Atmospheric Mercury Model Intercomparisons Presentation at Collaborative Meeting on Modeling Mercury in Freshwater Environments Niagara Falls, NY, January

Atmospheric Mercury Model Intercomparisons

Presentation atCollaborative Meeting on Modeling Mercury

in Freshwater Environments Niagara Falls, NY, January 19-20, 2006

Dr. Mark CohenNOAA Air Resources Laboratory

1315 East West Highway, R/ARL, Room 3316

Silver Spring, Maryland, [email protected]

http://www.arl.noaa.gov/ss/transport/cohen.html

2. Local Deposition Comparison:HYSPLIT-Hg vs.ISC (Gaussian Plume)


3. Comparison of Utility Contributions to the Great Lakes:HYSPLIT-Hg vs. CMAQ-Hg

4. Summary

2

1. EMEP Mercury Model Intercomparison




4. Summary

3


EMEP Intercomparison Study of Numerical Models for Long-Range Atmospheric Transport of Mercury

Intro-duction

Stage I Stage II Stage III Conclu-sionsChemistry Hg0 Hg(p) RGM Wet Dep Dry Dep Budgets

4

ParticipantsD. Syrakov …………………………….. Bulgaria….NIMH

A. Dastoor, D. Davignon ……………… Canada...... MSC-Can

J. Christensen …………………………. Denmark…NERI

G. Petersen, R. Ebinghaus …………...... Germany…GKSS

J. Pacyna ………………………………. Norway…..NILU

J. Munthe, I. Wängberg ……………….. Sweden….. IVL

R. Bullock ………………………………USA………EPA

M. Cohen, R. Artz, R. Draxler …………USA………NOAA

C. Seigneur, K. Lohman ………………..USA……... AER/EPRI

A. Ryaboshapko, I. Ilyin, O.Travnikov… EMEP……MSC-E


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5

Intercomparison Conducted in 3 Stages

I. Comparison of chemical schemes for a cloud environment

II. Air Concentrations in Short Term Episodes

III. Long-Term Deposition and Source-Receptor Budgets


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6

Model Acronym Model Name and Institution Stage

I II III

CAM Chemistry of Atmos. Mercury model, Environmental Institute, Sweden

MCM Mercury Chemistry Model, Atmos. & Environmental Research, USA

CMAQ Community Multi-Scale Air Quality model, US EPA

ADOM Acid Deposition and Oxidants Model, GKSS Research Center, Germany

MSCE-HM MSC-E heavy metal regional model, EMEP MSC-E

GRAHM Global/Regional Atmospheric Heavy Metal model, Environment Canada

EMAP Eulerian Model for Air Pollution, Bulgarian Meteo-service

DEHM Danish Eulerian Hemispheric Model, National Environmental Institute

HYSPLIT Hybrid Single Particle Lagrangian Integrated Trajectory model, US NOAA

MSCE-HM-Hem MSC-E heavy metal hemispheric model, EMEP MSC-E

Participating Models


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8

Hg(II), Reactive Gaseous Mercury [RGM]

Elemental Mercury [Hg(0)]

Particulate Mercury [Hg(p)]

Atmospheric Mercury

Re-emission of previously

deposited mercury

PrimaryAnthropogenic

Emissions

Naturalemissions Wet and Dry Deposition

CLOUD DROPLET

cloud

Hg(II) reduced to Hg(0) by SO2 and sunlight

Hg(0) oxidized to dissolved Hg(II) species by O3, OH,

HOCl, OCl-

Adsorption/desorptionof Hg(II) to/from soot

Hg(p)

Vapor phase Hg(0) oxidized to RGM and Hg(p) by O3,

H202, Cl2, OH, HCl Hg(p) Dissolution?


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9

Variation of Hg concentrations (ng/L)

0

20

40

60

80

100

120

140

160

TCM AER CAM MSC-E CMAQ

Models

Co

nce

ntr

atio

n, n

g/L


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10

Stage I Publications:

2001 Ryaboshapko, A., Ilyin, I., Bullock, R., Ebinghaus, R., Lohman, K., Munthe, J., Petersen, G., Seigneur, C., Wangberg, I. Intercomparison Study of Numerical Models for Long Range Atmospheric Transport of Mercury. Stage I. Comparisons of Chemical Modules for Mercury Transformations in a Cloud/Fog Environment. Meteorological Synthesizing Centre – East, Moscow, Russia.

