

fishes, turtles and migratory birds live.It is also the nursing area for a number

of species commercially fished.

Ongoing projects show that the bay is being eroded at very high rates, apparently by changes in the wind and

waves climate

The fine sediment dynamics is directly related with the erosion of these shallow

areas

Also, the shallow areas of the internal part of the system, where Buenos Aires is located, are object of large erosion

and environmental pressure because of anthropogenic actions.

The Paraná River Delta progresses over the Río de

la Plata. At the present growing rates it will be very close to Buenos Aires at the

end of this century.

This morphological evolution will cause impacts on the uses of the Río de la

Plata: drinking water, sailing, amusement,

dredging, etc.

It will affect, particularly the Mitre Channel (access to Buenos Aires Port).

The consequences of the changes can be mitigated only with planning, what needs as primary information

the understanding and modeling of the sedimentological processes.

4.4. Primary productionPrimary production::

Turbidity is the main limitation to the

phytoplankton grow. Therefore the

modeling of the population dynamics

rely on a proper modeling of the

sedimentological variables.

5. Fisheries5. Fisheries::

Environmental conditions have major influence on the distribution and structure of the species in the Río de la Plata.

A connection (it is not clear yet whether this is causal or casual) is observed between the spawning regions and the turbidity front.

Understanding the relationship between the environment and the fisheries is crucial for suggesting protection and conservation plans in an

ecosystemic management.

6. Bentonic organisms6. Bentonic organisms::

´The bentonic organisms are very dependent upon the bentonic

environment.Therefore, the distribution of

sediments determines in a large extent the diversity in a region.

The morphodynamical evolution by natural causes or anthropogenic

action can, therefore, have a large impact on the biodiversity of the

estuary

Understanding and modeling Understanding and modeling sedimentological processes is not easy…sedimentological processes is not easy…

The aim of the FREPLATA/FFEM project The aim of the FREPLATA/FFEM project was to set up the capabilities for state of was to set up the capabilities for state of the arts sediments modeling at the scale the arts sediments modeling at the scale

of the basinof the basin

Sedimentological processes are many and very complex: transportation, decantation, flocculation,

saltation, resuspension, consolidation…

Its modeling demands understanding and good modeling capabilities of the hydrodynamics

(tides, waves, currents, density field)

In contrast with the hydrodynamical processes, which obey to universal physical laws,

sedimentology is highly dependent on the site need of a large number of observations

230 km

50 km

320 km

Very large and shallow

Large runoff

Enormous solid discharge

In contrast with most of estuaries, highly sensitive to wind variability

The Río de la Plata presents its The Río de la Plata presents its own challengesown challenges

Understanding sediments’ dynamics

Observation

Modeling

In the frame of the FREPLATA/FFEM project, the approach was integral

Working groups

Hydrosedimentological modeling: IMFIA, CIMA, INA, IFREMER

Waves modeling: SHN

Data acquisition: SHN, SOHMA, INIDEP (cooperation of IFREMER, CIMA and IMFIA)

Data analysis: INIDEP, SHN, CIMA, IMFIA, INA, IFREMER

What advances were done in the frame of the Project?

1. Formation of human resources

Fellowship for a PhD student at CIMA (Diego Moreira)

Receiving a postdoc from IFREMER (at CIMA) (Caroline Tessier)

Courses at Facultad de Ciencias Exactas y Naturales de la Universidad de Buenos Aires (FCEN-UBA) training to students and researchers on sediments dynamics, observation, modeling and metrology (Florence Cayocca, Francis Gohin, Pierre Le Hir, Valerie Garnier, Michel Repecaud)

2. Collection of all the historical data and construction of a data repository

• Tides

• Current

• Waves

• Bottom and suspended sediments

• Bathymetry

• Others…

3. Acquisition of a unique data base of hydrosedimentological variables

• Fixed stations time series with high temporal resolution

• Oceanographic cruises synoptic view and high vertical resolution; installation and maintenance of the instruments

• Satellite observations longer term data; synoptic view

Torre Oyarvide

Pilote Norden

Pressure (waves)Temperature, salinityTurbidity

SMATCH TT

Fixed stations:

The buoy measures:meteorological variablestemperature, salinity, turbidity, oxígen, chlorophyll-a,currents (ADCP)

Data are currently received at CIMA

Oceanographic buoy

7 oceanographic cruises with 26 stations each (CTD, chlorophyll, turbidity, water and

sediments samples) 1 included yo-yo stations

http://www.ifremer.fr/nausicaa2/rioplata

Remote sensing data calibration and analysisMODIS and SeaWifs in 1 km y 250m, calibrated to SM and chlorophyll-a with IFREMER’s algorithms

