Air Quality trend analyses under EMEP/TFMM
and link to EEA work
Augustin COLETTE (INERIS), Chair of the TFMM/CLRTAP
TFMM National Experts, CCC, MSC-E, MSC-W, ETC/ACM
20th EIONET Air Quality Management and Assessment Workshop
Overview

TFMM Trend Assessment




Methodology
Measurement
Modelling (Eurodelta)
Link with EEA-ETC/ACM
trend work
Torseth et al., ACP, 2012
TFMM Trend Assessment 2014-2015







Spring 2014:TFMM Annual Meeting

Initial trend assessment studies

Discussion on methodologies

Agreement on methodology & modelling setup

Draft analyses & definition of writing teams

Drafts results + writing report

Review

Publications
Fall 2014:Trend Workshop
Winter 2014-2015
Spring 2015 : TFMM Annual Meeting
Fall 2015: EMEP Steering Body
Winter 2015-2016
Spring 2016 : TFMM Annual Meeting
Trend methodology for observations

Specifications



Time periods: 1990-2012 / 1990-2001 / 2002-2012
Data completeness: 75% of annual coverage and 75% of years covered
Statistical analysis:



Concentrations and wet deposition fluxes of Pb, Cd, Hg and B[a]P + other POPs: biexponential on the basis of monthly values;
Ozone (avg & max 8hr), NO2, PM10, PM2.5, SO2, sulphate, nitrate and carbonaceous
atmospheric concentration and sulfur and nitrogen precipitation chemistry: MannKendall and Sen-Theil slope on the basis of annual values & by season
Process


Centralised analysis (Centres) published on open TFMM wiki
Supplemented by national expert knowledge of

(i) data issues, (ii) need for filtering, (iii) non-linearity and changes of slopes in the
record, (iv) additional compounds, (v) add or discard sites, (vi) changes in seasonal
cycles, (vii) relation with local emission changes
Trend methodology for models: EURODELTA


6 regional CTMs + EMEP/MSC-W
Common setup




Meteorology
Emissions (GAINS/ECLIPSE)
Boundary conditions
ED3-Trends
3 tiers of experiments




1990/2000/2010 reference [7]
Sensitivity to emissions [6]
Sensitivity to boundary conditions [3]
Full 20yr hindcast [2]
EURODELTA-Trends

Key Questions
Model validation
How do model compare with observations in 1990, 2000, and 2010 ?
How do models capture the trend in observations ?
Can we conclude on the uncertainties in emissions?
European policy
effectiveness
What if no emission change occurred in Europe ?
Did “potency” changed over the past 20yrs?
Can we identify changes in SIA formation ?
Non-European influence
What if no emission changed beyond Europe ?
What is the uncertainty related to boundary conditions ?
Meteorological variability
Does meteorological variability contribute to the AQ trend over the past
20 yrs?
Impacts
Link with effect community (health & ecosystems)
What model dynamical evaluation means for IAM?
O3: Average trend

Composite of observations at
54 EMEP sites with valid
observations over 1990-2012

Annual means were increasing
in the 1990s

Ozone peaks decreased since
2000
O3: Statistics over the EMEP network

Relative Change (%)
1990-2000
2001-2012


Annual Mean
7.7
-5.3
JJA avg of daily Max
-6.9
-12.9
SOMO35
10.1
-32.5
Fraction of stations with significant trend (%, pval<0.05)
Substantial average changes, yet unsignificant trends

short time period & interannual variability
AOT40
-21.7
-42.0
EMEP&AIRBASE Complementarity

AIRBASE:


~230 RU background
stations 2002-2012
EMEP:

~50 RU background stations
1990-2012
EMEP / 1990-2001 (54)

EMEP / 2002-2012 (54)
AIRBASE / 2002-2012 (231)
Consistent conclusion on the O3 trends in 2000’s when expanding to
airbase coverage
O3: Lower photochemical production

Larger decreases at EMEP
sites where O3 levels where
higher
Courtesy D. Derwent

Negative trends for mean
O3 in summer, even at urban
sites
ETC/ACM - EEA
O3: EURODELTA : modelled exposure

6-RCTM median pop-weighted average SOMO35
2000
Relative Change
2010 vs 2000
2010
Std dev
Sulphur & Nitrogen Compounds

General decrease, some gaps between model&observations
Ox. Sulphur
>
Ox. Nitrogen
>
Red. Nitrogen
Particulate Matter

Average Trend at EMEP sites
2002-2012
Model
Observed
PM10
-2.6% / yr
2.4% / yr
PM2.5
-3.7 % / yr
3.0 % / yr
Solid line: Measurements
Dottet line: EMEP model

Confirmed at AIRBASE sites,
with slighly larger trends close
to the sources
ETC/ACM - EEA
PM2.5 Modelled Exposure (EURODELTA)


1990
Average population weighted exposure by country
6-model median ensemble in 1990 and 2010
2010
EURODELTA3
PM2.5 Modelled Exposure (EURODELTA)

Change in exposure between 1990 and 2010


Left: relative change in the EMEP model (%)
Right: std dev. of the relative change in the 6-model ensemble
EURODELTA3
BaP Trends: example of Germany
Air concentrations (modelling)
Emissions (official data)
160
3
Total reduction
Growth from 2005 to 2012
1.2
68%
22%
Emissions, t/y
1
0.8
0.6
0.4
0.2
Value
Total reduction
Growth from 2005 to 2012
140
120
80
60
40
Value
Trend
20
Trend
0
77%
31%
100
8
DE1
2012
2010
2008
2006
2004
2002
2000
DE9
ng/l
6
4
2
4
2
0
Total reduction
57%
Growth from 2005 to 2012 22%
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
0
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
ng/l
1998
8
Total reduction
56%
Growth from 2005 to 2012 29%
6
Trend analysis of
measurements at
German sites
1996
1994
1992
2012
2010
2008
2006
2004
2002
2000
1998
1996
1994
1992
1990
0
1990
Air concentrations, ng/m
1.4
Heavy Metal: total reduction (1990-2012)
Lead
Wet dep.
Air conc.
Mercury
Wet dep.
Air conc.
100
100
80
80
80
60
40
20
0
-20
60
40
20
0
-20
Total reduction, %
100
Total reduction, %
Total reduction, %
Air conc.
Cadmium
60
40
20
0
-20
Wet dep.
Heavy Metals Trends

HMs:

Relative increase of the importance
of non-EMEP and secondary sources
Conclusion

Main messages

O3:




PM & SIA


Larger decrease in the 1990s
Next steps




Larger decrease in the 1990s
HM & POPs


increase in baseline in the 1990s
decrease of the peaks in the 2000s
Relative small fraction of sites with significant trends
Full draft end of 2015
Publication Spring 2016
Ongoing Eurodelta analysis
Collaboration with other initiatives




EEA-ETC/ACM
CLRTAP AR
WGE Trend Report
TOAR