MOF, Alm.del - 2016-17 - Endeligt svar på spørgsmål 809: Spm. om vurdering af miljøtilstanden i de områder af Kattegat, der er vurderet som egnet til havbrugsproduktion, til miljø- og fødevareministeren

Miljø- og Fødevareudvalget 2016-17
MOF Alm.del
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Summary report on the development of revised Maximum

Allowable Inputs (MAI) and updated Country Allocated

Reduction Targets (CART) of the Baltic Sea Action Plan

This document was prepared for the 2013 HELCOM Ministerial Meeting

to give information on the progress in implementing

the HELCOM Baltic Sea Action Plan

Baltic Marine Environment Protection Commission

MOF, Alm.del - 2016-17 - Endeligt svar på spørgsmål 809: Spm. om vurdering af miljøtilstanden i de områder af Kattegat, der er vurderet som egnet til havbrugsproduktion, til miljø- og fødevareministeren

Summary report on the development of revised Maximum

Allowable Inputs (MAI) and updated Country Allocated

Reduction Targets (CART) of the Baltic Sea Action Plan

0 Summary ........................................................................................................................... 2

2.1

2.2

4.1

4.2

4.3

4.4

4.5

6.1

6.2

Background ............................................................................................................... 4

Revision of nutrient reduction scheme ................................................................... 5

Revised eutrophication (status) targets ................................................................... 5

Allocation principles................................................................................................. 5

How are revised MAI calculated............................................................................... 7

How are updated CART determined ........................................................................ 8

Establishing a complete dataset on air- and waterborne inputs to the Baltic Sea .... 8

Transboundary inputs .............................................................................................. 9

Steps for calculating country allocated reduction targets (CART) ...........................10

Proposed CART .....................................................................................................12

Division of reduction requirements on an air- and a waterborne part ......................14

Progress ...................................................................................................................14

Perspectives ............................................................................................................15

Response in the Baltic Sea to the nutrient input reductions ....................................15

Validity of the results of the revised BSAP nutrient reduction scheme figures ........16

Why not consider economy before MAI and CART are settled ...............................17

Uncertainty of the MAI and CART figures ...............................................................17

Implications of climate change on MAI, CART and needed measures ....................17

References ...............................................................................................................18

Definitions/Glossary ................................................................................................19

Technical Annex ......................................................................................................20

Page 1 of 22

0 S

UMMARY

The aim of this summary report is to describe in a concise way how the revised HELCOM

Baltic Sea Action Plan (BSAP) Maximum Allowable Inputs (MAI) and updated Country

Allocated nutrient Reduction Targets (CART) have been developed. The main target

audience of this report is the decision-makers of the Baltic Sea coastal countries, as well as

any stakeholders interested in understanding the revision process of the nutrient reduction

scheme of the HELCOM Baltic Sea Action Plan.

The HELCOM Nutrient Reduction Scheme is a regional approach to sharing the burden of

nutrient reductions to achieve the goal of a Baltic Sea unaffected by eutrophication, as

agreed on by HELCOM.

The Scheme was first introduced and agreed on in 2007, in the HELCOM Baltic Sea Action

Plan. At that time, the countries agreed on provisional nutrient reduction targets and decided

that the figures would be revised using a harmonised approach and most updated data as

well as through enhanced modelling. The revision process started in 2008 and has been

completed in 2013.

There are two main components of the nutrient reduction scheme:

•

Maximum Allowable Inputs (MAI)

of nutrients, indicating the maximal level of inputs

of water- and airborne nitrogen and phosphorus to Baltic Sea sub-basins that can be

allowed to fulfill the targets for a non-eutrophied sea;

•

Country Allocated Reduction Targets (CART),

indicating how much the HELCOM

countries need to reduce nutrient inputs compared to a reference period (1997-2003).

A great deal of work has been carried out to improve the scientific basis of the scheme.

1. New eutrophication targets describing

good eutrophication status of the Baltic

Sea

2. Improved marine model (BALTSEM) of the

Baltic Nest Institute (BNI) Sweden

3. Calculation of revised Maximum Allowable

Inputs (MAI) with BALTSEM, using new

eutrophication targets for Baltic Sea sub-

basins

4. Agreement of allocation principles for

calculating new Country Allocated

Reduction Targets (CART)

5. Updated dataset on water- and airborne

nutrient inputs for 1994-2010

6. Calculation of new Country Allocated

Reduction Targets (CART)

7. Scientific documentation of the process

Non-

eutrophicated

water

Eutrophicated

water

Detailed information on the development and calculation of MAI and CART will be included in

the scientific report by the Baltic Nest Institute (BNI, Stockholm) “Revision of the Maximum

Allowable Loads and Country Allocation Scheme of the Baltic Sea Action Plan” (Gustafsson

& Mörth, in prep).

Page 2 of 22

the nutrient reduction targets, as well as the Ccountry-wise nutrient reduction targets

including updated information on the atmospheric nitrogen deposition by 2012.

2 R

EVISION OF NUTRIENT REDUCTION SCHEME

Since 2008, work has been on-going to improve the nutrient reduction scheme, including:

•

The scientific basis for review of the ecological targets for eutrophication of the

HELCOM BSAP within the

TARGREV project,

•

The

Baltic Nest Institute-Sweden

(BNI) has further developed its marine models to a

new BALTSEM model for calculating the MAI,

•

The

HELCOM PLC-5.5 project

has compiled an updated and more complete data set

on waterborne and airborne pollution inputs to the Baltic Sea. The data set covers the

period of 1994-2010 and input data has also been normalized to smooth out the

influence of annual variations in weather conditions,

•

BNI has developed a new software tool for calculating CART,

•

Allocation principles have been revised.

Furthermore, the HELCOM Expert Group on follow-up of national progress towards reaching

BSAP nutrient reduction targets (HELCOM

LOAD)

has been developing tools for following up

on fulfilment by the countries regarding the nutrient input reduction requirements (Larsen,

S.E. and Svendsen, L.M., in press).

2.1 Revised eutrophication (status) targets

The revision of the scientific basis underlying the ecological targets for eutrophication was

carried out by the HELCOM TARGREV project (HELCOM, 2013).

In the 2007 BSAP only one indicator for good environmental status with regard to

eutrophication - clear water/transparency (expressed as annual average Secchi depth) - was

used to calculate MAI. To increase the reliability of the eutrophication status assessment,

four more eutrophication indicators have been developed.

