analysis of atmospheric mercury speciation at hedo station, okinawa
DESCRIPTION
Analysis of Atmospheric Mercury Speciation at HEDO Station, Okinawa. Beijing. Shanghai. Hong Kong. Anthropogenic Sources of Hg in 1995 Pacyna et al.- 2003 LRT Workshop. Hg 0 – Ton/yr. Hg(II) – Ton/yr. PHg – Ton/yr. Atmospheric Mercury Nomenclature. - PowerPoint PPT PresentationTRANSCRIPT
Eric Prestbo Ph.D. ([email protected])
Analysis of Atmospheric Mercury Speciation at HEDO Station, Okinawa
Eric Prestbo Ph.D. ([email protected])
Eric Prestbo Ph.D. ([email protected])
Anthropogenic Sources of Hg in 1995Pacyna et al.- 2003 LRT Workshop
Hg0 – Ton/yr
Hg(II) – Ton/yr
PHg – Ton/yr
Eric Prestbo Ph.D. ([email protected])
Atmospheric Mercury Nomenclature
• Hg0 or GEM - Gaseous Elemental Mercury
• PHg – Particulate Bound Hg (2.5 um)
• RGM - Reactive Gaseous Mercury - HgCl2?
Eric Prestbo Ph.D. ([email protected])
Instrument Description: Atmospheric Mercury Speciation
Eric Prestbo Ph.D. ([email protected])
HEDO Mercury
0
1
2
3
4
5
84 88 92 96 100 104 108 112 116 120
Julian Day
Ele
me
nta
l Hg
(n
g/m
3)
0
10
20
30
40
50
PH
g a
nd
RG
M (
pg
/m3
)
Hg0 PHg RGM
Eric Prestbo Ph.D. ([email protected])
Measurement vs Model
Hedo Mean Hg0 = 2.04 ng/m3
Hedo Max Hg0 = 5.47 ng/m3
Seignuer et al., 2004 ES&T 38:555
Eric Prestbo Ph.D. ([email protected])
Measurement vs Model
Dastoor and Larocque., 2004 Atmos. Env. 38:147
Hedo Mean Hg0 = 2.04 ng/m3
Hedo Max Hg0 = 5.47 ng/m3
Eric Prestbo Ph.D. ([email protected])
Measurement vs ModelHedo RGM Mean = 4.51 pg/m3
Hedo RGM Max = 32.5 pg/ m3
Seignuer et al., 2004 ES&T 38:555
Eric Prestbo Ph.D. ([email protected])
Measurement vs ModelHedo PHg Mean = 3.05 pg/m3
Hedo PHg Max = 16.5 pg/ m3
Seignuer et al., 2004 ES&T 38:555
Eric Prestbo Ph.D. ([email protected])
Comparison of Model and Observation of Hg0 Seignuer et al., 2004 ES&T 38:555
Location Date Model (ng/m3)
Obs
W. Korea Spring 2001
3.72 2.13
Seoul, Korea Sept-97 May-98
3.43-3.94 2.03; 2.12
Kyushu, Japan 1996 10.8 1.70
Beijing, China Jan, Feb, Sept 98
6.2 – 24.7 2.26; 2.38
HEDO, Okinawa Spr-2004 1.7-1.9 2.04
Changchun, China
**PHg**
Jul-Jan 2000
0.02-2 (PHg) 0.06 - 2
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Beijing - China
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
LOCAL?
