Calculation of water quality targets in the south...
Transcript of Calculation of water quality targets in the south...
Calculation of water quality targets in the south-western Baltic Sea on the edge of WFD and MSFD
René Friedland T. Neumann, G. Nausch, N. Wasmund,
G. Schernewski (IOW & Klaipeda University)
20.01.2016, Brussels
Coastal waters: national responsibility Water Framework Directive (WFD)
Open sea waters: HELCOM’s responsibility Marine Strategy Framework Directive (MSFD)
State Agencies of
Federal states
German
Environmental Agency
Commonalities
• Aim: Good Ecological State (GES)
• Defined via thresholds (“target values”)
• Based on „reference conditions“
• Nutrient load reductions
as only measure
very good
good
moderate
Reference Value
Target Value
good
bad
Target Value
WFD MSFD
…
Workshop, IOW, Warnemünde, 29.08.2011 (GS) ......Symposium on inshore waters, LUNG Güstrow, 13.09.2012 (GS)
Workshop, LUNG, Güstrow, 14.09.2012 (GS)1. UAG Nährstoffreduktionsziele & Eutrophierung Baltic Sea, BSH, Hamburg, 15.11.2012 (GS)
HELCOM climate change workshop, IOW, 05.02.2013 (GS, RF) 2. UAG Nährstoffreduktionsziele & Eutrophierung Baltic Sea, IOW, 06.02.2013 (GS, RF)
Mini-Symposium "Marine Monitoring", LLUR Flintbek, 19.03.2013 (GS) 3. UAG Nährstoffreduktionsziele & Eutrophierung Baltic Sea, BSH Hamburg, 26.03.2013 (GS) 4. UAG Nährstoffreduktionsziele & Eutrophierung Baltic Sea, LUNG Güstrow, 28.10.2013 (GS, RF)
Symposium on inshore waters, LUNG Güstrow, 20.11.2013 (RF) 5. UAG Nährstoffreduktionsziele & Eutrophierung Baltic Sea, LUNG Güstrow, 13.02.2014 (GS, RF)
Mini-Symposium "Marine Monitoring", LLUR Flintbek, 26.03.2014 (GS) Symposium on marine environment, BSH Hamburg, 03.06.2014 (RF)
AG Nährstoff-Referenz- und Orientierungswerte North Sea, BSH Hamburg, 08.07.2014 (GS) 6. UAG Nährstoffreduktionsziele & Eutrophierung Baltic Sea, BSH Hamburg, 15.09.2014 (RF)
Symposium on inshore waters, LUNG Güstrow, 19.11.2014 (RF) Mini-Symposium "Marine Monitoring", LLUR Flintbek, 05.03.2015 (GS)
Fach-AG „Eutrophierung, Nährstoffe und Plankton“, DWD Hamburg, 14.07.2015 (RF) AG ‚Water quality targets North Sea‘…….
2011
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2012
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2013
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2014
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2015
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Joint BLANO working group with all involved agenciesInformal workshop
Public discussion organized by agencies
Join
t p
roje
ctIn
ad
van
ce o
f a
pro
ject1. Informal workshops
2. Joint working group (with a pre-defined work order by BLANO)
3. Public discussions
4. Joint scientific project (funded by BMBF)
5. Scientific paper (in English)
6. Joint extensive report (in German)
Eutrophication
parameters:
surface
concentrations of
Chlorophyll a,
Total Nitrogen &
Phosphorus
-> Secchi Depth is
missing First assessment (2009):
43 of 44 German water bodies not in GES
Review of present targets:
purely salinity dependent
with one target for every water type
Targets for Chlorophyll:
2 levels
intercalibrated for open coastal waters (GER, DK, PL)
0
50
100
150
200
250
0
5
10
15
20
25
Oder (River) Small Bayof Oder Lagoon
SouthernPomeranian Bight
Arkona Sea(HELCOM)
Target [µmol/l] State [µmol/l]
Total Nitrogen (annual average)
TN & TP targets unreachable (no motivation to start measures)
due to unrealistic ‘pristine’ loads of Oder
Used loads by Brockmann et al. (2012): 3.669 t TN /a (244 t TP/a)
Historical loads from Gadegast et al. (2012): 13.425 t TN/a (950 t TP/a)
Present loads [2000-09]: 55.000 t/a (3.200 t TP/a)
New approach necessary!