Indicators used to describe the Baltic Sea in a good environmental status

with regard to eutrophication.

•

BSAP 2007

Secchi depth (annual)

•

2013

Secchi depth (summer)

winter nutrient concentrations of DIP

winter nutrient concentrations of DIN

Chl α (summer)

oxygen debt/concentration

Eutrophication status targets are available for all 18 HELCOM open sea areas (Table 9.2 in

the Annex, HELCOM HOLAS sub-division). However, they have been aggregated into the

seven-basins that MAI are calculated on and correspond to the ones used in BSAP 2007

(Table 9.3 in the Annex).

2.2 Allocation principles

One step in developing the revised MAI and CART is the agreement on allocation principles

for calculating updated Country Allocated Reduction Targets. The overall principle is the use

of the polluter pays principle according to Article 3 in the Helsinki Convention (HELCOM,

1992). It has been supplemented with further principles as listed in Table 2.

Page 5 of 22

Table 2. Comparison of allocation principles used for BSAP 2007 and the new nutrient reduction scheme.

Allocation Principle

Polluter pays

Maximum Allowable Inputs

Reference inputs

Reference period

Flow normalization

Compensation for improved sewage treatment

Retention deducted on transboundary inputs

Common pool

Yes

BSAP 2007

Yes

Waterborne inputs

1997-2003

Yes

BSAP Review 2013

Water- and airborne inputs

1997-2003

Yes

No, but instead non-

Contracting Parties’

waterborne inputs are

allocated to the emitting

country

Yes

Gothenburg Protocol expected reductions by

2020 from non-Contracting Parties

Expected reductions from shipping

In BSAP 2007 all atmospheric deposition of phosphorus and nitrogen (amounting to 6,300

tonnes phosphorus and 230,000 tonnes nitrogen respectively) was treated as background

inputs to the Baltic Sea (it was taken into account when deriving MAI but the reduction

targets were only calculated from, and allocated on, the waterborne inputs).

Atmospheric nitrogen deposition originating from HELCOM countries’ emissions are

now included in the updated reduction targets.

As a consequence HELCOM countries

have to meet the reduction target also for sub-basins they are not bordering to. Reductions in

both airborne and waterborne nitrogen inputs can be accounted for in fulfilling the reduction

targets.

All

atmospheric phosphorus input is also this time treated as background input

as the

sources to these inputs are not known. A survey of available monitoring of phosphorus

deposition has led to a revised deposition estimate from the 6,300 tonnes used in BSAP

2007 to 2,100 tonnes phosphorus for the whole Baltic Sea, using a fixed deposition rate of 5

kg P km

-2

in the 2013 revision.

Keeping the 1997-2003 reference period makes it easier and statistically safer to

evaluate trends and effects

of taken measures since

long time series are available.

The reference (1997-2003) waterborne inputs used in BSAP 2007 and the new waterborne

reference inputs are shown in Table 9.4 (cf. Annex). The new waterborne reference inputs

have been updated with updated and corrected pollution input data and flow normalization.

In BSAP 2007, an

ex ante

reduction of discharges from municipal wastewater treatment in

countries not fulfilling the HELCOM Recommendation and EU UWWT Directive was applied

in the CART calculation, while some countries (Sweden, Denmark and Germany) received

an extra bonus as compensation for higher treatment levels than required.

In the revised

scheme the

ex ante

principle has not been applied.

BNI studies during 2010-2011 show

that it is not possible to accurately estimate the sewage treatment potential. Further,

according to the polluter pays principle reduction requirements to a sub-basin are divided

according to real input of each HELCOM country. Therefore, if a HELCOM country has

reduced their wastewater emissions they also get a lower reduction requirement, and hence

ex ante

accounting would lead to a kind of double compensation.

For two border rivers between the Contracting Parties (Neva and Torne rivers), the riverine

inputs are divided according to the agreed proportion of input from the involved countries.

Page 6 of 22

In BSAP 2007, transboundary waterborne inputs reaching the Baltic Sea from non-HELCOM

countries was estimated without taking into account the retention on the transboundary

inputs from the border down to the coast.

For calculation of the new CART, retention is

deducted from the transboundary waterborne inputs entering HELCOM countries.

Retention plays an important role as on average 25-50% of nitrogen and 30-60% of

phosphorus entering as transboundary inputs in the coastal countries are retained in the

catchment before rivers enter the Baltic Sea. Retention in coastal areas, after waterborne

inputs have entered the Baltic Sea, is not taken separately into account and is indirectly

included in the BALTSEM model when it is calibrated with water- and airborne inputs.

In BSAP 2007 a common pool of was allocated for transboundary waterborne inputs from

upstream countries such as Belarus. The common pool of 3,779 tonnes of nitrogen and

1,662 tonnes of phosphorus was based on a very rough estimate of potential input

reductions resulting from improved waste water treatment in Belarus and inputs via rivers to

the Baltic Sea.

The revised CART take into account expected reductions of transboundary inputs from non-

HELCOM countries. For the waterborne transboundary inputs, the expected reductions are

calculated by allocating according to the same principles as for HELCOM countries, which

lowers reduction requirements for the countries with waterborne inputs to the Baltic Proper

and the Gulf of Riga. Also the expected

reduction of atmospheric nitrogen

deposition due to the implementation of

the Gothenburg Protocol in non-

HELCOM countries is taken into

account. This lowers nitrogen reduction

requirement for all HELCOM countries

to the Baltic Sea sub-basins. Further,

80% reduction of nitrogen deposition

originating

from

shipping

(implementation of the Baltic NECA) is

assumed.

OW ARE THE REVISED

MAI

CALCULATED

MAI is calculated using the coupled

physical-biogeochemical model

BALTSEM. The model simulates

circulation and development of

stratification driven by meteorology, river

flow and boundary conditions to the

North Sea, as well as simulating cycles

of inorganic and organic nutrients and

dominating plankton groups.

Figure 3. The basin division of the Baltic Sea and the parts of the catchment contributing to the waterborne inputs to

each of the basins. Further the borders of Contracting Parties are inserted to illustrate that besides the 9 HELCOM

countries five countries: Belarus, Ukraine, Czech Republic, Slovakia and Norway contribute with waterborne inputs to

the Baltic Sea (transboundary waterborne inputs).