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125
Julian Day
Hg
0 (
ng
/m3 )
and
1-u
m S
O4 (
ug
/m3 x
10)
0
100
200
300
400
500
600
CO
(p
pb
)
Hg0 CO
Eric Prestbo Ph.D. ([email protected])
High Hg0 and CO often begins with rainfall note also SO4 washout
HEDO Hg0, CO, 1-um SO4 and Rainfall
0
1
2
3
4
5
80 85 90 95 100 105 110 115 120 125Julian Day
Hg
0 (
ng
/m3)
an
d R
ain
(m
m)
0
100
200
300
400
500
CO
(p
pb
) an
d 1
-um
SO
4
x10
(ug
/m3 )
Hg0 Rain (mm) CO 1-um SO4
Eric Prestbo Ph.D. ([email protected])
Evidence for Biomass Signal?Organic Rich – Sulfate Low
0
1
2
3
4
5
6
89 90 91 92 93 94 95Julian Day
Hg
0 (n
g/m
3 ) a
nd
1-u
m O
rg (
ug
/m3 )
0
100
200
300
400
500
600
CO
(p
pb
) a
nd
1-u
m S
O4
(u
g/m
3 x
10
)
Hg0 1-um Organic CO 1-um SO4
Eric Prestbo Ph.D. ([email protected])
Evidence for Biomass Signal?Organic Rich – Sulfate Low
0
1
2
3
4
5
6
83 84 85 86 87 88 89Julian Day
Hg
0 (n
g/m
3) a
nd
1-u
m O
rg (
ug
/m3)
0
100
200
300
400
500
600
CO
(p
pb
) an
d 1
-um
SO
4 (u
g/m
3 x1
0)
Hg0 1-um Organic CO 1-um SO4
Eric Prestbo Ph.D. ([email protected])
No clear observation of a dust event
0
1
2
3
4
5
6
80 85 90 95 100 105 110 115 120 125Julian Day
Hg
0 (n
g/m
3 )
0
100
200
300
400
500
600
CO
(p
pb
), S
cat
(m-1
x 1
06)
an
d
SO
4 (u
g/m
3 x1
0)
Hg0 CO 1-um SO4 Neph
Eric Prestbo Ph.D. ([email protected])
PHg correlates well with SO4 and CO
0
5
10
15
20
25
30
85 89 93 97 101 105 109 113 117 121
Julian Day
PH
g (
pg
/m3
) a
nd
1-u
m S
04
(u
g/m
3)
0
100
200
300
400
500
600
CO
(pp
b)
1-um SO4 PHg CO
Eric Prestbo Ph.D. ([email protected])
RGM Does not correlate well with CO or SO4 - Why?
y = 1.4278x + 208.91R2 = 0.0133
0
100
200
300
400
500
600
700
800
0 5 10 15 20 25 30 35
RGM (pg/m3)
CO
(p
pb
)
Eric Prestbo Ph.D. ([email protected])
Low-Level RGM and PHg Emissions results
in faster local removal by Dry Deposition?
< 50 Meter Total Hg Emissions (tons/yr)
>150 Meter Total Hg Emissions (tons/yr)
Pacyna et al.- 2003 LRT Workshop
Eric Prestbo Ph.D. ([email protected])
Why are RGM values lower than models and uncorrelated with pollution
compounds?
Hypothesis – RGM from anthropogenic emissions are preferentially reduced to Hg0 via the complex chemistry of S02 > S03 > S04 during cloud droplet formation and evaporation
Eric Prestbo Ph.D. ([email protected])
What controls [RGM] – Photochemistry?
HEDO - Hg Species Diurnal Pattern
1.6
1.8
2.0
2.2
2.4
0:00
-2:0
0
3:00
-5:0
0
6:00
-8:0
0
9:00
-11:
00
12:0
0-14
:00
15:0
0-17
:00
18:0
0-20
:00
21:0
0-23
:00
Local Time of Day (JST)
Hg
0 (n
g/m
3)
1
3
5
7
9
RG
M a
nd
PH
g (
pg
/m3)
GEM
PHg
RGM
Eric Prestbo Ph.D. ([email protected])
RGM and Solar Insolation
0
10
20
30
40
103 104 105 106 107 108 109 110 111 112 113
Julian Date
[RG
M]
(pg
/m3 )
0
1000
2000
3000
4000
So
lar
Inso
lati
on
(w
atts
/m2 )
RGMSolar Flux
0
1
2
3
4
103 104 105 106 107 108 109 110 111 112 113Julian Day
Hg
0 (
ng
/m3)
0
100
200
300
400
CO
(p
pb
)
Hg0 CO
Hg0
Eric Prestbo Ph.D. ([email protected])
Future Data Interpretation
• More refined analysis of each event with respect to AMS and meteorology
• Support hypothesis that SO3 is preferentially converting emitted Hg(II) to Hg0 during cloud water processing (formation/evaporation)
• Rule out local impacts
Eric Prestbo Ph.D. ([email protected])
Future: Need Hg Deposition Data!
• Inventories coupled to models predict high deposition in NW Pacific due to RGM and PHg emissions
• Measurements needed to confirm at HEDO and elsewhere
• Should be event based – at least for intensive study periods
• What Hg deposition data is currently being collected or published?
Eric Prestbo Ph.D. ([email protected])
Continuous Mercury Speciation at HEDO
• Depending on support-level we can do complete Automated Hg speciation system – or only total gaseous Hg with select intensive studies