2002 Ryaboshapko, A., Bullock, R., Ebinghaus, R., Ilyin, I., Lohman, K., Munthe, J., Petersen, G., Seigneur, C., Wangberg, I. Comparison of Mercury Chemistry Models. Atmospheric Environment 36, 3881-3898.

11


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11






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12

Model CMAQ-Hg ADOM HYSPLIT EMAP GRAHM DEHM MSCE-Hg

Model type Eulerian Eulerian Lagrangian Eulerian Eulerian Eulerian Eulerian

Scale/Domain

regional/Central and

Northern Europe

regional/ Central Europe

regional/EMEP

regional/EMEP

global Hemisphericregional/EMEP

Source of meteorological data

ECMWF TOGA reanalysis (MM5)

HIRLAMNCEP/NCAR

(MM-5)

SDA,NCEP/NCAR

reanalysis

Canadian Meteorolo-gical Centre

NCEP / NCAR reanalysis

SDA,NCEP/NCAR

reanalysis

Model top height (km) 15 10 15 5 30 15 3.9

Horizontal resolution (km, unless noted differently)

36 x 36 55 x 5536 x 36,

108 x 10850 x 50 1o x 1o 50 x 50

150 x 15050 x 50

Hg(0) boundary condition (ng/m3)

1.7 1.5 1.5 1.5 No 1.5 1.6 - 1.7

RGM boundary condition (pg/m3)

17 2 5 10 none 0 0

TPM boundary condition (pg/m3)

17 20 10 10 none 0 20

Gas-phase oxidation agents

O3, H2O2, Cl2, OH· O3

O3, H2O2,

Cl2, HClO3, OH! O3 O3 O3 (f)

Liquid-phase oxidation agents

O3, OH!, HOCl, OCl- O3

O3, OH!, HOCl,

OCl-O3 O3 O3 O3

Liquid-phase reduction agents

SO3=, hv, HO2 SO3

= SO3=, HO2 SO3

= SO3= SO3

= SO3=, HO2


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13

Anthropogenic Mercury Emissions Inventoryand Monitoring Sites for Phase II

(note: only showing largest emitting grid cells)

Mace Head, Ireland grassland shore Rorvik, Sweden

forested shore

Aspvreten, Sweden forested shore

Zingst, Germanysandy shore

Neuglobsow, Germany forested area


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14

Neuglobsow

Zingst

AspvretenRorvik

Mace Head


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15

Total Gaseous Mercury at Neuglobsow: June 26 – July 6, 1995

26-Jun 28-Jun 30-Jun 02-Jul 04-Jul 06-Jul 08-Jul0.0

1.0

2.0

3.0

4.0

Tot

al G

aseo

us M

ercu

ry (

ng/m

3)

