INTERCONTINENTAL TRANSPORT OF OZONE AND ITS SEASONAL VARIATIONS IN EUROPE
Dick Derwent
rdscientific
2nd ICAP Workshop
Chapel Hill, North Carolina
October 21st -22nd 2004
This work was sponsored by the United Kingdom Department for Environment, Food and Rural Affairs under contract CPEA 7.
STOCHEM
• three-dimensional global Lagrangian chemistry transport model
• fully coupled to Hadley Centre global atmosphere-ocean climate model• or run from operational analyses from Met Office NWP model
• full chemistry of methane, ozone, 10 emitted VOCs, NOx, acid rain and secondary aerosol formation from SO2, DMS, NH3
OZONE LABELLING TECHNIQUES
d/dt [O3] = k1[HO2][NO] + k2[RO2][NO] – losses
If air parcel is over North America then
d/dt[O3 America] = k1[HO2][NO] + k2[RO2][NO] – losses
Otherwise
d/dt[O3 America] = - losses
Origins of European Ozone
The origins of tropospheric background air across Europe
8 ppb
20 ppb
5 ppb
10 ppb
STOCHEM MODEL VS OBSERVATION FOR A RURAL LOCATION IN THE UNITED KINGDOM
0
10
20
30
40
50
60
1 2 3 4 5 6 7 8 9 10 11 12
Month of the Year
O3
, pp
b O3
Obs
Harwell, Oxfordshire 1998
INTERCONTINENTAL ATTRIBUTION OF THE OZONE AT A RURAL UNITED KINGDOM LOCATION
0
10
20
30
40
50
60
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
O3
, p
pb
Asia
America
Europe
Stratosphere
Harwell, Oxfordshire 1998
HOW CAN THESE MODEL PREDICTION OF INTERCONTINENTAL TRANSPORT BE VALIDATED ?
• Biomass burning during 1998
• Halocarbon transport to Mace Head, Ireland
Mace Head,
Ireland
1000s km uninterrupted fetch across North Atlantic Ocean
Long range transport brings polluted air from Europe
BASELINE CONCENTRATIONS OF CO AND H2 AT MACE HEAD, IRELAND
50
70
90
110
130
150
170
190
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
CO
CO
NC
(pp
b)
465
485
505
525
545
565
585
H2
CO
NC
(pp
b)
CO MONTHLY MEANS CO 12-MONTH AVERAGEH2 MONTHLY MEANS H2 12-MONTH AVERAGE
BASELINE CONCENTRATIONS OF CO2 AND CH4 AT MACE HEAD, IRELAND
1760
1780
1800
1820
1840
1860
1880
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
CH
4 C
ON
C (
PP
B)
345
355
365
375
385
395
CO
2 C
ON
C (
PP
M)
CH4 MONTHLY MEANS CH4 12-MONTH AVERAGECO2 MONTHLY MEANS CO2 12-MONTH AVERAGE
BASELINE CONCENTRATIONS OF OZONE AT MACE HEAD, IRELAND
15
20
25
30
35
40
45
50
55
Jan-
87
Jan-
88
Jan-
89
Jan-
90
Jan-
91
Jan-
92
Jan-
93
Jan-
94
Jan-
95
Jan-
96
Jan-
97
Jan-
98
Jan-
99
Jan-
00
Jan-
01
Jan-
02
Jan-
03
Jan-
04
OZ
ON
E C
ON
C (P
PB
)
Ozone Baseline monthly means 12-month moving average
MONTHLY MEAN BASELINE O3 CONCENTRATIONS EXPRESSED AS ANOMALIES FROM 1990-1999 MEANS
-2
-1
0
1
2
3
4
5
6
Jan-98
Mar-98
May-98
Jul-98
Sep-98
Nov-98
Jan-99
Mar-99
May-99
Jul-99
Sep-99
Nov-99
Ozo
ne
ano
mal
y ,
pp
b
Mace Head, Ireland, all hours
MONTHLY MEAN DAILY MAXIMUM O3 CONCENTRATIONS FOR THE 54 EMEP STATIONS EXPRESSED AS ANOMALIES FROM
THE 1990-1999 MEANS
Average anomaly from the 10-year mean for 54 surface EMEP sites during 1998 and 1999
