ETC HE Repo 2025/4
In e im ai quali y maps o EEA membe and
coope a ing coun ies o 2024
PM, O3, and NO2 spa ial es ima es
Au ho s:
Jan Ho álek (CHMI), Leona Vlasáko á (CHMI), Ma ké a Sch eibe o á (CHMI),
Philipp Schneide (NILU), Nina Benešo á (CHMI), Ondřej Vlček (CHMI)
ETC HE Repo 2024/X
Co e design: EEA
Co e image: Maps showing PM2.5 annual a e age ( op), O3 indica o peak season a e age o maximum daily 8-hou means
(bo om le ) and NO2 annual a e age (bo om igh ) o 2024. (This epo ´s Maps 2.3, 3.1 and 4.1.)
Layou : EEA / ETC HE (CHMI)
Publica ion Da e: 21 No embe 2025
DOI: 10.5281/zenodo.17601140
EEA ac i i y: Human heal h and he en i onmen
Legal no ice
P epa a ion o his epo has been co- unded by he Eu opean En i onmen Agency as pa o a g an wi h he Eu opean Topic
Cen e on Human heal h and he en i onmen (ETC HE) and exp esses he iews o he au ho s. The con en s o his publica ion
does no necessa ily e lec he posi ion o opinion o he Eu opean Commission o o he ins i u ions o he Eu opean Union.
Nei he he Eu opean En i onmen Agency no he Eu opean Topic Cen e on Human heal h and he en i onmen is liable o any
consequences s emming om he euse o he in o ma ion con ained in his publica ion.
How o ci e his epo :
Ho álek, J., Vlasáko á, J., Sch eibe o á, M., Schneide , P., Benešo á, N., Vlček, O. (2025). In e im ai quali y maps o EEA membe
and coope a ing coun ies o 2024. PM, O3 and NO2 spa ial es ima es (Eione Repo – ETC HE 2025/4). Eu opean Topic Cen e
on Human Heal h and he En i onmen . (h ps://doi.o g/10.5281/zenodo.17601140)
The epo is a ailable om h ps://www.eione .eu opa.eu/e cs/all-e c- epo s and h ps://zenodo.o g/communi ies/eea-
e c/?page=1&size=20.
ETC HE coo dina o : S i elsen NILU, Kjelle , No way (h ps://www.nilu.com/)
ETC HE conso ium pa ne s: Fede al En i onmen Agency/Umwel bundesam (UBA), Ae he Limi ed,
Czech Hyd ome eo ological Ins i u e (CHMI), Ins i u Na ional de l’En i onnemen Indus iel e des Risques (INERIS),
Swiss T opical and Public Heal h Ins i u e (Swiss TPH), Uni e si a Au ònoma de Ba celona (UAB),
Vlaamse Ins elling oo Technologisch Onde zoek (VITO), 4s e a Inno a S.L.U., kla FAKT e.U.
Copy igh no ice
© Eu opean Topic Cen e on Human heal h and he en i onmen , 2025
Rep oduc ion is au ho ized p o ided he sou ce is acknowledged. [C ea i e Commons A ibu ion 4.0 (In e na ional)]
Mo e in o ma ion on he Eu opean Union is a ailable on he In e ne (h p://eu opa.eu).
