12 th ICMGP, Jeju, Korea, 2015 Multi-model assessment of mercury cycling in the atmosphere Oleg Travnikov, Johannes Bieser, Ashu Dastoor, Carey Friedman,

12th ICMGP, Jeju, Korea, 2015

Multi-model assessment of mercury cycling in the atmosphere

Oleg Travnikov, Johannes Bieser, Ashu Dastoor, Carey Friedman, Ian Hedgecock, Volker Matthias, Andrew Ryzhkov, Noelle Selin,

Francesco De Simone, Shaojie Song, Xin Yang

Environment Canada


GMOS Mercury Modelling Task Force

Hg processes in the atmosphere

Global Mercury Observation System (GMOS)

Objectives:

• Multi-model study of Hg emissions and atmospheric processes

• Assessment of Hg intercontinental transport and future scenarios

• Evaluation of model performance using GMOS measurement data Aircraft measurements

RV Urania

Marine cruisesGround-based sites

Hg measurements within GMOS


Base run

• Simulation with the state-of-the-art model configuration (BASE)

MMTF model experiments

Emission effects

• Model run with no anthropogenic emissions (NOANT)

• Modified speciation of Hg anthropogenic emissions (ANTSPEC)

• Unified natural/secondary emissions (COMNAT)

• Improved emissions base on inverse modelling (INVEMI)Atmospheric chemistry

• Model run with no atmospheric chemistry (NOCHEM)

• Simulation with Br oxidation chemistry with two different sets of Br air concentration (BRCHEM1 and BRCHEM2)

• Simulation with OH - initiated oxidation chemistry (OHCHEM)

• Simulation with O3 - initiated oxidation chemistry

(O3CHEM)


MMTF model experimentsSource region apportionment

• Evaluation of Hg dispersion from 14 major source regions (Europe, North America, East Asia, South Asia etc.)

Emission sectors apportionment

• Evaluation of Hg dispersion from 3 groups of emission sectors (stationary combustion, industrial sources, intentional use)

Study setup

Anthropogenic emissions: AMAP/UNEP inventory for 2010

Natural/legacy emissions: Model specific

Target year: 2013


Participating chemical transport models (CTM):

Model Scale Institution

GLEMOS global/regional EMEP/MSC-E

ECHMERIT global CNR-IIA (Italy)

GEM-MACH-Hg

global Environment Canada

GEOS-Chem global MIT (USA)

CMAQ-Hg regional HZG (Germany)

WRF-Chem regional CNR-IIA (Italy)

p-TOMCAT global Cambridge (UK)



Participating chemical transport models (CTM):

Model Scale Institution

GLEMOS global/regional EMEP/MSC-E

ECHMERIT global CNR-IIA (Italy)

GEM-MACH-Hg

global Environment Canada

GEOS-Chem global MIT (USA)

CMAQ-Hg regional HZG (Germany)

WRF-Chem regional CNR-IIA (Italy)

p-TOMCAT global Cambridge (UK)



Location of monitoring sites

Measurement data

Monitoring networks:

• Global GMOS network for Hg

• Regional Hg networks (EMEP, NADP/MDN)

• Regional Hg networks (AMNet, NAtChem)

GMOS partners:

Measurement data used for the analysis (2013)

GEM/TGM in air (28 sites)

Wet deposition (135 sites)

GEM, GOM, PBM in air (11 sites)


Model experiments: BASE run

GLEMOS GEOS-Chem

GEM-MACH-Hg ECHMERIT

Hg0 air concentration (2013)

0.6 1 2 30.6

1

2

3

Mod

el, n

g/m

3

Observed, ng/m3

0.6 1 2 30.6

1

2

3

Mod

el, n

g/m

3

Observed, ng/m3

0.6 1 2 30.6

1

2

3

Mod

el, n

g/m

3

Observed, ng/m3

0.6 1 2 30.6

1

2

3

Mod

el, n

g/m

3

Observed, ng/m3


GLEMOS GEOS-Chem


Model experiments: BASE runHg wet deposition (2013)

2 10 1002

10

100

Mod

el, n

g/m

2 /day

Observed, ng/m2/day

2 10 1002

10

100

Mod

el, n

g/m

2 /day

Observed, ng/m2/day

2 10 1002

10

100

Mod

el, n

g/m

2 /day

Observed, ng/m2/day

2 10 1002

10

100

Mod

el, n

g/m

2 /day

Observed, ng/m2/day


Inter-hemispheric gradient

GLEMOS GEOS-Chem


Zonal-mean distribution of Hg0 concentration

0.5

1.0

1.5

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d G

EM

0.5

1.0

1.5

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d G

EM

0.5

1.0

1.5

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d G

EM

0.5

1.0

1.5

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d G

EM

BASE run No chemistryNo anthrop. emissionMeasurements

The inter-hemispheric gradient of Hg concentration is largely

defined by atmospheric chemistry and natural/legacy

emissions



Hg + Br (1) Hg + O3Hg + OHMeasurements

0.5

1.0

1.5

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d G

EM

0.5

1.0

1.5

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d G

EM

0.5

1.0

1.5

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d G

EM

0.5

1.0

1.5

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d G

EM

Hg + Br (2)

