Analysing internal causality and sensitivityto derive coastal sea responses

to varying climate and anthropogenic forcing

Concept for an SFB at the University of Rostock

Presented by Hans BurchardLeibniz Institute for Baltic Sea Research Warnemünde

hans.burchard@io-warnemuende.de

Program of this presentation

• The Baltic Sea: a very special marine system• Changing Baltic Sea• Key questions of the SFB• SFB Structure• SFB Model Environment• SFB Graduate School

Baltic Sea drainage area

Mean freshwater run-off:

15000 m3/s

Dann kann aber doch fast gar kein Salz in der Ostsee sein ???

Baltic Sea monitoring

Salinity alongmonitoring section

Source: IOW

Major Baltic Inflow in January 2003

+

Darss Sill: 19 m

Oxygen alongmonitoring section

A century of salinity in the Central Baltic Sea

Graphics: Markus Meier (SMHI)

Phosphate feedback cycle in the Baltic Sea ecosystem

Have we understood triggers and limitations

of cyanobacteria blooms ?

Cyanobacteria observation I – Central Baltic Sea(cell counts)

Suikkanen et al. 2007

1975 1985 1995 2005 1975 1985 1995 2005

no clear long-term trend

no clear correlationbetween cyanobacteria andforcing factors

Cyaonobacteria observation II - whole Baltic Sea(from satellite)

data by Kahru et al. 2007

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RP*10

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1996 1998 2000 2002 2004 2006

cyano

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(graphics by Inga Hense, IOW)

large inter-annual cyanobacteria fluctuations at small variations of forcing

no clear long-term trend

We do not know the limiting and exitating factors for cyanobacteria blooms.

Many knowledge gaps are due to substantial undersamplingin time and space and in regulating parameters.

As long as we do not know how it works today, we have no predictivecapacity for future developments with respect to climate change andanthropogenic change.

19581960 1965 1970 1975 1980 1985 1990 1995 2000 20050

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Phosphate concentrations in winter surface layer in the Eastern Gotland Basin

The anthropogenic influence changes:

Reissmann et al., 2007

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Temperature deviation (K) from the 1900-1980 mean

Year A.D.

Dalton-min.

Maunder-min.

Spörer-min.

ModernWarm-P.

MedievalWarm-P.

Cold phaseincl. Little Ice Age

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Temperature deviation (K) from the 1900-1980 mean

Year A.D.

Dalton-min.

Maunder-min.

Spörer-min.

ModernWarm-P.

MedievalWarm-P.

Cold phaseincl. Little Ice Age

Laminated black mud(anoxic)

Laminated black mud(anoxic)

Light grey homogenous silt

(oxic)

Baltic climate of the past 1000 years

Figure SPM.5

Global climate change: emmission scenarios from IPCC 4th Assessment

http://www.ipcc.ch

Regional climate modeling at the Rossby Centre

Global Regional

Markus Meier (SMHI)

Markus Meier (SMHI)

The coupled system RCAO

Model domain, covering most of Europe and parts of the North Atlantic Ocean and Nordic Seas. Only the Baltic Sea is interactively coupled.

The coupling scheme of RCAO. Atmosphere and ocean/ice run in parallel.

OASIStmod

tcoup

ocean

atmos

rivers

landsurf

iceRCO

RCA

RCA: 44 km, 30 minRCO: 11 km, 10 minCoupling timestep: 3 h

Döscher et al. (2002)

Regionalization is done for ”time-slices” from GCMs

1800 1900 2000 2100

Present-day or a”control” climate

Climate scenario

CO2

Regional simulations

Results archived from a GCM-run

Time

(1961-1990) (2071-2100)

Markus Meier (SMHI)

Markus Meier (SMHI)

Sea surface salinity

Present climateProjection with the largest change

RCAO-E/A2

5 psu

Markus Meier (SMHI)

Markus Meier (SMHI)

Present climateProjection with the largest change

RCAO-E/A2

5 psu

52

77

145

836

1500

Sea surface salinity

Markus Meier (SMHI)

Annual mean SST (in °C) in present climate 1961-1990 (upper left), annual mean bias of simulated present climate compared to climatological data (upper right), and annual mean SST changes for the ensemble average (ECHAM4 and HadAM3H) of the B2 (lower left) and A2 (lower right) emission scenarios. The figure is taken from Meier (2006, Figs.13 and 14) with kind permission of Springer Science and Business Media.

Sea surface temperature:+1.9 … +3.9°C

Markus Meier (SMHI)

Mean number of ice days averaged for RCAO-H and RCAO-E: control (left panel), B2 scenario (middle panel), and A2 scenario (right panel). Figure is adopted from Meier et al. (2004).

Sea ice changes

Key questions of SFB

How can the abstract Baltic Sea response function and its interplay of linear and nonlinear processes be described in terms of logical, mathematical and numerical model components ?

How does the character of Baltic Sea inflow events react to climate change and which impact do these modified inflow dynamics have on the biogeochemical cascades which they trigger ?

How will the intensity and extent of cyanobacteria blooms react to climate and anthropogenic changes, and how will they interact with ecosystem dynamics of the Baltic Sea ?

How will spatio-temporal changes in near-bottom temperature, salinity and oxygen distributions affect the biodiversity and extent of benthic fauna, and which consequences does this have for the benthic-pelagic coupling in the Baltic Sea ?

Key questions of SFB

What is the role of redoxcline processes for overall biogeochemical cycles in the Baltic Sea and how are the communities and processes impacted by external forces (e.g., inflow events, turbulent mixing)?

Final overarching question:

To what extend does changing climate and anthropogenic forcing trigger ecosystem shifts in the Baltic Sea ?

Participating institutes

Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department of Limnology of Stratified Lakes

Leibniz Institute for Baltic Sea ResearchWarnemünde at the University of Rostock

Institute of Biological SciencesUniversity of Rostock

Swedish Meteorological and Hydrological Institute, Nörrköping

Structure of the SFB

P1: Pelagic processes – influence of light and inorganic carbon on primary production

P2: Cyanobacteria blooms – dynamics and performance of diazotrophic cyanobacteria

P3: Photorespiration, respiration, photoadaptation, and DNA micro-array

P4:Diatom-dominated biofilmsT1: Biologically mediated particle and solute fluxes between sediment and the benthic boundary layer

T2: Organisms’ functional capacityT3: Quantification of in-situ fluxes at the sediment water interfaceT4: Impact of turbulent transport intermittency on the biogeochemistry of pelagic redoxclines

T5: Small-scale processes in the upper layers of the Baltic ProperM1: Particle-associated carbon turnover origin, decomposition and sedimentation

M2: Structure and function of microbial communities in redox gradientsM3: Biogeochemical element transformations and fluxesS1: Baltic Sea climate reconstructionS2: Analysis of the present Baltic Sea state S3: Climate change and anthropogenic impact scenario simulations for the Baltic Sea

Spatial relation of the subprojects

SFB Model Environment

Logical and mathematical

model

Implementation into SFB-BGC Module

and1D testing

Testing in 3D Ecosystem Model

Process studies P, T & M

System simulations S1, S2, S3

Analysis of process

reproduction

Process understanding

required by models

Interlinking between process studies and modelling system

SFB Integrated Graduate School:

•for all SFB Ph.D. students•interdisciplinary teaching for all together•modelling courses with 1D model system•teaching in statistical methods•exercises in field & lab methods•soft skills •…

After this SFB, we will know far more about the Baltic Sea system than at present.