Eu opean Topic Cen e on
Human heal h and he en i onmen (ETC HE)
h ps://www.eione .eu opa.eu/e cs/e c-he
ETC HE Repo 2025/5 3
Con en s
Con en s ........................................................................................................................................ 3
Acknowledgemen s ....................................................................................................................... 4
Da a a ailabili y ............................................................................................................................. 4
Summa y ....................................................................................................................................... 5
1 In oduc ion ........................................................................................................................... 6
2 Pa icula e ma e .................................................................................................................. 8
2.1 PM10 annual a e age ...................................................................................................... 8
2.2 PM2.5 annual a e age ................................................................................................... 11
3 Ozone ................................................................................................................................... 16
3.1 O3 – peak season a e age o maximum daily 8-hou means ....................................... 16
4 Ni ogen dioxide .................................................................................................................. 19
4.1 NO2 annual a e age ..................................................................................................... 19
5 Conclusions .......................................................................................................................... 23
Lis o abb e ia ions .................................................................................................................... 24
Re e ences ................................................................................................................................... 25
Annex 1 Me hodology ................................................................................................... 27
A1.1 Spa ial mapping me hodology ..................................................................................... 27
A1.2 Pseudo s a ion da a es ima ion ................................................................................... 28
A1.3 Unce ain y analysis ..................................................................................................... 29
A1.4 Valida ion ..................................................................................................................... 29
A1.5 Popula ion exposu e calcula ion and es ima ion o ends ......................................... 30
A1.6 Geog aphical di ision o he conside ed Eu opean a ea used in he assessmen ...... 30
Annex 2 Da a used ........................................................................................................ 31
A2.1 Ai quali y moni o ing da a .......................................................................................... 31
A2.2 Chemical anspo modelling (CTM) da a ................................................................... 32
A2.3 Sa elli e da a ................................................................................................................ 33
A2.4 O he supplemen a y da a........................................................................................... 33
Annex 3 Technical de ails and unce ain ies o in e im maps ...................................... 34
A3.1 Pa icula e ma e PM10 ............................................................................................... 34
A3.2 Pa icula e ma e PM2.5 .............................................................................................. 35
A3.3 Ozone ........................................................................................................................... 36
A3.4 Ni ogen dioxide .......................................................................................................... 37
Annex 4 Valida ion o 2023 in e im maps and exposu e es ima es ............................. 39
A4.1 Concen a ion maps .................................................................................................... 39
A4.2 Popula ion exposu e .................................................................................................... 45
ETC HE Repo 2025/5 4
Acknowledgemen s
The ETC HE ask manage was Jan Ho álek (CHMI, Czechia). The EEA p ojec manage was Albe o
González O iz.
The ex e nal ask ETC HE e iewe was Luca Pozzoli (NILU, No way).
The e we e o he ETC HE con ibu ions. The ai quali y moni o ing da a we e ex ac ed om he AQ
e- epo ing da abase by Ma ía Colina and Jaume Ta ga (4s e a, Spain). The da a p epa a ion and he
analysis we e assis ed by Pa el Ku ü s and Lucie Školoudo á (CHMI, Czechia).
Da a a ailabili y
The in e im maps p esen ed in his epo a e a ailable in he GeoTIFF o ma on he EEA geospa ial
da a ca alogue, see below.
PM2.5, annual a e age, 2024:
h ps://sdi.eea.eu opa.eu/ca alogue/s /eng/ca alog.sea ch#/me ada a/72a465a6-4a 1-4b0c-ade5-
dd a23cc19 e (accessed 7 Oc obe 2025).
O3, peak season a e age o maximum daily 8-hou means, 2024:
h ps://sdi.eea.eu opa.eu/ca alogue/s /eng/ca alog.sea ch#/me ada a/839407de-bb7c-4cc4-91b9-
a8282b05203a (accessed 7 Oc obe 2025).
NO2, annual a e age, 2024:
h ps://sdi.eea.eu opa.eu/ca alogue/s /eng/ca alog.sea ch#/me ada a/9606e270-8ce5-4ce9-9494-
5554290ab888 (accessed 7 Oc obe 2025).
ETC HE Repo 2025/5 5
Summa y
This epo p esen s he in e im ai quali y maps o he a ea o he membe and coope a ing coun ies
o he Eu opean En i onmen Agency (EEA) o he yea 2024. These maps a e based on he non-
alida ed, up- o-da e measu emen da a and CAMS Ensemble Fo ecas modelling esul s, oge he
wi h o he supplemen a y da a.
The in e im maps and u he assessmen p esen annual a e age pa icula e ma e (bo h PM10 and
PM2.5) concen a ion, annual a e age ni ogen dioxide (NO2) concen a ion, and g ound-le el ozone
(O3) concen a ions, exp essed as he peak season a e age o maximum daily 8-hou means.
The sha e o popula ion li ing in he conside ed (i.e. p esen ed) Eu opean a ea exposed o annual
a e age PM10 concen a ion abo e he cu en (EU, 2008) limi alue (LV) o 40 µg/m3 is es ima ed o
be 0.1%; o he EU-27, no popula ion is es ima ed o be exposed o LV exceedances. In compa ison,
29% o he popula ion in bo h he conside ed Eu opean and he EU-27 was exposed o annual a e age
concen a ions abo e he e ised (EU, 2024) limi alue o 20 µg/m3 o be a ained in 2030 (LV2030).