MEASURED

NW

NW

NW

N

N

S

SE

NW

Neuglobsow


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16

Total Gaseous Mercury (ng/m3) at Neuglobsow: June 26 – July 6, 1995

26-Jun 28-Jun 30-Jun 02-Jul 04-Jul 06-Jul0

1

2

3

4 MEASURED


1

2

3

4 MSCE


1

2

3

4 CMAQ


1

2

3

4 GRAHM


1

2

3

4 EMAP


1

2

3

4 DEHM


1

2

3

4 ADOM


1

2

3

4 HYSPLIT


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17

Total Gaseous Mercury (ng/m3) at Neuglobsow: June 26 – July 6, 1995


1

2

3

4 MEASURED


1

2

3

4 MSCE

Using default emissions inventory

The emissions inventory is a critical input to the models…


1

2

3

4 MSCE - UBA

Using alternative emissions inventory


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18

Total Particulate Mercury (pg/m3) at Neuglobsow, Nov 1-14, 1999

02-Nov 04-Nov 06-Nov 08-Nov 10-Nov 12-Nov 14-Nov 16-Nov0

50

100

150MEASURED


50

100

150CMAQ


50

100

150GRAHM


50

100

150EMAP


50

100

150DEHM


50

100

150ADOM


50

100

150HYSPLIT


50

100

150MSCE

19

MSCE Neuglobsow RGM

0

10

20

30

40

50

60

11

/1/1

99

9

11

/2/1

99

9

11

/3/1

99

9

11

/4/1

99

9

11

/5/1

99

9

11

/6/1

99

9

11

/7/1

99

9

11

/8/1

99

9

11

/9/1

99

9

11

/10

/19

99

11

/11

/19

99

11

/12

/19

99

11

/13

/19

99

11

/14

/19

99

pg

/m3

ObsCalc

a

CMAQ Neuglobsow RGM

0

10

20

30

40

50

60

70

1/1

1/9

9

2/1

1/9

9

3/1

1/9

9

4/1

1/9

9

5/1

1/9

9

6/1

1/9

9

7/1

1/9

9

8/1

1/9

9

9/1

1/9

9

10

/11

/99

11

/11

/99

12

/11

/99

13

/11

/99

14

/11

/99

pg

/m3

ObsCalc

a

ADOM Neuglobsow RGM

0

10

20

30

40

50

60

70

11

/1/9

9

11

/2/9

9

11

/3/9

9

11

/4/9

9

11

/5/9

9

11

/6/9

9

11

/7/9

9

11

/8/9

9

11

/9/9

9

11

/10/

99

11

/11/

99

11

/12/

99

11

/13/

99

11

/14/

99

pg

/m3

ObsCalc

a

EMAP Neuglobsow RGM

0

5

10

15

20

25

11

/1/1

99

9

11

/2/1

99

9

11

/3/1

99

9

11

/4/1

99

9

11

/5/1

99

9

11

/6/1

99

9

11

/7/1

99

9

11

/8/1

99

9

11

/9/1

99

9

11

/10

/19

99

11

/11

/19

99

11

/12

/19

99

11

/13

/19

99

11

/14

/19

99

pg

/m3

ObsCalc

a

GRAHM Neuglobsow RGM

0

35

70

105

140

11/1

/99

11/2

/99

11/3

/99

11/4

/99

11/5

/99

11/6

/99

11/7

/99

11/8

/99

11/9

/99

11/1

0/99

11/1

1/99

11/1

2/99

11/1

3/99

11/1

4/99

pg/m

3

ObsCalc

a

HYSPLIT Neuglobsow RGM

0

10

20

30

40

50

60

11/1

/99

11/2

/99

11/3

/99

11/4

/99

11/5

/99

11/6

/99

11/7

/99

11/8

/99

11/9

/99

11/1

0/99

11/1

1/99

11/1

2/99

11/1

3/99

11/1

4/99

pg/m

3

ObsCalc

a


BudgetsDry DepWet DepRGMHg(p)Hg0Chemistry

Conclu-sions

Stage IIIStage IIStage IIntro-duction

DEHM Neuglobsow RGM

0

6

12

18

24

30

11/1

/199

9

11/2

/199

9

11/3

/199

9

11/4

/199

9

11/5

/199

9

11/6

/199

9

11/7

/199

9

11/8

/199

9

11/9

/199

9

11/1

0/19

99

11/1

1/19

99

11/1

2/19

99

11/1

3/19

99

11/1

4/19

99

pg/m

3

ObsCalc

a

Reactive Gaseous Mercury at Neuglobsow, Nov 1-14, 1999


BudgetsDry DepWet DepRGMHg(p)Hg0Chemistry

Conclu-sions

Stage IIIStage IIStage IIntro-duction

20

Overall Phase II statistics for 2-week episode means

0

20

40

60

80

100

Deviation fac tor

Perc

en

tag

e,

%

2 3 5 10

TGMTPM RGM

Deviation Factor

RGM: 90% within a factor of 10

RGM: 50% within a factor of 2

TPM: 90% within a factor of 2.5

TGM: all within a factor of 1.35


Intro-duction


21

Stage II Publications:

2003 Ryaboshapko, A., Artz, R., Bullock, R., Christensen, J., Cohen, M., Dastoor, A., Davignon, D., Draxler, R., Ebinghaus, R., Ilyin, I., Munthe, J., Petersen, G., Syrakov, D. Intercomparison Study of Numerical Models for Long Range Atmospheric Transport of Mercury. Stage II. Comparisons of Modeling Results with Observations Obtained During Short Term Measuring Campaigns. Meteorological Synthesizing Centre – East, Moscow, Russia.