The model explicitly takes into account sediment biogeochemistry so that the complete

nutrient cycles of phosphorus, nitrogen and silica, including their internal loading, are

covered.

Obtaining MAI is formally an optimization problem: finding the highest possible inputs that will

still satisfy the given environmental targets. In practice, a pragmatic approach needs to be

Page 7 of 22

used to solve the mathematical problem. The model is run from present day conditions long

enough into the future so that it is absolutely certain that the Baltic Sea is in balance with

imposed nutrient inputs (125 years), thereafter averaged indicator values are calculated from

an additional 75 years of simulation. By running the model with different combinations of

nutrient inputs a database of indicator values and associated inputs is created. From the

database complex, pressure-response relationships are established and these are used to

find MAI, as well as to assess the sensitivity of MAI to various sources of uncertainty. For

basins without additional reduction requirements, the 1997-2003 normalized averaged inputs

obtained from the PLC 5.5 project are used as MAI.

BNI results show that the optimal MAI can be estimated by first considering inputs and target

fulfilment in the Baltic Proper, Gulf of Riga and Gulf of Finland and thereafter in the remaining

four main sub-basins.

The basin-wise MAI, as presented in Table 3 (cf. Table 9.1 in the Annex), are obtained by

satisfying all targets in all basins, with a few exceptions, of which the most important ones

are:

1 Nitrogen input reductions were not considered necessary to the Bothnian Bay and

Gulf of Riga because of extremely strong phosphorus limitations of the ecosystem in

these basins (resulting in a situation where DIN targets are not fulfilled)

2 A less strict application of the targets in the Gulf of Finland by applying the so-called

HEAT approach

on winter nutrient concentration

3 Model bias on phosphorus in the Bothnian Bay made it impossible to use the winter

phosphorus (DIP) target for this basin.

Table 3. Maximum Allowable nutrient Inputs to main Baltic Sea sub-basins. Values that represent reductions compared

with reference inputs (1997-2003) are highlighted by italics.

Maximum Allowable Inputs

Baltic Sea sub-basin

Kattegat

Danish Straits

Baltic Proper

Bothnian Sea

Bothnian Bay

Gulf of Riga

Gulf of Finland

Baltic Sea

Total nitrogen, tonnes

74,000

65,998

325,000

79,372

57,622

88,417

101,800

792,209

Total phosphorus, tonnes

1,687

1,601

7,360

2,773

2,675

2,020

3,600

21,716

4 H

OW ARE THE UPDATED

CART

WAS DETERMINED

4.1 Establishing a complete dataset on air- and waterborne inputs to the Baltic Sea

The data set on nutrient inputs to the Baltic Sea has significantly improved in most aspects

since BSAP 2007.

•

The HELCOM PLC data set, now covering 1994-2010, has been revised and

updated, data gaps have been filled in, some data have been corrected and the

dataset quality has been assured as far as possible. This has resulted in a more

complete and consistent dataset (PLC-5.5 project). Use of flow normalized riverine

data and climate normalized airborne deposition data before calculating average

water- and airborne inputs during the reference period, as compared with using a

simple average of non-normalized water and airborne inputs from 1997-2003 in

BSAP 2007. Normalization creates time-series with strongly reduced variability

caused by annual weather and river flow variations.

Page 8 of 22

•

Air emission data, the meteorological and the chemical model used for deposition

modelling have all been improved, resulting in revised annual deposition data.

The reference inputs are defined as the average of normalized airborne and flow normalized

waterborne inputs of nitrogen and phosphorus per country and per basin in the reference

period 1997-2003. The inputs are compiled in Table 9.5 and Table 9.6 for total nitrogen and

total phosphorus, respectively (cf. Annex).

4.2 Transboundary inputs

4.2.1

Waterborne inputs from non-Contracting Parties

Estimates of waterborne nutrient inputs entering the Baltic Sea are based on monitoring at

the river mouth. For some rivers, a share of the nutrient inputs originates from catchment

areas upstream of the country bordering the sea. Such inputs are called transboundary

inputs, and can originate from both non-Contracting Parties and HELCOM countries. A part

of these transboundary inputs never enter the Baltic Sea due to retention in the surface

waters in the receiving HELCOM countries. In principle, the HELCOM countries receiving

transboundary inputs should not be accounted for these shares.

Net transboundary inputs from non-Contracting Parties in most cases constitute only small

percentages (1-6%) of the waterborne nutrient inputs entering the Baltic Proper from Poland

and Lithuania (Table 9.8), but constitute more than 40% of the total waterborne phosphorus

input to the Gulf of Riga from Latvia. In Table 9.8 of the Annex, the net transboundary inputs

from non-Contracting Parties have been estimated.

The potential reductions in these transboundary inputs have been estimated assuming the

same level of ambition as for HELCOM countries (cf. section 4.4).

4.2.2

Waterborne inputs from HELCOM countries

For two border rivers (Torne Älv and Narva) the countries sharing the waterborne inputs

have agreed in advance on a percentage division of these rivers.

However, there are five country-by-basin catchments where upstream HELCOM countries

contribute to the waterborne inputs:

•

Lithuania contributes to the waterborne inputs from Latvia to the Baltic Proper,

•

Poland contributes to Russian waterborne inputs to the Baltic Proper,

•

Germany contributes to Polish waterborne inputs to the Baltic Proper,

•

Lithuania and Russia contribute to the waterborne inputs from Latvia to the Gulf of

Riga, and

•

Finland contributes to the waterborne inputs from Russia to the Gulf of Finland.

The net waterborne inputs from these upstream catchment areas are summarised in Table

9.8 in the Annex. Using these net waterborne inputs the reduction burden can be shared

between HELCOM countries.

4.2.3

Airborne inputs from outside HELCOM countries

EMEP has estimated the potential reduction in nitrogen deposition due to national NOx and

emission reduction commitments for 2020 under the Gothenburg Protocol. This includes

quantification of the decrease in nitrogen deposition per sub-basins resulting from the

decrease of emissions from non-Contracting Parties. These figures make it possible to follow

up on the development in relation to expected reductions from non-Contracting Parties due

to these regulatory frameworks. The results are presented in Table 4.

In addition, the implementation of the NOx Emission Control Area for shipping would

significantly reduce the emissions from shipping (80%) by 2030.

