HELCOM Baltic Sea Action Plan in a warmer world

H.E. Markus Meier1,2

1Research Department, Swedish Meteorological and Hydrological

Institute

2Department of Meteorology, Stockholm University

E-mail: markus.meier@smhi.se

Content

Results of the ECOSUPPORT project Discussion of limitations of the approach Recommendations for future research

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Baltic Sea - how to approach the future?

COD SPRAT

Combined effects of climate change and nutrient loads

Ensemble modelling to quantify uncertainty

Decision support to policy makers

Baltic Sea - how to approach the future?

COD

11 partner institutes from 7 Baltic Sea

countries 2009-2011

Advanced modeling tool for scenarios of the Baltic Sea

ECOsystem to SUPPORT decision making

www.baltex-research.eu/ecosupport

Baltic Sea: future projections

COD SPRAT

• 4 climate projections 1961-2099

• 2 different global climate models

• A1B and A2 scenarios

• 2 realizations

• 1(2) regional climate model (RCAO, CLM)

• 1(2) hydrological models

• 3 Baltic Sea models (BALTSEM, ERGOM, RCO-SCOBI)

• 3(4) nutrient load scenarios: BSAP, (CLEG), REF, BAU

• Total: 38(58) scenario simulations

Ensemble mean volume averaged temperature and salinity

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(Source: Meier et al., 2011a)

Ensemble average changes of the annual mean biologically available total nitrogen

and phosphorus loads

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(Source: Meier et al., 2011a)

Ensemble average vertical profiles and changes between 2069–2098 and 1978–2007 in oxygen

concentration at Gotland Deep

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observations BAU

REF

BSAP

(Source: Meier et al., 2011a)

Volume averaged anoxic areas

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REF

BSAP

BAU

observations (Source: Meier et al., 2011a)

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Ensemble mean changes between 2069–2098 and 1978–2007 of a–d annual mean phytoplankton concentration (in mg Chl m-3) and e–h Secchi depth (in m)

BSAP CLEG REF BAU

(Source: Meier et al., 2012c)

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BAU REF BSAP

Primary production

Phosphorus release from the sediments

Sediment phosphorus pool

Denitrification

Ratio between release and phosphorus sediment pool

Ratio between denitrification and nitrogen supply

Nitrogen release from the sediments

Nitrogen fixation

(Source: Meier et al., 2012c)

Conclusions • In future climate, increased loads and

temperature dependent rates of biogeochemical processes may result in an overall intensification of internal nutrient cycling, including substantial increases in both primary production of organic matter and oxygen consumption for its mineralization.

Conclusions • Without drastic nutrient load abatements

hypoxic and anoxic areas are projected to increase. The BSAP does not result in an oligotrophic Baltic Sea (“prior to 1960s” roughly).

• ECOSUPPORT was a big step beyond the state-of-the-art because we used

1. transient simulations 1960-2100 (1850-2100) 2. multi-model ensemble approach

AMBIO Special Issue,

September 2012

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Conclusions Uncertainties of the projections are dominated by 1. unknown nutrient loads (bioavailability,

nutrient retention in the coastal zone, scenarios),

2. biases of the GCMs/RCMs (hydrological cycle, estuarine circulation) and

3. biases of the biogeochemical models. For instance, we found largely differing sensitivities of the models to changing nutrient loads. In addition, the northern Baltic Sea biogeochemistry seems to be less well described.

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Monthly mean 2m air temperature at Gotland Deep for 1980-2006 (RCA with 50km)

(Source: Meier et al. 2011b)

Water temperature

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SST changes versus air temperature changes for winter and summer

(Source: Meier et al., 2004c)

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2013-02-07

Seasonal SST changes (°C) RCAO/HadCM3 A1B (upper) and RCAO/ECHAM5 A1B (lower) 2089-2060 minus 1970-1999

DJF MAM JJA SON

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2013-02-07

Seasonal SST changes (°C) RCAO/HadCM3 A1B (upper) and RCAO/ECHAM5 A1B (lower) 2089-2060 minus 1970-1999

DJF MAM JJA SON

Northern Baltic amplification confirmed by satellite data

Salinity

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Ensemble mean volume averaged temperature and salinity

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(Source: Meier et al., 2011a)

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Relative changes in precipitation (in percent) for the period 2090–2099, relative to 1980–1999. Values are

multi-model averages based on the SRES A1B scenario for December to February (left) and June to August

(right).

White areas are where less than 66% of the models agree in the sign of the change and stippled areas are where more than 90% of the models agree in the sign of the

change.

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Relative changes in precipitation (in percent) for the period 2090–2099, relative to 1980–1999. Values are

multi-model averages based on the SRES A1B scenario for December to February (left) and June to August

(right).

White areas are where less than 66% of the models agree in the sign of the change and stippled areas are where more than 90% of the models agree in the sign of the

change.

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Median profiles of salinity at monitoring station BY15 for present climate 1961-1990 (black solid line, shaded areas indicate the +/- 2 standard deviation band calculated from two-daily values for 1903-1998) and in projections for 2071-2100 (colored lines). In (a) only effects from wind changes are considered whereas in (b) projections based upon wind and freshwater inflow changes are shown. Numbers in the legend correspond to the different scenario runs. (Source: Meier et al. 2006)

Salinity at Gotland Deep

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Kattegat

Baltic proper

Bothnian Sea

Bothnian Bay

Gulf of Riga

Gulf of Finland

Total

Runoff

Source: Meier et al. (2012b)

27 Sensitivity of salinity to the freshwater supply

sensitivity experiments

scenarios

natural variability

present climate

(Source: Meier and Kauker, 2003b)

Recommendations for future research

1.New scenario simulations are needed based upon IPCC AR5 (sea ice, hydrological cycle, larger ensemble, saltwater inflows, sea level rise)

2.Climate - land use – socioeconomy interaction/feedback

3.More plausible nutrient load scenarios consistent with large-scale developments

4.Multi-stressor approach (warming, de-oxygenation, eutrophication, overfishing, invasive species, pollutants)

5.Cost-effective implementation strategies of the BSAP will be developed based upon the information from spatially and temporally highly resolved modelling.

BALTEX and BSAP 7th Study Conference on BALTEX Borgholm, Island of Öland, Sweden, 10 to 14 June 2013 Changes in Energy, Water and Matter Cycles - 20 Years of

BALTEX Research Building Regional Earth System Knowledge - A future

programme for the Baltic Sea region

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Vision: Open international and interdisciplinary collaboration network providing service to society in the respect that thematic assessments (like BACC) provide an overview over knowledge gaps which need to be filled (e.g. by funded projects).

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Thank you for your attention!

Cyanobacteria

bloom 2008