2005 Ryaboshapko, A., Bullock, R., Christensen, J., Cohen, M., Dastoor, A., Ilyin, I., Petersen, G., Syrakov, D., Artz, R., Davignon, D., Draxler, R., and Munthe, J. Intercomparison Study of Atmospheric Mercury Models. Phase II. Comparison of Models with Short-Term Measurements. Submitted to Atmospheric Environment.

22


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22





23


Intro-duction


23

Phase III Sampling Locations


Intro-duction


24

Due to resource constraints, not all models simulated the entire year 1999…

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

CMAQ

HYSPLIT

ADOM

MSCE-HM

MSCE-HEM

DEHM

EMAP


Intro-duction


25

DE01 DE09 NL91 NO99 SE02 SE11 SE12 SE05 FI96

Monitoring Station

0.0

0.5

1.0

1.5

2.0

2.5

3.0

wet

Hg

depo

sitio

n (g

/km

2-m

ont

h)

Obs

MSCE-HM

MSCE-HM-Hem

HYSPLIT

DEHM

EMAP

CMAQ

August 1999 Mercury Wet Deposition


Intro-duction


26

F2 F3 F5 F10

Deviation Factor

0

20

40

60

80

100

Per

cent

of

resu

lts w

ithin

a g

iven

fac

tor

ADOM

CMAQ

EMAP

MSCE-HM

MSCE-HM-Hem

HYSPLIT

DEHM

Wet Deposition Summary

~60% within a factor of 2





Intro-duction


27

For dry deposition, there are no measurement results to compare the models against;

However, the models can be compared against each other…


Intro-duction


28


Monitoring Station

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Hg

dry

depo

sitio

n (g

/km

2-m

onth

)

model avg

MSCE-HM

MSCE-HEM

HYSPLIT

DEHM

EMAP

CMAQ

August 1999 Mercury Dry Deposition


Intro-duction


29

Main items of mercury atmospheric balance for the UK in 1999, t/yr


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30

Items of Hg atmospheric balances for the countries in 1999, t/yr[average modeled result (with ranges in parentheses)]

Item The UK Italy Poland

Total deposition 3.5 (3.1-4.2)

4.7(3.2-6.6)

11.8(9.6-13.1)

Dep. from own emissions

1.3 (0.8-1.6)

1.3 (0.6-1.9)

7.4(4.8-9.1)

Dep. from European emissions

0.3 (0.2-0.6)

0.8(0.5-1.3)

2.1(1.4-2.6)

Outflow 7.3 (7.0-7.8)

8.4 (7.9-9.2)

18.2 (16–21)


Intro-duction


31

Stage III Publication:

2005 Ryaboshapko, A., Artz, R., Bullock, R., Christensen, J., Cohen, M., Draxler, R., Ilyin, I., Munthe, J., Pacyna, J., Petersen, G., Syrakov, D., Travnikov, O. Intercomparison Study of Numerical Models for Long Range Atmospheric Transport of Mercury. Stage III. Comparison of Modelling Results with Long-Term Observations and Comparison of Calculated Items of Regional Balances. Meteorological Synthesizing Centre – East, Moscow, Russia.




4. Summary

32


0 - 15 15 - 30 30 - 60

distance range from source (km)

0.01

0.1

1

10

100

1000

for

1 kg

/day

sou

rce

ug/m

2-ye

ar

Hg(2)_50mHg(2)_250mHg(2)_500mHg(p)_250mHg(0)_250m

Wet + Dry Deposition: ISC (Kansas City)for emissions of different mercury forms from different stack heights

Calculated from data used to produce Appendix A of USEPA (2005): Clean Air Mercury Rule (CAMR) Technical Support Document: Methodology Used to Generate Deposition, Fish Tissue Methylmercury Concentrations, and Exposure for Determining Effectiveness of Utility Emissions Controls: Analysis of Mercury from Electricity Generating Units 33

0 - 15 15 - 30 30 - 60


0.01

0.1

1

10

100

1000

for

1 kg

/day

sou

rce

ug/m

2-ye

ar

Hg(2)_50m

Hg(2)_250m

Hg(2)_500m

Hg(p)_250m

Hg(0)_250m

Wet + Dry Deposition: HYSPLIT (Nebraska)for emissions of different mercury forms from different stack heights