Page 9 of 22

Table 4. Modelled reduction in atmospheric deposition of nitrogen (tonnes) by 2020 as compared with deposition in the

reference period due to emission reduction commitments under the Gothenburg Protocol as calculated by EMEP.

“EU20” is non-HELCOM EU countries (including Croatia) and “other sources” are all other non-Contracting countries

and sources contributing to nitrogen deposition, including Baltic Sea shipping.

Source

HELCOM countries

"EU20"

Other sources

All sources

BOB

1,396

642

167

2,205

BOS

3,999

2,242

606

6,847

BAP

20,059

12,917

1,808

34,784

GUF

1,816

1,093

393

3,302

GUR

1,393

955

254

2,602

4,120

2,741

6,871

KAT

3,730

2,482

6,241

BAS

36,513

23,072

3,267

62,854

For the whole Baltic Sea, the reduction in atmospheric nitrogen deposition in 2020 (as

compared to the level in the reference period 1997-2003) is estimated to be nearly 63,000

tonnes from all deposition sources; of which nearly 60% (more than 36,000 tonnes) is

reduction from HELCOM countries. The highest estimated nitrogen deposition reductions

from Contracting Parties are from Germany (12,600 tonnes), Denmark (8,700 tonnes) and

Poland (7,300 tonnes).

Approximately 13% of the reduction requirement to the Baltic Proper can be achieved by the

expected reductions from EU countries that are not HELCOM Contracting Parties, and for

Kattegat it amounts to about 52%.

There has already been a substantial decrease in airborne nutrient inputs from non-

Contracting Parties.

4.3 Steps for calculating country allocated reduction targets (CART)

The calculation of CART (allocation scheme) is described in simple

steps

below:

Establish reference data on country by sub-basin inputs including all sources (all riverine

inputs, coastal point sources discharging directly to the Baltic Sea and atmospheric

deposition) - table 9.5-9.7 in Annex.

Subtract atmospheric nitrogen deposition from non-HELCOM countries and ship traffic

and atmospheric phosphorus deposition on the Baltic Sea from the reference inputs to

each sub-basin

Calculate the share (%) of input from each country to each basin based on steps 1-2.

Calculate needed reduction per sub-basin by subtracting the reference inputs with the

Maximum Allowable Inputs (MAI).

Reduce the calculated needed reduction per sub-basin by the anticipated reduction of

nitrogen deposition from decreased emissions in non-Contracting Parties

(implementation of the Gothenburg Protocol) and from reduced shipping emissions

(implementation of NECA).

Obtain the country by basin allocation by multiplying the results from Step 5 with the

share computed in Step 3.

Where there are transboundary waterborne contributions from upstream countries, the

country by basin allocation is shared among these countries.

Page 10 of 22

As shown in figure 6, the needed reduction (see Figure 5) is multiplied by each HELCOM

country’s share of the reference input to the sub-basin (see Figure 4). In the example Poland

had 58% of the total reference water- and airborne input originating from HELCOM countries

to this sub-basin and therefore has 58% of the reduction requirement (right figure). For

HELCOM countries that receive transboundary inputs, a share of the reduction requirement

is calculated for each of the upstream countries, both HELCOM and non-HELCOM. To

obtain the final Country Allocated Reduction Targets the shares are added or subtracted to

each HELCOM country (see section 4.4).

4.4 Proposed CART

Based on the steps above, the updated CART are calculated for waterborne and airborne

inputs of nitrogen (Table 5) and phosphorus (Table 6) for countries and specific sub-basins.

In these tables the country by basin reduction requirement without deduction of

transboundary sharing is given, which may easily be compared with the annual PLC data set.

Further, the waterborne transboundary reduction shares (calculated with retention to the river

mouths) are singled out and the total country by basin reduction target is calculated. The

country-wise summaries comprise of the sums of the sub-basin-wise reduction (cf. rounded

figures in Table 1).

Table 5. Proposed country by basin allocation of nitrogen reductions CART (tonnes).

NITROGEN

Country by basin

reduction before

deducting

transboundary shares

Transboundary shares

CART

HELCOM

countries

non-HELCOM

countries

2,136

382

424

7,419

1,645

8,935

43,436

2,498

8,356

Denmark

Estonia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Gothenburg Protocol expected

reduction in non-Contracting

Parties

Expected reduction from

shipping

Belarus

Czech Republic

Ukraine

Sum

Denmark

Estonia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Gothenburg Protocol expected

reduction in non-Contracting

Parties

Expected reduction from

shipping

Sum

Baltic Proper

2,136

382

424

6,922

2,360

9,550

45,178

3,153

8,356

497

-715

715

158

-655

-1,330

-1,900

14,725

5,735

1,977

727

526

14,725

5,735

1,977

727

526

98,921

1,419

2,603

165

147

7,879

1486

592

14,452

98,921

Gulf of Finland

1,419

2,004

165

147

8,478

1486

592

14,452

599

-599

Page 12 of 22

Denmark

Estonia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Gothenburg Protocol expected

reduction in non-Contracting

Parties

Expected reduction from

shipping

Sum

Kattegat

708

826

2,511

602

4,761

708

826

2,511

602

4,761

Table 6. Proposed country by basin allocation of phosphorus reductions CART (tonnes).

PHOSPHORUS

Country by basin

reduction before

deducting

transboundary shares

Transboundary shares

HELCOM

countries

non-HELCOM

countries

CART

Denmark

Estonia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Belarus

Czech Republic

Ukraine

Sum

Denmark

Estonia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Sum

Denmark

Estonia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Belarus

Sum

Baltic Proper

111

171

1,671

7,810

609

535

-42

-128

-272

-397

10,960

Gulf of Finland

268

338

424

187

175

129

1,441

7,477

481

535

424

187

10,960

268

364

3,303

3,909

Gulf of Riga

270

-26

3,277

3,909

-56

-128

308

128

308

Page 13 of 22

4.5 Indication of reduction requirements on an air- and a waterborne part

The airborne and a waterborne part of CART can be illustrated using the proportion of

airborne to waterborne inputs during the reference period, and adding/subtracting the share

of waterborne transboundary inputs on the waterborne part. The results are shown in Table

4.4. As all atmospheric deposition of phosphorus is included as a part of the background

inputs there are no reduction requirements on the airborne phosphorus inputs for the

HELCOM countries.

