Wolfgang Sch

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Wolfgang Schöpp
The RAINS model Ecosystems impacts
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Modelling ecosystems impactsApproach

• Computed deposition of SN compared with critical
  loads estimates
• For acidification and eutrophication
• For different ecosystem types
• For individual grids or on country-bases
• For ex-post evaluation or for setting targets for
  optimization
• Evaluation of dynamic acidification processes
• Ex-post evaluation
• Comparison of computed ozone concentrations with
  critical levels
• For forest trees
• Flux approach for crops not (yet) implemented in
  RAINS, performed in context of benefit assessment

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Reducing deposition below the critical loadsAn
example for a French ecosystem
Slide prepared by Les White
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Reducing deposition below the critical loadsAn
example for a Spanish ecosystem
Slide prepared by Les White
Slide prepared by Les White
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Excess of critical loads at forests2000
Percentage of forest areawith acid deposition
above critical loads, using ecosystem-specific
deposition, Average of calculations for 1997,
1999, 2000 2003 meteorologies
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Percent of forest area with acid deposition
above critical loads
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Excess of critical loads at semi-natural
ecosystems including HABITAT areas, 2000
Percentage of area of semi-natural
ecosystemswith acid deposition above critical
loads, using ecosystem-specific deposition.
Average of calculations for 1997, 1999, 2000
2003 meteorologies
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Excess of critical loads of freshwater bodies2000
Percentage of catchments area with acid
deposition above critical loads, using
ecosystem-specific deposition. Average of
calculations for 1997, 1999, 2000 2003
meteorologies
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Excess of critical loads for eutrophication 2000
Percentage of ecosystems area with nitrogen
deposition above critical loads, using
grid-average deposition. Average of calculations
for 1997, 1999, 2000 2003 meteorologies
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Use of dynamic soil acidification models

• Critical loads reflect steady-state conditions
• Dynamic aspects important
• Recent progress in dynamic modelling for
  acidification, but not for eutrophication
• Are models and data good enough to be used?

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Use of dynamic modelling in RAINS

• No dynamic estimates available for many
  ecosystems in Europe
• For the ecosystems with data available, ex-post
  evaluation for emission control scenarios
  possible
• Use as optimization targets problematic due to
  missing estimates
• Historic base cation deposition important, but
  not modelled.

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Modelling of deposition

• Experiments with EMEP Eulerian model established
  general linearity
• However, co-deposition of S/NH3 identified
• Small effect on grid-average, thus ignored for
  first approach
• Importance for ecosystem-specific deposition
  estimates will be further evaluated.

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Response of total S depositiondue to changes in
UK SO2 emissions

• Linear response of S deposition
• over full range of SO2 emissions
• Minor impacts of other emissions

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Response of total S depositiondue to changes in
UK NH3 emissions

• S deposition depends on NH3 levels
• Especially at high NH3 levels
• But limited magnitude!

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Response of total S depositiondue to changes in
all UK emissions

• S deposition responds linearly
• if all other emissions are reduced
  simultaneously

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Conclusions

• Use of accumulated excess deposition for
  different ecosystems in Europe as a summary
  measure
• Results from dynamic models can be used as an
  ex-post analysis or for setting targets for the
  RAINS optimization
• Deposition of pollutants can be described with
  linear source-receptor relationships