0 - 15 15 - 30 30 - 60


0.01

0.1

1

10

100

1000

for

1 kg

/day

so

urce

ug/m

2-ye

ar

Hg(2)_50m

Hg(2)_250m

Hg(2)_500m

Hg(p)_250m

Hg(0)_250m

Wet + Dry Deposition: ISC (Kansas City)for emissions of different mercury forms from different stack heights

0 - 15 15 - 30 30 - 60


0.01

0.1

1

10

100

1000

for

1 kg

/day

so

urce

ug/m

2-ye

ar

Hg(2)_50m

Hg(2)_250m

Hg(2)_500m

Hg(p)_250m

Hg(0)_250m

Wet + Dry Deposition: ISC (Tampa)for emissions of different mercury forms from different stack heights

0 - 15 15 - 30 30 - 60


0.01

0.1

1

10

100

1000

for

1 kg

/day

so

urce

ug/m

2-ye

ar

Hg(2)_50m

Hg(2)_250m

Hg(2)_500m

Hg(p)_250m

Hg(0)_250m

Wet + Dry Deposition: ISC (Phoenix)for emissions of different mercury forms from different stack heights

0 - 15 15 - 30 30 - 60


0.01

0.1

1

10

100

1000fo

r 1

kg/d

ay s

our

ceug

/m2-

year

Hg(2)_50m

Hg(2)_250m

Hg(2)_500m

Hg(p)_250m

Hg(0)_250m

Wet + Dry Deposition: ISC (Indianapolis)for emissions of different mercury forms from different stack heights

HYSPLIT 1996

ISC: 1990-1994

Different Time Periods and Locations, but Similar Results

34




4. Summary

35


HYSPLIT-Hg results for Lake Erie (1999)

municipal waste incin --medical waste incin --

hazardous waste incin --industrial waste incin --

other waste incin --

chloralkali --other chemical manuf --

pulp/paper --cement/concrete --

mining --metallurgical processes --lamp manuf & breakage --other manufacturing --

other --

other fuel combustion --natural gas combustion --

mobile sources --oil combustion (non-mobile) --coal combustion (comm/ind) --

coal-fired elec gen not IPM --

coal-fired elec gen IPM --

0 1 2 3 4 5 6

Total Atmos. Dep Flux to Lake Erie (g Hg/km2-year)

USACanada

37

HYSPLIT-Hg results for Lake Erie (1999)

Modeled Mercury Deposition in the Great Lakes Region from all sources during 2001

Modeled Mercury Deposition in the Great Lakes Region attributable to U.S. coal-fired power plants during 2001

CMAQ-Hg results from EPA analysis performed for the Clean Air Mercury Rule

Erie Ontario Michigan Huron Superior0

1

2

3

4

5

6

7

8

De

po

sitio

n (

ug

/m2

-ye

ar) HYSPLIT

CMAQ

Model-estimated U.S. utility atmospheric mercury deposition contribution to the Great Lakes: HYSPLIT-Hg (1996 meteorology, 1999 emissions) vs. CMAQ-HG (2001 meteorology, 2001 emissions).

39

Erie Ontario Michigan Huron Superior0

1

2

3

4

5

6

7

8

De

po

sitio

n (

ug

/m2

-ye

ar)

HYSPLIT

25% added to CMAQ

CMAQ

Model-estimated U.S. utility atmospheric mercury deposition contribution to the Great Lakes: HYSPLIT-Hg (1996 meteorology, 1999 emissions) vs. CMAQ-Hg (2001 meteorology, 2001 emissions).

This figure also shows an added component of the CMAQ-Hg estimates -- corresponding to 30% of the CMAQ-Hg results – in an attempt to adjust the CMAQ-Hg results to account for the deposition underprediction found in the CMAQ-Hg model evaluation.

40




4. Summary

41


Summary of Model Intercomparisons

Extremely useful for improving models

Opportunity to work together and pool resources (e.g., everyone doesn’t have to create their own inventory or assemble monitoring data for evaluation)

Funding is a problem… most studies do not fund the individual participants….