Table 7. Illustration of HELCOM Contracting Parties nitrogen reductions requirements split into atmospheric and

waterborne parts for sub-basins.

Country/basin,

tonnes

Denmark

Estonia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Baltic Sea total

BAP

air

1,740

141

424

5,466

206

507

4,179

825

1,683

15,171

water

396

241

1,953

1,439

8,428

39,257

1,673

6,673

60,060

air

GUF

water

1,343

2,492

7,683

11,518

air

KAT

water

575

804

1,379

air

Total

water

971

1,584

2,492

1,953

1,439

8,428

39,257

9,356

7,477

72,957

111

165

147

196

856

133

269

1,915

217

537

5,710

230

541

4,353

1,025

1,768

16,296

5. P

ROGRESS

The trend and development in waterborne input from 1994 to 2010 and from the reference

period to 2008-2010 is tested and reported in

HELCOM PLC-5.5 extended summary report

(in press). From 1995 to 2010 there have been significant reductions of approximately 16%

on total airborne and waterborne nitrogen inputs to the Baltic Sea and approximately 18% of

the total phosphorus inputs, with some countries having even higher significant reductions

(up to 35% for nitrogen and 29% for phosphorus), but with one or two countries having

significant increases in nutrient inputs.

For sub-basins with reduction requirements according to table 9.1 (cf. Annex), there have

been reductions in total nitrogen and phosphorus inputs (except for the Gulf or Riga) since

the reference period to 2008-2010 (Figure 7). For Kattegat, the reduction in nitrogen inputs is

about 3 times higher than the reduction requirement. For the Baltic Proper and the Gulf of

Finland in 2008-2010 more than one third of the needed reduction requirement has been

obtained by 2008-2010, while for phosphorus the input reduction has been about 22-25% of

the required reduction. To the Gulf of Riga it seems as phosphorus inputs have increased

since the reference period.

Page 14 of 22

Figure 8. Time development of inorganic winter nutrient concentrations in the Baltic proper surface waters. The grey

bars with associated curves represent the case with inputs as in the reference period (1997-2003) during the whole

scenario, and the red represents inputs reduced to MAI by year 0. The thick lines are 11-years running average, thin

lines average of 10 realizations using different weather forcing and the grey and red bars indicate the range of natural

variability. The dotted line is the target.

Figure 9. Time development of nitrogen fixation in the

Gulf of Finland. The grey bars with associated curves

represents the case with inputs during all 30 years as in

the reference period and the red represents inputs

reduced to MAI by year 0. The thick lines are 11-years

running average, thin lines average of 10 realizations

using different weather forcing and the grey and red bars

indicate the range of natural variability.

After implementation of full input reductions,

it may take a long time before the Baltic Sea

reaches an equilibrium with the new inputs,

which is clearly seen, for example, in surface

winter nutrient concentrations in the Baltic

Proper (Figure 8). The intricate dynamics of nitrogen makes the path of winter DIN reduction

somewhat bumpy, contrary to the steady reduction of winter DIP.

But it is very important to

notice that significant improvements will be seen much more rapidly. For example, as

shown in

Figure 9,

already the first year after the implementation,

nitrogen fixation in the

Gulf of Finland will decrease with almost 20% and a decade after implementation the higher

end of natural variability in nitrogen fixation, indicating risk of cyanobacteria blooms, will be

below present day average. Thus, we could quite soon anticipate seeing less summer

blooms.

6.2 Validity of the results of the revised BSAP nutrient reduction scheme figures

PLC-5.5 data set

The used PLC-5.5 data set of airborne and waterborne nutrient inputs to the Baltic Sea is the

most complete and consistent pollution input data set established so far within HELCOM.

The highest uncertainty of nutrient input data seems to apply to the Gulf of Finland and the

Gulf of Riga, but overall it is evaluated that the PLC-5.5 dataset gives rather robust results,

and further corrections on the data set would not give markedly different MAI and CART.

However, especially for phosphorus, it is possible that inputs from some big point sources

are not quantified at all, which would underestimate the reduction requirement and the share

of the reductions in the countries where these point sources are situated.

Page 16 of 22

Why not consider economy before MAI and CART are settled

The vision of HELCOM is to have a healthy sea. Eutrophication targets and nutrient

reduction schemes have been developed with natural science models, in order to calculate

optimized necessary nutrient reductions to the individual sub-basins needed to fulfill

eutrophication targets from an ecological viewpoint.

Economic cost-benefit models are relevant when evaluating and selecting among the palette

of nutrient reduction measures that could be identified, and where the most cost efficient

measures can be taken and implemented. Further, economical cost-benefit models are not

developed to determine the ecological optimal solutions for the Baltic Sea.

Uncertainty of the MAI and CART figures

The uncertainty of eutrophication status targets was not explicitly assessed by the

TARGREV project, however, targets have been ranked into groups according to their

confidence.

It is straightforward but laborious to explore how MAI varies with changes in target values

from the pressure-response relationships. The laborious aspect arises from the numerous

combinations of uncertainty that can arise if many indicator values and basins are

simultaneously taken into account. However, the impression is that the most challenging

target for most basins is nitrogen, as in most cases there are no, or only few, trustworthy

measurements to indicate the eutrophication situation in the early levels. Also, the

relationship between nitrogen input and concentrations in sea waters is rather weak in basins

featuring hypoxia, i.e., the Baltic Proper and the Gulf of Finland unless phosphorus input

reductions are so large that a strong phosphorus limitation occur.

In the calculation of MAI, it has been attempted to take biases in BALTSEM into account,

either by discarding indicators in basins were they are not adequately modelled, but also to

raise a concern whether MAI is really trustworthy because of model deficiency/bias. An

especially intricate example, still under investigation, is the Danish Straits.

NB: both MAI and CART calculations are affected by the input data to the model. If input data

are inconsistent, it may lead both to over- or underestimation of MAI and CART, and thus to

an unfair distribution of reduction requirement between countries.

The highest uncertainty regarding input data is in the calculation of the proportion of

transboundary waterborne input data entering the Baltic Sea, because there is a need to take

into account retention in surface waters in the countries receiving the transboundary input.

Despite much work done to model and estimate retention, these should still be seen as

rather rough averages for big catchments.

Finally it should be stressed that the calculated MAI are the minimum reduction requirement

to fulfill the eutrophication targets. They are derived for Baltic Sea open sea areas and they

are therefore not directly comparable with reduction targets derived for fulfilling targets in

coastal waters.

Implications of climate change on MAI, CART and needed measures

Recent findings indicate that climate change may reinforce effects from eutrophication and

thus increase the risk of not reaching the environmental targets. However, it is also clearly

shown that without curbing inputs the situation will deteriorate even further. In this

perspective, reducing nutrient inputs could be seen also as a precautionary measure against

the negative effects from climate change.

At present, scientific knowledge and tools are not in place to make a proper assessment of

MAI under the constraints of climate change. There is also another more fundamental

problem with addressing climate change and targets because climate change is inherently a

time-dependent process whereas the target definition is static. Thus, one needs either to set

a time-fixed goal (sensu the 2 degree by 2100 target for climate change) or make some sort

of adaptation with climate change so that one stays within targets despite changing

conditions. However, at present, the best foreseeable way to handle climate change issues is

to initiate a cyclical revision of MAI.

Page 17 of 22

7. R

EFERENCES

Gustafsson, B.G and Mörth, C.M. (in prep.). Revision of the Maximum Allowable Inputs and

Country Allocation Scheme of the Baltic Sea Action Plan V. 3 with contributions from the BNI

team: Bärbel Mïller-Karulis, Erik Gustafsson, Bonghi Hong, Christoph Humborg, Steve Lyon,

Marmar Nekoro, Miguel Rodriguez-Medina, Oleg Savchuk, Erik Smedberg, Alexander

Sokolov, Dennis Swaney, and Fredrik Wulff. Baltic Nest Institute, Stockholm University, SE-

106 91 Stockholm.

HELCOM 1992. Convention on the Protection of the Marine Environment of the Baltic Sea

Area, 1992 (Helsinki Convention). 48 pp.

HELCOM 2007a. HELCOM Baltic Sea Action Plan. Adopted in Krakow, Poland on 15

November 2007.

HELCOM, 2007b: An approach to set country-wise nutrient reduction allocation to reach

good ecological status of the Baltic Sea. Document 2.1/2 HELCOM HOD 22/2007, 34 pp.

HELCOM 2009. Eutrophication in the Baltic Sea – An integrated thematic assessment of the

effects of nutrient enrichment in the Baltic Sea region. Baltic Sea Environment Proceedings

No. 115B.

HELCOM 2013. Approaches and methods for eutrophication target setting in the Baltic Sea

region. Baltic Sea Environment Proceedings No. 133

HELCOM in prep. Update of 5

Pollution Load Compilation of water and airborne nutrient

inputs to the Baltic Sea 1994-2010 (PLC-5.5).

Larsen, S.E. and Svendsen, L.M. (in prep). Statistical aspects in relation to Baltic Sea

Pollution Load Compilation (task 1 under HELCOM PLC-6), Department of Bioscience and

DCE - Danish Centre for Environment and Energy, Aarhus University. Draft, 26 pp

HELCOM PLC-5.5 Extended Summary (in press). Svendsen et al. Extended Summary of

“Update of 5

Pollution Load Compilation of water and airborne nutrient inputs to the Baltic

Sea 1994-2010 (PLC-5.5)”.

Wulff F, Savchuk OP, Sokolov A, Humborg C & Mörth C-M 2007. Management options and

effects on a marine ecosystem: Assessing the future of the Baltic. Ambio 36 (2-3): 243-249.

Page 18 of 22

8. D

EFINITIONS

LOSSARY

Airborne

Anthropogenic

Atmospheric deposition

Border river

BSAP

Catchment area

Contracting parties

Country-Allocated

Reduction Targets (CART)

Diffuse sources

DIN and DIP

Direct Sources

Eutrophication

Flow normalization

HOLAS open sea sub-

basins

Input ceiling

Maximum Allowable Input

(MAI)

Monitored areas

Monitoring stations

Non-contracting parties

PLC

Point sources

Reference period

Reference input

Retention

Riverine inputs

Statistically significant

Nutrients carried or distributed by air.

Caused by human activities.

Airborne nutrients or other chemical substances originating from emissions to the air and deposited from the air

on the surface (land and water surfaces).

A river that has its outlet to the Baltic Sea at the border between two countries. For these rivers, the inputs to the

Baltic Sea are divided between the countries in relation to each country’s share of total input.

Baltic Sea Action Plan.

The area of land bounded by watersheds draining into a body of water (river, basin, reservoir, sea).

Signatories of the Helsinki Convention (Denmark, Estonia, European Commission, Finland, Germany, Latvia,

Lithuania, Poland, Russia and Sweden).

Country-wise requirements to reduce waterborne and airborne nutrient inputs (in tonnes per year) to reach the

maximum allowable nutrient input levels in accordance to the Baltic Sea Action Plan.

Sources without distinct points of emission e.g. agricultural and forest land, natural background sources,

scattered dwellings, atmospheric deposition (mainly in rural areas)

Dissolved inorganic nitrogen and dissolved inorganic phosphorus compounds.

Point sources discharging directly to coastal or transitional waters.

Condition in an aquatic ecosystem where increased nutrient concentrations stimulate excessive primary

production, which leads to an imbalanced function of the ecosystem.

A statistical method that adjusts a data time series by removing the influence of variations imposed by river flow,

e.g. to facilitate assessment of development in e.g. nitrogen or phosphorus inputs.

Open sea areas not affected by coastal dynamics. Bothnian Bay, Bothnian Sea, Åland and Archipelago Sea,

Northern Baltic Proper, Gulf of Finland, Western Gotland Basin, Eastern Gotland Basin, Gulf of Riga, Gulf of

Gdansk, Bornholm Basin, Arkona Basin, Kiel and Mecklenburg Bight, Belt Sea, Kattegat

The allowable amount of nitrogen and phosphorus input per country and sub-basin. It is calculated by subtracting

the CART from the input of nitrogen and phosphorus during the reference period of the BSAP (1997-2003).

The maximum annual amount of a substance that a Baltic Sea sub-basin may receive and still fulfill HELCOM’s

ecological objectives for a Baltic Sea unaffected by eutrophication.

The catchment area upstream the river monitored point. The chemical monitoring decides the monitored area in

cases where the locations of chemical and hydrological monitoring stations do not coincide.

Stations where hydrographic and/or chemical parameters are monitored.

Countries that are not partners to the Helsinki Convention 1992, but that have an indirect effect on the Baltic Sea

by contributing with inputs of nutrients or other substances via water and/or air.

Baltic Sea Pollution Load Compilation

Municipalities, industries and fish farms that discharge (defined by location of the outlet) into monitored areas,

unmonitored areas or directly to the sea (coastal or transitional waters).

1997-2003

The average normalized water + airborne input of nitrogen and phosphorus during 1997-2003 used to calculate

CART and input ceilings.

The amount of a substance lost/retained during transport in soil and/or water including groundwater from the

source to a recipient water body. Often retention is only related to inland surface waters in these guidelines.

The amount of a substance carried to the maritime area by a watercourse (natural or man-made) per unit of time.

In statistics, a result is called "statistically significant" if it is unlikely to have occurred by chance. The degree of

significance is expressed by the probability, P. P< 0.05 means that the probability for a result to occur by chance

is less than 5%.

Subdivision units of the Baltic Sea. Kattegat (KAT), Belt Sea (BES), Western Baltic (WEB), Baltic Proper (BAP),

Gulf of Riga (GUR), Gulf of Finland (GUF), Archipelago Sea (ARC) Bothnian Sea (BOS) and Bothnian Bay

(BOB).

Transport of an amount of a substance (via air or water) across a country border.

Total nitrogen and total phosphorus which includes all fractions of nitrogen and phosphorus.

Any sub-catchment(s) located downstream of the (riverine) chemical monitoring point within the catchment and

further all unmonitored catchments. It includes also the coastal areas, which have been used in former version of

the guidelines.

Substances carried or distributed by water.

Sub-basins

Transboundary input

TN and TP

Unmonitored area

Waterborne

Page 19 of 22

9. T

ECHNICAL

NNEX

The Technical Annex contains data tables used in calculation of Maximum Allowable Inputs

and Country Allocated Reduction Targets.

Table 9.1. Needed reductions for total nitrogen (TN) and total phosphorus (TP) in individual sub-basins of the Baltic

Sea in comparison to Maximum Allowable Inputs and nitrogen and phosphorous inputs in the reference period (1997-

2003).

Maximum Allowable Inputs

Reference inputs

Needed reductions

tonnes

Kattegat

74,000

1,687

78,761

1,687

4,761

Danish Straits*

65,998

1,601

65,998

1,601

Baltic Proper

325,000

7,360

423,921

18,320

98,921

10,960

Bothnian Sea*

79,372

2,773

79,372

2,773

Bothnian Bay*

57,622

2,675

57,622

2,675

Gulf of Riga

88,417

2,020

88,417

2,328

308

Gulf of Finland

101,800

3,600

116,252

7,509

14,452

3,909

Baltic Sea

792,209

21,716

910,343

36,893

118,134

15,177

See the text in the Ministerial Declaration concerning need for addition actions to reduce nutrients also in basins

without reduction targets.

Baltic Sea Sub-basin

Table 9.2. HELCOM

targets for nutrients (in μmol l

−1

), summer chlorophyll a (in μg l

−1

) and summer Secchi depth (m) for

the Baltic Sea HOLAS open sea sub-basins. Winter means are December-February and summer means are June-

September.

Basin

Kattegat

The Sound

Great Belt

Little Belt

Kiel Bay

Bay of Mecklenburg

Gdansk Basin

Arkona Sea

Bornholm Sea

Eastern Gotland Basin

Western Gotland Basin

Northern Baltic Proper

Gulf of Riga

Gulf of Finland

Åland Sea

Bothnian Sea

The Quark

Bothnian Bay

Winter DIN

5.0

3.3

5.0

7.1

5.5

4.3

4.2

2.9

2.5

2.6

2.0

2.9

5.2

3.8

2.7

2.8

3.7

5.2

Winter DIP

0.49

0.42

0.59

0.71

0.57

0.49

0.36

0.30

0.29

0.33

0.25

0.41

0.59

0.21

0.19

0.10

0.07

Summer Chl

1.5

1.2

1.7

2.8

2.0

1.8

2.2

1.8

1.9

1.2

1.7

2.7

2.0

1.5

2.0

Summer Secchi depth)

7.6

8.2

8.5

7.3

7.4

7.1

6.5

7.2

7.1

7.6

8.4

7.1

5.0

5.5

6.9

6.8

6.0

5.8

In addition to the eutrophication targets listed in table 2.1 oxygen debt targets have been

agreed:

•

Gotland Sea and Gulf of Finland: 8.66 mg l

-1

•

Bornholm Basin: 6.37 mg l

-1

•

and on oxygen concentration >2 mg l

-1

in Danish Straits and Kattegat

Page 20 of 22

Table 9.3. HELCOM eutrophication status targets for 18 HELCOM open sea areas (Table 9.2) were aggregated into

seven-basins that MAI are calculated on by an area-weighted average for all variables. Winter means are December-

February and summer means are June-September.

Basin

Kattegat

Danish Straits

Baltic Proper

Bothnian Sea

Bothnian Bay

Gulf of Riga

Gulf of Finland

Winter

DIN (μmol l

−1

)

5.0

2.6

2.8

5.2

3.8

Winter

DIP (μmol l

−1

)

0.49

0.56

0.30

0.19

0.07

0.41

0.59

Summer

Chl

(μg l

−1

)

1.5

1.9

1.7

1.5

2.0

2.7

2.0

Summer

Secchi (m)

7.6

7.8

7.4

6.8

5.8

5.0

5.5

Table 9.4. Waterborne reference inputs (tonnes) used in BSAP 2007 and the new waterborne and airborne reference

inputs used for calculating the new nutrient reduction requirements to the Baltic Sea (in BSAP 2007 reference

atmospheric input was approx. 280,000 tonnes nitrogen and 6,300 tonnes phosphorus).