Almos 56% o bo h he conside ed Eu opean and he EU-27 popula ions ha e been exposed o annual
a e age concen a ions abo e he WHO Ai Quali y Guideline (AQG) le el o 15 µg/m3. The popula ion-
weigh ed concen a ion o he PM10 annual a e age o 2024 o bo h he conside ed Eu opean
coun ies and o he EU-27 is es ima ed o be abou 17 µg/m3. The popula ion-weigh ed concen a ion
o he PM10 annual a e ages shows qui e a s eady dec ease o abou 0.5 µg/m3 pe yea in he pe iod
2005-2024, wi h he second lowes concen a ion in his pe iod being eco ded in 2024.
Rega ding PM2.5, i is es ima ed ha 0.1% o he popula ion li ing in he conside ed (i.e. p esen ed)
Eu opean a ea has been exposed o concen a ions abo e he EU annual LV o 25 µg/m3. Fo he EU-
27, less han 0.05% o he popula ion is es ima ed o be exposed o hose le els abo e he LV. In
compa ison, 41% o he conside ed Eu opean and 40% o he EU-27 popula ion we e exposed o
annual a e age concen a ions abo e he e ised LV2030 o 10 µg/m3. Abou 97% o he popula ion
li ing in bo h he conside ed Eu opean a ea and he EU-27 has been exposed o concen a ions abo e
he WHO AQG le el o 5 µg/m3. The popula ion-weigh ed concen a ion o he PM2.5 annual a e age
o 2024 is es ima ed o be 10 µg/m3 o bo h he EEA membe and coope a ing coun ies and he EU-
27. The popula ion-weigh ed concen a ion o he PM2.5 annual a e ages shows a ai ly s eady
dec ease o abou 0.5 µg/m3 pe yea in he pe iod 2005-2024, wi h he lowes concen a ion in his
pe iod being eco ded in 2024.
Based on he in e im map o 2024, i has been es ima ed ha 100% o he popula ion in bo h he
conside ed Eu opean a ea and he EU-27 li ed in egions whe e he O3 concen a ion was abo e he
peak season a e age o maximum daily 8-hou means o 60 µg/m3. The popula ion-weigh ed
concen a ion o he O3 peak season a e age o maximum daily 8-hou means o 2024 o bo h he
conside ed Eu opean and he EU-27 popula ion is es ima ed o be abou 89 µg/m3, which is a sligh ly
lowe alue compa ed o bo h 2023 (90 µg/m3) and 2022 (92 µg/m3).
The sha e o he popula ion li ing in he Eu opean a ea conside ed in his epo and he EU-27 a ea
exposed o annual a e age NO2 concen a ion abo e he LV o 40 µg/m3 is es ima ed o be less han
0.1%. In compa ison, 10% o bo h he conside ed Eu opean and he EU-27 popula ion we e exposed
o annual a e age concen a ions abo e he e ised LV2030 o 20 µg/m3. A ound 63% o he popula ion
li ing in bo h he conside ed Eu opean a ea and he EU-27 has been exposed o concen a ions abo e
he WHO AQG le el o 10 µg/m3. The popula ion-weigh ed concen a ion o he NO2 annual a e age
o 2024 o bo h a eas is es ima ed o be abou 12 µg/m3. The popula ion-weigh ed concen a ion o
he NO2 annual a e age shows a s eady dec ease o abou 0.7 µg/m3 pe yea in he pe iod 2005-2024,
wi h he lowes concen a ion in his pe iod eco ded in 2024.
ETC HE Repo 2025/5 6
1 In oduc ion
Eu opean-wide ai quali y (AQ) annual maps ha e been ou inely cons uc ed unde he ETC HE (and
he p e ious conso ia) since 2005 (Ho álek, 2024a and e e ences he ein). The mapping me hodology
combines moni o ing da a, chemical anspo model (CTM) esul s and o he supplemen a y da a
using a linea eg ession model ollowed by k iging o he esiduals p oduced om ha model
(‘ esidual k iging’). Sepa a e mapping laye s ( u al, u ban backg ound and u ban a ic, whe e
ele an ) a e c ea ed sepa a ely and subsequen ly me ged o he inal map. In o de o e lec he
h ee s eps applied, he me hodology is called Reg ession – In e pola ion – Me ging Mapping (RIMM).