Demands:
Reachable & realistic reference conditions and target values
Chlorophyll targets in agreement with intercalibrated values
Singular approach for nutrients, Chlorophyll & Secchi Depth
Harmonized targets for coastal waters and open sea
Natural gradients from emission sources to open sea considered
How to define reference conditions/ values?“high status with no, or very minor disturbance from human activities”
1. Use observations from 1960s
2. Calculations based on
‘pristine conditions’
3. Assume realistic historic situation
(e.g. around 1880) & use an model
to calculate targets
Sparse in space & time
Not consistent with WFD
lack of knowledge and data
high uncertainties
worth pursuing?
Most reliable
Consistent with WFD & MSFD
Model errors to be considered
1880 as reference condition
• We go back as far as possible and reliable
• Land usage documented & comparable with today
• basis for a realistic & reachable ecological state
17% of present loads
22% of present loads
Figures provided by J. Mahnkopf (IGB)
• German loads & Oder from catchment model MONERIS
• Baltic Sea wide load reconstruction from BNI
• Ignore changes in the ecosystem (e.g. macrophytes)
How to deal with the model`s
uncertainty?
Simulated Chlorophyll Present
loads
Historical loads
measure for the specific reaction to the different loads
historical / present simulated chlorophyll
TP (annual)
TN(annual)
Chlorophyll (summer)
Always
steep gradients!
0
0,5
1
1,5
2
2,5
Present State Reference Value Proposed Target Present Target
Ch
loro
ph
yll a
[µ
g/l
]
Station O5
+ 50%(following
WFD guidance)
Multiplication with ratio from
simulation (0.6)
historical / present simulated chlorophyll Fits with intercalibrated target
Natural gradients are reproduced!
intercalibratedtargets
reproduced
new targets reflect local characteristics
stronger
new targets fit with present
ones
0
100
200
Oder (River) Small Bayof Oder Lagoon
SouthernPomeranian Bight
Arkona Sea(HELCOM)
Tota
l Nit
roge
n [
µm
ol/
l] Present target
State
new proposed target
Reachable & realistic
All defined demands fulfilled
Demands:
Reachable & realistic reference conditions and target values
Chlorophyll targets in agreement with intercalibrated values
Singular approach for nutrients, Chlorophyll & Secchi Depth
Harmonized targets for coastal waters and open sea
Natural gradients from emission sources to open sea considered
Reference values fit with historical observations
• Chlorophyll at Kiel Bay from 1905/06
• Secchi Depth at Bay of Greifswald and Small Bay of Szczecin Lagoon
1,28
0,60
2,52
(2,5)
2,632,82
0
1
2
Bay of Greifswald Szczecin Lagoon (Small Bay)
Sum
me
r Se
cch
i De
pth
[m
]
present state historical value (from literature) integrated model
Review of ecological state & targets
Modifying targetsImplementation
of measures
• Statistical attempt to link loads (TN & TN/TP-ratio) to CHL.a(averaged for the south-western BS, including parts of DK & PL)
• Result: TN-load reduction of 34% necessary (to decrease Chlorophyll-conc. by 20%)
• Assuming full implementation of Gothenburg Protocol
Total N [t/a]Atmospheric
TN [t/a]Waterborne
TN [t/a]River conc.TN [mg/l]
Total P [t/a]
Chl.a[µg/l]
1997-2003 (PLC 5.5)
32.697 13.007 19.690 4,7 526 4,5
Allowable German Loads
21.477 10.406 11.072 2,6 526 3,6
New proposed target for German river loads
BSAP (2013) 29.640 11.900 17.740 4,3 356 4,2
TN-load reduction of BSAP not sufficient for coastal waters!
Target: river loads
Good ecological state of the Baltic Sea
Management: catchment area
Target: inner coastal waters
Target: outer coastal waters
German environmental agencies
Research Institutes
René Friedland (IOW), G. Schernewski (IOW & KU), G. Nausch, T. Neumann, N. Wasmund (IOW),
W. Leujak (UBA), T. Petenati (LLUR), M. v. Weber (LUNG), M. Venohr, M. Gadegast, J. Mahnkopf (IGB)
Supercomputing power was provided by North-German Supercomputing Alliance:
Work was financed by: