Ammonia emissions from UK agriculture the NARSES model

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TFEIP Workshop, Thessaloniki, Greece, 30-31
October 2006
Ammonia emissions from UK agriculture the
NARSES model
Tom Misselbrook IGER, North Wyke, UK
Imperial College
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Introduction

• Inventory model for a major emission source -
  NARSES as an example
• Detailed partial emission factors (incl.
  process-based)
• Detailed activity data
• Spatial and temporal disaggregation
• Introduction of abatement measures
• Cost curve development
• Mapped output

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NARSES

• National Ammonia Reduction Strategy Evaluation
  System
• Ammonia emissions from UK agriculture gt80
  total UK emission
• Replaces old-style UK ammonia emissions
  inventory
• Nitrogen flow model, mass-conservative
• EF now expressed as of available N rather than
  fixed units

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Ammonia sources
1. Nitrogen fertiliser applications
EF
NH3
Emission fn (fertiliser type, land use,
temperature, rainfall, soil pH) Monthly
time-step Fertiliser types associated with
different potential emissions Activity data from
British Survey of Fertiliser Practice
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Ammonia sources
2. Nitrogen excretion by livestock
measures
grazing
Total N (RAN)
NH3
yards
NH3
NH3
NH3
NH3
storage
housing
spreading
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Emission factors
All expressed as RAN in the emission pool
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Activity data

• Data sources
• June agricultural census (livestock numbers)
• Farm practice surveys
• Ad-hoc surveys
• Expert opinion

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Technical measures
For each potential abatement technique Emis
sion reduction efficiency Applicability Curr
ent implementation Cost
e.g. shallow injection 70 80? 1 2.40 per
m3 slurry
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NARSES Model 8 Sectors, 269 Nodes, 349 Links,
162 Measures
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Operates at 10 x 10 km grid Cost-curve
optimisation
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Model developments

• Increasingly link EF to environmental and
  management variables
• Include links with N2O emission and NO3 leaching
  models
• Include front-end linking diet with N excretion

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Projections

• NARSES a robust model for making projections
• Defines key parameters which need to be
  surveyed/estimated
• Accounts for bulk changes in livestock numbers
• Also accounts for management changes policy,
  environment or market forces

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Projections Dairy cows
UK milk production to stay the same Cow numbers
declining, increasing milk yield per
cow Increasing N excretion per cow
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Projections Pigs and poultry
Implementation of IPPC No change in livestock
numbers
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Summary

• To make robust projections
• Sufficient level of detail within model
• EF linked to environmental and management
  variables
• Ability to gather activity data at sufficient
  level
• Ability to predict changes in key management and
  environmental variables

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THANK YOU!