The egula maps (i.e. maps p esen ed unde he ETC’s egula mapping epo s, e.g. Ho álek e al.,
2024a) a e based on he alida ed ai quali y moni o ing da a as s o ed in he EEA’s AQ e- epo ing
da abase (in he so-called E1a da a se ), he modelling esul s and o he supplemen a y da a. Due o
he ime schedule o he p oduc ion and a ailabili y o he alida ed AQ measu emen da a, he egula
RIMM maps o a yea Y a e ypically a ailable in May o yea Y+2. Thus, he egula 2024 maps based
on he alida ed da a will be a ailable a ound May 2026.
This epo p esen s he in e im ai quali y maps o 2024 o he a ea o he EEA membe and
coope a ing coun ies(
1
) (and he h ee mic os a es o Ando a, Monaco and San Ma ino). These maps
a e based on he non- alida ed up- o-da e (UTD) measu emen da a (as a ailable in he E2a da a se
o he AQ e- epo ing da abase) and he CAMS Ensemble Fo ecas modelling esul s, oge he wi h
o he supplemen a y da a. The eason o he p oduc ion o hese in e im maps is hei ea lie
a ailabili y. The in e im mapping app oach was p e iously de eloped and e alua ed, and consequen ly
he in e im maps o PM10, PM2.5, NO2 and ozone (O3) we e ecommended o egula p oduc ion, see
Ho álek e al. (2021a, 2021b). To o e come da a gaps in he E2a da a in some a eas, so-called pseudo
s a ions da a a e used in a eas wi h a lack o E2a s a ions, based on he eg ession ela ion be ween
he E2a da a om a yea Y and he alida ed E1a da a om a yea Y-1, oge he wi h he a io o he
modelling esul s om yea s Y and Y-1. The use o he pseudo s a ion da a in he in e im mapping is
applied o PM10, PM2.5 and NO2. Fo O3, he da a co e age o he E2a da a is la ge and he in e im O3
maps migh be cons uc ed wi hou he use o he pseudo s a ions. The in e im maps a e no p oduced
o he a ea o Tü kiye, due o he lack o E2a moni o ing da a om Tu kish s a ions.
In his epo , in e im 2024 maps o he PM10 annual a e age, he PM2.5 annual a e age, he NO2
annual a e age and he O3 indica o peak season a e age o maximum daily 8-hou means a e
p esen ed. Also, he di e ence be ween he i e-yea mean 2019-2023 (whe e a ailable) and 2024
and he in e -annual di e ence be ween 2023 and 2024 a e discussed. In addi ion, popula ion
exposu e es ima es based on he concen a ion maps a e b ie ly shown. Based on he analysis
p esen ed in Ho álek e al. (2023a), in his epo only basic exposu e es ima es a e p o ided, wi hou
de ailed in o ma ion o indi idual coun ies. The exposu e es ima es a e p esen ed o i e la ge
Eu opean egions (no he n Eu ope, wes e n Eu ope, cen al Eu ope, sou he n Eu ope and sou h-
eas e n Eu ope) (
2
), o he EU-27 and o he whole mapping a ea. Apa om his, he e olu ion o
he o e all popula ion-weigh ed concen a ion in he 20-yea pe iod 2005-2024 is also shown, whe e
a ailable.
(
1
) The EEA membe coun ies a e he 27 Membe S a es o he Eu opean Union (EU-27), Iceland, Lich ens ein, No way,
Swi ze land, and Tü kiye. The EEA coope a ing coun ies a e Albania, Bosnia and He zego ina, Mon eneg o, No h
Macedonia, Se bia, and Koso o unde he UN Secu i y Council Resolu ion 1244/99. In his epo , Koso o is conside ed
indi idually, wi hou p ejudice on i s s a us.
(
2
) No he n Eu ope: Denma k, Es onia, Finland, Iceland, La ia, Li huania, No way, Sweden; Wes e n Eu ope: Belgium,
F ance (me opoli an) no h o 45°, I eland, Luxembou g, Ne he lands; Cen al Eu ope: Aus ia, Czechia, Ge many, Hunga y,
Liech ens ein, Poland, Slo akia, Slo enia, Swi ze land; Sou he n Eu ope: Ando a, Cyp us, F ance (me opoli an) sou h o 45°,
G eece, I aly, Mal a, Monaco, Po ugal (excl. Azo es, Madei a), San Ma ino, Spain (wi hou Cana ias); Sou h-eas e n Eu ope:
Albania, Bosnia and He zego ina, Bulga ia, C oa ia, Koso o, Mon eneg o, No h Macedonia, Romania, Se bia, Tü kiye.
