Nitrogen deposition on regional and global scales:
a multi-model evaluation F.J. Dentener1, J. Drevet2, D.S. Stevenson3, K. Ellingsen4, T.P.C. van Noije5, M.G. Schultz6, C.S. Atherton7, N. Bell8, T. Butler9, B. Eickhout10, A.M. Fiore11,
J. Galloway12, C. Galy-Lacaux13, U.C. Kulshresta14, J.-F. Lamarque15, V. Montanaro16, J.-F. Müller17, J.M. Rodriguez18, M.G. Sanderson19, N.H. Savage20, S. Szopa21,
K. Sudo22, O. Wild22, G. Zeng20
1. JRC, Ispra, Italy. 2. EPFL, Lausanne, Switzerland. 3. University of Edinburgh, UK 4. University of Oslo, Norway. 5. KNMI, De Bilt, The Netherlands. 6. MPI-Met, Hamburg, Germany. 7. LLNL, Livermore, USA.
8. NASA-GISS, New York, USA. 9. MPI-Chem, Mainz, Germany. 10. RIVM, Bilthoven, The Netherlands 11. NOAA GFDL, Princeton, USA. 12. University of Virginia, USA. 13. Observatoire Midi-Pyrénées, France.
14. Indian Institute of Chemical Technology, Hyderabad, India. 15. NCAR, Boulder, USA. 16. Università L'Aquila, Italy. 17. IASB, Brussels, Belgium. 18. GEST, Washington, DC, USA. 19. Met Office, UK.
20. University of Cambridge, UK. 21. LSCE, Gif-sur-Yvette, France. 22. FRSGC JAMSTEC, Yokohama, Japan.
ACCENT intercomparison (Expt. 2)
• Focus on 2030 – of direct interest to policymakers• Go beyond radiative forcing: also consider ozone AQ, N-
and S-deposition, and the use of satellite data to evaluate models
• Present-day base case for evaluation:– S1: 2000
• Consider three 2030 emissions scenarios:– S2: 2030 IIASA CLE (‘likely’)– S3: 2030 IIASA MFR (‘optimistic’)– S4: 2030 SRES A2 (‘pessimistic’)
• Also consider the effect of climate change:– S5: 2030 CLE + imposed 2030 climate
Future changes in composition related to emissions1 year runsFuture changes in composition related to climate change5-10 year runs
Global NOx emission scenarios
0.0
40.0
80.0
120.0
160.0
200.0
1990 2000 2010 2020 2030
Europe North AmericaAsia + Oceania Latin America
Africa + Middle East Maximum Feasible Reduction (MFR)
SRES A2 - World Total SRES B2 - World Total
Figure 1. Projected development of IIASA anthropogenic NOx emissions by SRES world region (Tg NO2 yr-1).
CLE
SRES A2
MFR
2000 2030
Other emissions categories
• EDGAR3.2 ship emissions, and assumed 1.5%/yr growth in all scenarios
• Biomass burning emissions from van der Werf et al. (2003) – assumed these remained fixed to 2030 in all scenarios
• Aircraft emissions from IPCC(1999)• Modellers used their own natural emissions
• Specified fixed global CH4 for each case (from earlier transient runs)
Requested model diagnostics
• Monthly mean, full 3-D – O3, NO, NO2, CO, OH, …
– O3 budget terms
– CH4 + OH
– NOy, NHx and SOx deposition fluxes
– T, Q, etc. for climate change runs
• Daily NO2 column (GOME comparison)
• Hourly surface O3 (for AQ analysis)
• NETCDF files submitted to central database
26 Participating Models• CHASER_CTM• CHASER_GCM• FRSGC/UCI• GEOS-CHEM• GISS• GMI/CCM3• GMI/DAO• GMI/GISS• IASB• LLNL-IMPACT• LMDz/INCA-CTM• LMDz/INCA-GCM• MATCH-MPIC/ECMWF
• MATCH-MPIC/NCEP • MOZ2-GFDL• MOZART4• MOZECH• MOZECH2• p-TOMCAT• STOCHEM-HadAM3• STOCHEM-HadGEM• TM4• TM5• UIO_CTM2• ULAQ• UM_CAM
CTMs driven by analyses
CTMs driven by GCM outputCTMs coupled to GCMs
Mean model NOy wet dep (obs. overlain circles)
Mean model v Obs. HNO3 Wet dep.
EUROPE N. AMERICA
E. ASIAAFRICA
Taylor plots, HNO3 wet dep
Mean model NHx wet dep (obs. overlain circles)
Mean model v Obs. NH4 Wet dep.
EUROPE N. AMERICA
E. ASIAAFRICA
Taylor plots, NH4 wet dep
Different model resolutions
1°x1° 3°x3°
5°x5°Meanmodel
0.0000
0.1000
0.2000
0.3000
0.4000
0.5000
0.6000
0.7000
0.8000
Ratio of wet to total NOy deposition
S1
S2
S3
S4
S5
0
0.1
0.2
0.30.4
0.5
0.60.7
0.8
0.91
Ratio of HNO3/NO3 to NOy deposition
S1
S2
S3
S4
S5
Ratio wet to total deposition
00.10.20.30.40.50.60.70.8
GE
OS
-CH
EM
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AR
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OC
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D
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4
TM
5
ST
OC
HE
M_H
adGE
M
GF
DL
S1
S2
S4
S5
Ratio wet:total NHx deposition
Changes in NOy dep 2000-2030,
under 3 scenarios
IIASA CLE
IIASA MFR
SRES A2
Changes in NHx dep 2000-2030,
under 2 scenarios
IIASA CLE
SRES A2
NO Em ission and NOy deposition per region
0
200
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1400
1600
1800
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PE
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DLE
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JAP
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NLA
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OC
EA
N
mg
N/m
2/ye
ar
Emission
Deposition
Annual NO emission & NOy deposition (per unit area) by region(mean model)
NH3 Em iss ion and NHxdeposition per region
0
200
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1000
1200
1400
1600
1800
CA
NA
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A
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EE
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AN
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OC
EA
N
mg
N/m
2/y
ea
r
Emission
Deposition
Annual NH3 emission & NHx deposition (per unit area) by region(mean model)
Fractional NOy deposition
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
CA
NA
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NH
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rld
Nat. Vegetation
Agriculture/urban
Soil/desert
Water/ice
Fraction of NOy deposition to natural vegetation, agriculture/urban, soil/desert, and water/ice
Fractional NHx deposition
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
CA
NA
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A
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PA
N
OC
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N
NH
SH
Wo
rld
Nat. Vegetation
Agriculture/urban
Soil/desert
Water/ice
Fraction of NHx deposition to natural vegetation, agriculture/urban, soil/desert, and water/ice
% of natural vegetation with Nr dep > 1 g N/m2/yr
Fraction Nr deposition in excess of 1 g/m2/yearon natural ecosystems
0
10
20
30
40
50
60
70
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100
CA
NA
DA
US
A
CE
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L A
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RIC
A
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ME
RIC
A
NO
RT
HE
RN
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RIC
A
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FR
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%
S1
S2
S3
S4