Basins/ inputs in

tonnes

Kattegat

Danish Straits

Baltic Proper

Bothnian Sea

Bothnian Bay

Gulf of Riga

Gulf of Finland

Baltic Sea total

BSAP 2007 waterborne

reference inputs

Total N

Total P

64,257

1,573

45,893

1,409

327,259

19,246

56,786

2,457

51,436

2,585

78,404

2,180

112,680

6,860

736,714

36,310

New reference waterborne

inputs

Total N

Total P

58,484

1,569

41,605

1,496

297,679

17,274

54,605

2,379

49,437

2,494

78,373

2,235

102,919

7,359

683,102

34,807

New reference airborne

inputs

Total N

Total P

20,277

118

24,393

105

126,243

1,046

24,767

394

8,185

181

10,045

13,333

150

227,242

2,087

In Table 9.5, atmospheric input from the Contracting Parties included in the total inputs to the

sub-basins, while nitrogen deposition from non-Contracting Parties (in total 85,500 tonnes

nitrogen) and shipping on the Baltic Sea (in total nearly 11,900 tonnes nitrogen) to the main

sub-basin is shown separately. In Table 9.7 the normalized deposition of atmospheric

nitrogen deposition in the reference period is shown. Phosphorus deposition on the Baltic

Sea (ca. 2,100 tonnes phosphorus) cannot be allocated to any country and is therefore given

in a separate row in Table 9.6.

Table 9.5. Total country by basin normalized nitrogen inputs to the Baltic Sea during the reference period 1997-2003.

“Baltic Shipping” is shipping within Baltic Sea, “EU 20 atm” is atmospheric deposition from non Contracting Parties

EU countries (including Croatia) and “other countries” are deposition from other non-Contracting Parties and other

sources on the Baltic Sea sub-basins.

Country/Basin

Denmark

Estonneia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Other atm. sources

Baltic Shipping

EU 20 atm.

Baltic Sea

BOB

226

34,389

801

108

631

696

17,571

1,090

361

1,595

57,622

BOS

854

299

27,978

2,994

258

464

2,647

1,465

31,502

3,793

1,461

5,658

79,372

BAP

10,046

1,795

1,993

32,554

11,100

44,920

212,486

14,831

39,299

15,278

7,169

32,449

423,921

GUF

376

12,683

17,903

1,477

206

294

1,313

75,754

565

2,166

739

2,775

116,252

GUR

374

12,777

250

1,437

66,284

437

1,335

510

440

1,572

561

2,441

88,417

28,587

20,708

1,061

164

5,870

1,958

826

6,673

65,998

KAT

30,027

3,364

1,133

178

35,032

2,152

751

5,938

78,761

Total

70,490

27,684

82,652

63,335

77,959

46,335

220,606

93,598

130,279

28,009

11,868

57,528

910,343

Page 21 of 22

Table 9.6. Total country by basin normalized phosphorus inputs to the Baltic Sea during the reference period 1997-

2003. “Atm. Dep” is atmospheric deposition of phosphorus on the Baltic Sea.

Country/Basin

Denmark

Estonia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Atm. dep.

Baltic Sea

BOB

1,668

826

181

2,675

BOS

1,255

1,125

394

2,773

BAP

175

269

2,635

12,310

960

843

1,046

18,320

GUF

504

637

6,218

150

7,509

GUR

277

1,958

2,328

1,040

351

105

1,601

KAT

829

740

118

1,687

Total

1,928

804

3,560

526

2,227

2,635

12,310

7,178

3,639

2,087

36,893

Table 9.7. Total country by basin normalized atmospheric nitrogen deposition during the reference period 1997-2003.

“Baltic Shipping” is shipping within Baltic Sea, “EU 20 atm” is atmospheric deposition from non HELCOM Contracting

Parties EU countries (including Croatia) and “other countries” are deposition from other non-Contracting Parties on

the Baltic Sea sub-basins.

Country/Basin

Denmark

Estonia

Finland

Germany

Latvia

Lithuania

Poland

Russia

Sweden

Other countries

Shipping

EU 20 atm.

Baltic Sea

BOB

226

1,764

801

108

631

696

758

1,090

361

1,595

8,185

BOS

854

299

2,337

2,994

258

464

2,647

1,465

2,537

3,793

1,461

5,658

24,767

BAP

8,182

661

1,993

25,708

967

2,384

19,655

3,881

7,916

15,278

7,169

32,449

126,243

GUF

376

680

994

1 477

206

294

1 313

1 748

565

2,166

739

2,775

13,333

GUR

374

247

250

1 437

441

437

1 335

510

440

1,572

561

2,441

10,045

5,311

7,865

1,061

164

384

1,958

826

6,673

24,393

KAT

5,635

3,364

1,133

178

941

2,152

751

5,938

20,277

Total

20,958

2,017

7,476

43,646

1,983

3,799

27,774

8,642

13,541

28,009

11,868

57,528

227,243

Table 9.8. Transboundary riverine inputs (in tonnes yr

-1

) from HELCOM countries and non-Contracting Parties used in

the CART calculations. Retention coefficient is from table 9.4 in Gustafsson and Mörth (in prep). All data are averaged

1997-2003 except for the Belarusian data which are averaged 2004-2011. Input at the border is multiplied with the

retention coefficient to estimated net waterborne input to the Baltic Sea. “Share of inputs” is - expressed in percentage

- how big proportion of the total input at the river mouth originates from the non-contracting Party.

From

Via

Border

tonnes

5,700

13,600

4,124

5,071

8,532

5,516

4,400

410

914

127

331

1,360

158

320

Retention

To Baltic

tonnes

3,420

6,256

2,474

3,043

15,193

6,228

3,365

3,080

2.337

8,782

5,245

1,957

7,202

5,353

295

430

238

1,055

925

202

101

369

192

215

407

Share of input

(%)

1.1

2.1

0.8

1.0

5.1

7.9

1.1

1.0

0.8

3.0

6.7

2.5

9.2

5.2

1.7

2.5

0.5

1.4

6.1

41.4

0.4

1.2

0.6

2.1

8.6

9.6

18.2

0.7

From non-Contracting Parties:

Czech

Poland

Belarus

Lithuania

Ukraine

Poland

Belarus

Poland

Total

Belarus

Latvia

Between Contracting Parties

Lithuania

Latvia

Poland

Russia

Germany

Poland

Total

Lithuania

Russia

Total

Finland

Latvia

Russia

BAP

GUR

BAP

GUR

GUF

0.4

0.54

0.4

0.27

0.39

0.30

0.28

0.53

0.28

0.32

0.58

0.37

7,185

4,256

282

734

0,27

0,54

0.48

0,32

0,71

0.82

Page 22 of 22