ETC HE Repo 2025/5 7
Apa om he 2024 in e im maps, his epo also p esen s he alida ion o he in e im maps o 2023
as p esen ed in Ho álek e al. (2024b), based on he alida ed E1a da a o 2023. I also p esen s he
compa ison o he exposu e ables based on he in e im maps o 2023 (Ho álek e al., 2024b) agains
he exposu e ables based on he egula maps (Ho álek e al., 2025).
Whe e applicable, he maps and popula ion exposu e es ima es a e p esen ed wi h espec o he
cu en EU LVs (EC, 2004; EC, 2008), he new EU LVs o be a ained by 1 Janua y 2030 (LV2030; EU, 2024)
and he cu en WHO AQG le els (WHO, 2021). Table 1.1 p esen s a compa ison o hese di e en
s anda ds.
Table 1.1 O e iew o he cu en EU limi alues (LV; EC, 2008) and new EU limi alues o
be a ained by 1 Janua y 2030 (LV2030; EU, 2024) and WHO Ai Quali y Guideline
(AQG) le els (WHO, 2021) o he pollu an s assessed in his epo
Pollu an
A e aging pe iod
LV
[µg/m3]
LV2030
[µg/m3]
WHO AQG
[µg/m3]
PM10
calenda yea
40
20
15
PM2.5
calenda yea
25
10
5
NO2
calenda yea
40
20
10
O3
peak season
(a e age o maximum daily 8-hou means)
-
-
60
Chap e s 2, 3, and 4 p esen concen a ion maps and basic es ima es o popula ion exposu e o
pa icula e ma e , O3 and NO2, espec i ely. Chap e 5 b ings he conclusions. Annex 1 desc ibes
b ie ly he me hodological aspec s (including he geog aphical dis ibu ion o he conside ed a ea in o
i e la ge egions) and Annex 2 p esen s he inpu da a applied. Annex 3 p o ides he echnical de ails
o he maps and hei unce ain y es ima es. Annex 4 p o ides he alida ion o he in e im maps and
exposu e es ima es o 2023.
ETC HE Repo 2025/5 8
2 Pa icula e ma e
2.1 PM10 annual a e age
Map 2.1 p esen s he in e im map o he PM10 annual a e age in 2024, as he esul o in e pola ion
and me ging o he sepa a e map laye s as desc ibed in Annex 1 Sec ion A1.1 ( o echnical de ails o
his map, see Annex 3, Sec ion A3.1). Red and da k ed a eas indica e concen a ions abo e he EU
annual LV o 40 µg/m3 (EC, 2008). Da k g een and ligh g een a eas show concen a ions below he
e ised EU annual LV o 20 µg/m3 ( he new EU LV o he PM₁₀ annual a e age o be a ained by 1
Janua y 2030 (LV2030); EU, 2024). Da k g een indica es he a eas whe e he PM10 annual a e age
concen a ion is below he WHO AQG le el o 15 µg/m3 (WHO, 2021).
Map 2.1 In e im concen a ion map o PM10 annual a e age, 2024
The map shows concen a ions abo e he annual LV only in u ban a eas a ound some Balkan ci ies (in
Bosnia and He zego ina and Se bia). In addi ion o hese coun ies, he e a e a eas in he Po Valley, in
I aly, and smalle disconnec ed a eas in Bosnia and He zego ina, Se bia, Albania, No h Macedonia,
G eece and Cyp us whe e PM10 concen a ions o 30-40 µg/m3 ha e been es ima ed. Mos o Eu ope
shows concen a ions below 20 µg/m3 (LV2030) wi h le els below 15 µg/m3 es ima ed o mos o
wes e n and no he n Eu ope.
The ela i e mean unce ain y (i.e. he ela i e oo mean squa e e o , RRMSE) o his map is 19% o
u al and 17% o u ban backg ound a eas (Annex 3, Table A3.2). Howe e , hese unce ain y es ima es
a e based on he non- alida ed E2a da a and a e alid only o a eas co e ed by he E2a s a ions (i.e.
no o egions co e ed by he pseudo s a ions only). The comple e alida ion o he in e im PM10 map
can only be done when he alida ed E1a da a o 2024 a e a ailable. Fo alida ion o he in e im PM10
map o 2023 as p esen ed in Ho álek e al. (2024b), e e o Annex 4, Sec ion A4.1.