10% of the work is doing the initial modeling analysis;

90% of the work is trying to figure out why the models are different – but we rarely have the resources to do much of this

Thanks!

Extra Slides


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45

Effect of Different Assumptions Regarding Hg(p) SolubilityAER/EPRI 0%; MSCE-EMEP 50%; CMAQ-EPA 100%

2000 European anthropogenic Hg emissions

240 t/yr


Intro-duction


European anthropogenic Hg re-emissions

50 t/yr

European natural Hg emissions

180 t/yr


Intro-duction


global natural Hg emissions1800 t/yr

1995 global anthropogenic Hg emissions1900 t/yr


Intro-duction


48

There are uncertainties in measurements -- even of precipitation amount…

NL91 De Zilk

020406080

100120140160


Months

Pre

cipi

tatio

n am

ount

, m

m

HM sampler

Hg sampler

FI96 Pallas

0

20

40

60

80

100

120


Months

Pre

cipi

tatio

n am

ount

, m

m

HM sampler

Hg sampler


Intro-duction



Monitoring Station

0.0

0.5

1.0

1.5

wet

Hg

depo

sitio

n (g

/km

2-m

ont

h)

Obs

MSCE-HM

MSCE-HM-Hem

HYSPLIT

DEHM

EMAP

ADOM

CMAQ

February 1999 Mercury Wet Deposition

49


Intro-duction


50


Monitoring Station

0.0

5.0

10.0

15.0

20.0

wet

Hg

depo

sitio

n (g

/km

2-y

ear)

Obs

MSCE-HM

MSCE-HM-Hem

DEHM

EMAP

Full Year 1999 Mercury Wet Deposition


Intro-duction


51


Monitoring Station

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Hg

dry

depo

sitio

n (g

/km

2-m

onth

)

model avg

MSCE-HM

MSCE-HEM

HYSPLIT

DEHM

EMAP

ADOM

CMAQ

February 1999 Mercury Dry Deposition


Intro-duction


52


Monitoring Station

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

Hg

dry

depo

sitio

n (g

/km

2-ye

ar)

model avg

MSCE-HM

MSCE-HEM

DEHM

EMAP

Full Year 1999 Mercury Dry Deposition


Intro-duction


53

In the following, the total model-predicted deposition (= wet + dry) is compared


Intro-duction


54

February 1999

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

NL91 DE09 DE01 SE11 SE02 NO99 SE12 SE05 FI96

Stations from south to north

Tot

al H

g de

posi

tion,

g/km

2/y

ADOM

EMAP

MSCE-HM

MSCE_HM_Hem

HYSPLIT

DEHM

CMAQ

Total Modeled Hg Deposition (wet + dry)


Intro-duction


55


August 1999

0

0.5

1

1.5

2

2.5

3

3.5



Tot

al H

g de

posi

tion,

g/km

2/y

ADOM

EMAP

MSCE-HM

MSCE-HM-Hem

HYSPLIT

DEHM

CMAQ

Note: ADOM was not run for August, so for this graph, ADOM results for July were used


Intro-duction


56


1999 as whole

0

5

10

15

20



Tot

al H

g de

posi

tion,

g/km

2/y

EMAP

MSCE-HM

MSCE-HM-Hem

DEHM


Intro-duction


57

Range

Deposition over polluted area in Feb

1999, g/km2

Total deposition over the countries in Feb 1999, kg

Wet Dry The UK Italy Poland

Minimum 0.24 0.10 76 143 300

MSCE-HM 0.54 0.16 235 261 1070

MSCE-HM-Hem

0.65 0.19 170 164 730

Maximum 1.03 0.39 240 334 1190

EMEP model results in relation to the other models


Intro-duction


58

Conclusions: Uncertainties in Mercury Modeling

• Elemental Hg in air - factor of 1.2

• Particulate Hg in air - factor of 1.5

• Oxidized gaseous Hg in air - factor of 5

• Total Hg in precipitation - factor of 1.5

• Wet deposition - factor of 2.0

• Dry deposition - factor of 2.5

• Balances for countries - factor of 2

Documents

Atmospheric Mercury Model Intercomparisons Presentation at Collaborative Meeting on Modeling Mercury in Freshwater Environments Niagara Falls, NY, January