Data were analyzed to observe the main patterns of variability in the estuary

4. Laboratory experiments

Understanding the consolidation processes

5. Implementation of the IFREMER’s hydrosedimentological MARS model for the Río de la Plata

Hierarchy of one-way nested models

The advances in numerical modeling have been:

•Installation of the model at CIMA, INA and IMFIA

•Validation of the hydrodynamics (tides and wind effect)

•Precalibration of the sedimentology and first sensitivity studies

•First process oriented simulations

We can provide a copy of the final report to those who might be interested

•Developing of a network of researchers and institutions good dynamics among participants and excellent possibilities for cooperative and synergic multidisciplinary research

•Acquisition of a unique data base of hydrosedimentological variables

•Formation of human resources

•Installation of capabilities in data acquisition, metrology and numerical modeling of hydrosedimentological processes in several institutions of Argentina and Uruguay

Main achievements of FREPLATA/FFEM project

What needs to be done in the future?

What needs to be done in the future?

Data acquisition and analysis

•Maintain the monitoring system operational long term records!•Improve observations in areas where there are still few data (for instance Samborombón Bay)•Develop specific calibration algorithms for the satellite images for the Río de la Plata and facilities for local processing•Exhaustive analysis of the data base collected during the project

What needs to be done in the future?

Modeling

•Complete the calibration of the model with the new data•Improve/adjust the parameterizations for the region•Add to the simulations more complex processes not included in the first studies•Begin the installation of other model’s modules•Improve wave modeling•Progress on operational modeling•Start building managements tools

What needs to be done in the future?

Processes

•Study the sensitivity of the sedimentological variables to natural variability/changes in the forcing•Understand the processes that maintain the MTZ•Understand and predict the morphological evolution•Understand the relationships between the environment and fisheries

Start biogeochemical numerical modeling studies and water quality studies

How are we progressing towards maintaining and increasing the cooperation?

Identification of new actors to produce synergy

INIDEP is developing a new remote sensing program and is interested on color data processing (resp. Carlos Lasta)

IAFE-CONICET is doing effort in the same direction (resp. Antonio Gagliardini)

Contacts and interactions already started

CERC (Centro de Estudios Regionales Costeros) and INIDEP are developing fisheries studies and collecting samples in the Río de la Plata (resp. Andrés Jaureguizar); they are incorporating PNA (Coast Guard) ships to make permanent monitoring and to assist in campaigns.

Contacts and interactions already started

Identification of new actors to produce synergy

Identification of new actors to produce synergy

FREPLATA II is a management project which aim is to start up the application of the Strategic Action Plan to reduce contamination and restore habitats proposed by FREPLATA I (Percy Nuggent)

The monitoring of the Río de la Plata is one of their needs they will probably be interested in contributing to maintain the instruments operating

Contacts and interactions already started (meeting on May 3rd)

Identification of new actors to produce synergy

SHN and DG-FCEN are conducting a project which aim is to observe and study the coastal erosion in the Buenos Aires littoral, including Samborombón Bay (resp. Walter Dragani and Jorge Codignotto)

Our researches are complementary.

CIMA and CERC are already cooperating in the project

Towards further cooperation with the Uruguayan institutions

CONICET (Dr. Jorge Tezón and collaborators) is doing actions in order to sign an agreement with ANII (Agencia Nacional de Investigación e Innovación) from Uruguay to facilitate the submission of joint proposals

Two research proposals have already been submitted

ANPCyT PICT (has been approved and will be financed) CIMA-SHN-INIDEP-IFREMERStudy of the sedimentological processes in the MTZ and their relation to fisheries

Cruises to maintain the instruments operationalOceanographic and biological observations in Samborombón Bay Waves observations in the upper estuary One fellowship for a PhD student at CIMA

ECOS (submitted on April 15th) CIMA-INIDEP-IFREMERFormation of human resources in satellite data processing (INIDEP)Installation of processing capabilities at INIDEPInstallation of a metrology lab at CIMA/DCAOFurther formation of human resources on numericalmodeling of sediments and biogeochemical processes

UMI IFAECI…

CIMA, IFREMER, INIDEP, CERC, SHN, INA, IAFE and IMFIA are willing to pursue and enhance their cooperation in this synergic multidisciplinary research.

The UMI provides an excellent framework for this collaboration.

The motivations and aims of the research conducted by this group of people contribute to the UMI agenda.

Through the UMI it might be possible to interact with more actors (particularly from social sciences) in order to make our research reach the society and/or be a part of a larger project in which our research might be applied to concrete problems.

Thank you!claudias@cima.fcen.uba.ar