Map 2.2 shows he di e ence be ween he i e-yea mean 2019-2023 and 2024 and he in e -annual
di e ence be ween 2023 and 2024 (using he egula maps o 2019-2023 and he 2024 in e im map)
ETC HE Repo 2025/5 9
o PM10 annual a e age. O ange o ed a eas show an inc ease o PM10 concen a ion in 2024, while
blue a eas show a dec ease.
Compa ed o he i e-yea mean 2019-2023, he highes inc eases in annual mean PM10 concen a ions
(> 5 µg/m3) a e obse ed mainly in pa s o G eece and I aly. Inc eases bigge han 2 µg/m3 a e
obse ed in di e en pa s o sou he n, sou h-eas e n Eu ope and cen al Eu ope. The highes
dec eases (> 5 µg/m3) we e obse ed in pa s o some Balkan coun ies. Mode a e dec eases (> 2
µg/m3) we e obse ed ac oss a la ge a ea o F ance and in se e al sca e ed egions h oughou
Eu ope. No change o sligh inc eases/dec eases o abou 2 µg/m3 a e obse ed in he es o he
mapped a ea.
Based on he map o he in e -annual di e ence be ween 2023 and 2024, inc eases bigge han
2 µg/m3 a e obse ed in pa s o sou he n, sou h-eas e n Eu ope (pa s o Po ugal, Spain, pa s o
di e en Balkan coun ies and Cyp us), cen al Eu ope (much o Hunga y, pa s o Slo enia, Aus ia,
Slo akia, Czechia, Poland, Ge many) and no he n Eu ope ( he Bal ic s a es). Dec eases we e obse ed
in pa s o F ance, I aly, Swi ze land and Se bia. No change o sligh inc eases/dec eases o abou
2 µg/m3 a e obse ed in he es o he mapped a ea.
Map 2.2 Di e ence in concen a ions be ween i e-yea mean 2019-2023 (le ) o 2023 ( igh )
and 2024 (based on he in e im map) o PM10 annual a e age
Based on he mapping esul s and he popula ion densi y da a, he popula ion exposu e es ima es
ha e been calcula ed. Table 2.1 gi es he popula ion equency dis ibu ion o a limi ed numbe o
exposu e classes and he popula ion-weigh ed concen a ion o i e la ge Eu opean egions, o EU-
27 and o he o al p esen ed a ea. The exposu e es ima e o indi idual coun ies is no p esen ed,
due o hei high unce ain y. As p esen ed in Ho álek e al. (2023a), he exposu e es ima es based on
ETC HE Repo 2025/5 16
3 Ozone
3.1 O3 – peak season a e age o maximum daily 8-hou means
In Sep embe 2021, he WHO in oduced a new AQG o O3. The new long- e m AQG le el o O₃ is se
a 60 µg/m³, exp essed as he a e age o maximum daily 8-hou mean O₃ concen a ion o he so-
called peak season. The peak season is de ined as he six consecu i e mon hs o he yea wi h he
highes six-mon h unning-a e age O3 concen a ion (WHO, 2021).
Map 3.1 p esen s he in e im 2024 map o he O3 indica o peak season a e age o maximum daily 8-
hou means. The map is a esul o me ging sepa a e u al and u ban in e pola ed map laye s as
desc ibed in Annex 1 Sec ion A1.1 ( o echnical de ails o his map, see Annex 3, Sec ion A3.3). Red
and pu ple a eas show alues abo e 100 µg/m3, while he da k g een a eas show whe e he alues o
he peak season indica o a e below he WHO AQG le el o 60 µg/m3 (WHO, 2021). Gene ally, sou he n
Eu ope shows highe concen a ions o he O3 peak season indica o han no he n Eu ope.
Map 3.1 In e im concen a ion map o O3 indica o peak season a e age o maximum daily 8-
hou means, 2024
The map shows ha in 2024 a eas wi h a peak season a e age o maximum daily 8-hou means
exceeding 60 µg/m³ co e he en i e conside ed egion. Lowes alues (< 80 µg/m³) a e obse ed in
no he n Eu ope (pa s o Sweden, Finland, Es onia and La ia), as well as in I eland, and in a la ge a ea
o F ance. Highe alues (> 100 µg/m³) a e eco ded in no he n I aly, cen al Spain, and a ious pa s
o he Balkan coun ies and Cyp us. Values o 80–100 µg/m³ a e obse ed in he emaining mapped
a ea o Eu ope.