-10
-8
-6
-4
-2
0
2
4
6
8
10
Ja
n-9
8
Ma
r-98
Ma
y-9
8
Ju
l-98
Se
p-9
8
No
v-9
8
Ja
n-9
9
Ma
r-99
Ma
y-9
9
Ju
l-99
Se
p-9
9
No
v-9
9
An
om
aly
oz
on
e ,
pp
b
MONTHLY MEAN DAILY MAXIMUM O3 CONCENTRATIONS FOR THE UK RURAL SITES EXPRESSED AS ANOMALIES FROM
THE 1990-1999 MEANS
-20
-15
-10
-5
0
5
10
15
Ja
n-9
8
Ma
r-98
Ma
y-9
8
Ju
l-98
Se
p-9
8
No
v-9
8
Ja
n-9
9
Ma
r-99
Ma
y-9
9
Ju
l-99
Se
p-9
9
No
v-9
9
Oz
on
e a
no
ma
ly ,
pp
b
Eskdalemuir
Lough Navar
Yarner Wood
High Muffles
Strath Vaich
Ashton Hill
Bottesford
Bush Estate
Glazebury
Harwell
Ladybower
Lullington Heath
Sibton
NO2-O3-Ox-NOx ANALYSES FOR BRIDGE PLACE, LONDON
0
10
20
30
40
50
60
0 20 40 60 80 100 120
[NOX] (ppb)
[NO
2],
[O3]
, [O
X]
(ppb
) Bridge Place London (1991-1999)
1999
Jenkin et al. (2004)
CH2Cl2 AT MACE HEAD, IRELAND DURING 1998
0
50
100
150
200
250
CH
2Cl2
, p
pt
January December
GC-MS observations from Prof Peter Simmonds
CH2Cl2 IN STOCHEM WITH INTERCONTINENTAL LABELLING
0
40
80
120
160
20001
/01/
98
01/0
2/98
01/0
3/98
01/0
4/98
01/0
5/98
01/0
6/98
01/0
7/98
01/0
8/98
01/0
9/98
01/1
0/98
01/1
1/98
01/1
2/98
CH
2Cl2
, p
pt Tot
EU
AM
AS
Peaks are European in origin
CH2Cl2 FLUCTUATIONS CLOSE TO THE BASELINE
0
40
01/0
1/98
01/0
2/98
01/0
3/98
01/0
4/98
01/0
5/98
01/0
6/98
01/0
7/98
01/0
8/98
01/0
9/98
01/1
0/98
01/1
1/98
01/1
2/98
CH
2Cl2
, p
pt Tot
EU
AM
AS
Transport from North America
LAGRANGIAN DISPERSION MODEL NAME
• employs same meteorological fields as STOCHEM• simulates transport and dispersion using upwards of a million air parcels• released at unit density in a model domain that stretches across the North Atlantic Ocean• plots show air concentration at Mace Head produced by unit density emissions at that point
GC-MS OBSERVATIONS OF CH2Cl2 DURING MARCH 1998
40
41
42
43
44
45
46
47
48
49
50
CH
2C
l2,
pp
t
Prof Peter Simmonds
Intercontinental transport from USA
HALOCARBONS AS TRACERS OF INTERCONTINENTAL TRANSPORT
• Short atmospheric lifetimes means that their baseline concentrations are low compared to current global annual emission rates• GC-MS has the sensitivity to observe them at ppt levels• current USA emission rates are significant for some halocarbons, particularly HFCs
INTERCONTINENTAL TRANSPORT OF OZONE ON 14-15 JULY 2004 FROM NEW YORK-BOSTON TO MACE HEAD
-4
-2
0
2
4
6
8
10
12
00:00:00 12:00:00 00:00:00 12:00:00 00:00:00
Co
nc
-0.5
0
0.5
1
1.5
2
2.5
HFC-134a
HCFC-22
O3 in ppb
HFC-152a
HCFC-124
HCFC-142b
HCFC-123
HCFC-141b
CH2Cl2
CCl2CCl2
14th July 15th July
CONCLUSIONS
• Modelling studies point to the importance of intercontinental transport in influencing the distribution of ozone in Europe
• This influence extends to its seasonal variations and trends with time
• The observations of reactive halocarbons are now available at Mace Head to study intercontinental transport on a systematic basis
• Aim is the validate the models of intercontinental transport across the North Atlantic Ocean