GLEMOS GEOS-Chem


Zonal-mean distribution of Hg0 concentration

1

10

100

1000

-90 -60 -30 0 30 60 90Latitude

Br

con

cent

ratio

n, p

pq Br concentration

GEOS-Chem

p-TOMCAT

Both Br and OH chemistry allows reproducing inter-

hemispheric gradient. Available data on Br air concentration is

highly uncertain



0

1

2

3

4

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d w

et

de

posi

tion

0

1

2

3

4

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d w

et

de

posi

tion

0

1

2

3

4

-90 -60 -30 0 30 60 90Latitude

Nor

ma

lize

d w

et

de

posi

tion

GLEMOS GEOS-Chem

GEM-MACH-Hg

Zonal-mean distribution of Hg wet deposition

Hg + Br (1) Hg + O3Hg + OHMeasurements

Precipitation

Br and OH/O3 mechanisms produce significantly different

distributions of wet deposition in ITCZ and Southern

Hemisphere. More measurements are needed in these regions


Seasonal variationMean seasonal variation of Hg wet deposition (Europe)

0.0

0.5

1.0

1.5

2.0

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

Nor

ma

lize

d w

et

de

posi

tion

0.0

0.5

1.0

1.5

2.0


Nor

ma

lize

d w

et

de

posi

tion

0.0

0.5

1.0

1.5

2.0


Nor

ma

lize

d w

et

de

posi

tion

GLEMOS GEOS-Chem

GEM-MACH-Hg

BASE run No chemistryNo anthrop. emissionMeasurements

Seasonal variation of Hg wet deposition in Europe is mostly

defined by oxidation chemistry


0.0

0.5

1.0

1.5

2.0


Nor

ma

lize

d w

et

de

posi

tion

Seasonal variation

0.0

0.5

1.0

1.5

2.0


Nor

ma

lize

d w

et

de

posi

tion

0.0

0.5

1.0

1.5

2.0


Nor

ma

lize

d w

et

de

posi

tion

GLEMOS GEOS-Chem

GEM-MACH-Hg

Hg + Br (1) Hg + O3Hg + OHMeasurements Hg + Br (2)

Mean seasonal variation of Hg wet deposition (Europe)

OH-initiated chemistry better reproduces seasonal cycle of wet

deposition in Europe


Source apportionment

Source/receptor regions

Europe AfricaMiddle East

North AmericaCentral AmericaSouth America

South AsiaEast AsiaSoutheast AsiaAustralia and NZ

CIS countries

Antarctica

Arctic

Europe

Australia and NZ

Africa

Arctic

South America

South Asia

Middle East

North America

East Asia

Source apportionment of Hg anthropogenic deposition


Update of modelling results in GMA 2013

Available online: http://www.amap.no/documents/doc/global-mercury-modelling-update-of-modelling-results-in-the-global-mercury-assessment-2013/1218

Published by UNEP & AMAP

Contents:

• Global patterns of mercury air concentration and deposition

• Estimates of mercury intercontinental transport

• Mercury deposition from different emission sectors


Preliminary conclusions

• The inter-hemispheric gradient of Hg0 concentration is largely defined by atmospheric chemistry and natural/legacy emissions

• Both Br and OH chemistry allows reproducing inter-hemispheric gradient of Hg0. However, available data on Br air concentration is highly uncertain

• Br and OH/O3 mechanisms produce significantly different

distributions of wet deposition in ITCZ and Southern Hemisphere. More measurements are needed in these regions

• Seasonal variation of Hg wet deposition in Europe is mostly defined by oxidation chemistry

• OH-initiated chemistry better reproduces seasonal cycle of wet deposition in Europe


Further plans

• Involve speciated Hg measurements to evaluate GOM and PBM concentrations

• Use highly temporally resolved (hourly) data to analyze diurnal variation of GEM, GOM and PBM concentration

• Utilize the CARIBIC data to evaluate TGM distribution in upper troposphere

• Provide open access to the MMTF model simulations data through the GMOS Spatial Data Infostructure

Documents

12 th ICMGP, Jeju, Korea, 2015 Multi-model assessment of mercury cycling in the atmosphere Oleg Travnikov, Johannes Bieser, Ashu Dastoor, Carey Friedman,