The ela i e mean unce ain y (RRMSE) o his map is 7% o u al and 8% o u ban backg ound a eas
(Annex 3, Table A3.5). Howe e , hese unce ain y es ima es a e based on he non- alida ed E2a da a
and a e alid only o a eas co e ed by he E2a s a ions. The comple e alida ion o he in e im O3 map
can only be done when he alida ed E1a da a o 2024 a e a ailable.
ETC HE Repo 2025/5 17
Map 3.2 shows he in e -annual di e ence be ween 2024 and 2023 o he O3 indica o peak season
a e age o maximum daily 8-hou means. O ange o ed a eas show an inc ease in O3 concen a ion in
2024, while blue a eas show a dec ease.
Compa ed o 2023, mos egions in Scandina ia, I eland, cen al Eu ope, Spain and I aly expe ienced
no signi ican changes o only sligh a ia ions (±4 µg/m³) in he O3 peak season a e age o maximum
daily 8-hou means. A no iceable inc ease in he O3 peak season a e age is obse ed in he Balkan
coun ies, pa icula ly in G eece, Bulga ia and Romania, Cyp us, sou he n Poland and pa s o Hunga y.
Con e sely, a dec ease is e iden in la ge a eas o F ance, pa s o Ge many, I aly, Swi ze land,
Po ugal, Spain, he Bal ic s a es and pa s o Scandina ia. A dec ease g ea e han 10 µg/m³ is
obse ed in la ge a eas o C oa ia and Bosnia and He zego ina.
Map 3.2 Di e ence in concen a ions be ween 2024 (based on he in e im map) and 2023 o O3
indica o peak season a e age o maximum daily 8-hou means
Based on he mapping esul s and he popula ion densi y da a, he popula ion exposu e es ima e has
been calcula ed. Table 3.1 gi es he popula ion equency dis ibu ion o a limi ed numbe o
exposu e classes and he popula ion-weigh ed concen a ion o la ge Eu opean egions, o EU-27
and o he o al mapping a ea. The exposu e es ima e o indi idual coun ies is no p esen ed, due
o hei high unce ain y. As p esen ed in Ho álek e al. (2023a), he exposu e es ima es based on
in e im maps gi e good esul s o he o al a ea and he EU-27, bu somewha poo e esul s o
indi idual coun ies.
Based on he in e im map o 2024, i has been es ima ed ha 100% o bo h he conside ed Eu opean
popula ion and EU-27 popula ion li ed in a eas whe e he O3 concen a ion was abo e he peak season
a e age o maximum daily 8-hou means o 60 µg/m3. The popula ion-weigh ed concen a ion o he
O3 peak season a e age o maximum daily 8-hou means o 2024 o bo h he conside ed Eu opean
and he EU-27 popula ion is es ima ed o be a ound 89 µg/m3.
ETC HE Repo 2025/5 18
Table 3.1 Popula ion exposu e and popula ion-weigh ed concen a ion, O3 indica o peak season
a e age o maximum daily 8-hou means, 2024, based on an in e im map
A ea
Popula ion
[inhbs·1000]
O3 – peak season indica o , exposed popula ion, 2024 [%]
O3 – peak s. indic.
< 60
µg/m3
60 -80
µg/m3
80 -90
µg/m3
90 -100
µg/m3
100 -120
µg/m3
> 120
µg/m3·d
Pop. weigh ed
[µg/m3inhbs]
No he n Eu ope
34 237
70.45
29.50
0.05
78.3
Wes e n Eu ope
86 767
45.90
53.40
0.69
0.01
81.1
Cen al Eu ope
166 272
0.24
53.97
44.54
1.25
90.2
Sou he n Eu ope
143 256
5.38
24.25
45.09
25.27
0.00
94.3
Sou h-eas e n Eu ope
46 096
19.13
38.57
38.59
3.71
87.7
To al
476 628
16.6
41.7
33.3
8.4
0.0
88.7
EU-27
444 765
16.6
41.7
32.8
8.9
0.0
88.8
No e: The pe cen age alue "0.0" indica es ha an exposed popula ion exis s, bu i is small and es ima ed o be less han 0.05%. Emp y cells mean no popula ion
in exposu e. 5-yea mean, i.e. 5-yea mean 2019-2023. Di ., i.e. di e ence concen a ions be ween 2024 and 5-yea mean 2019-2023.
Figu e 3.1 shows, o he whole conside ed a ea, he equency dis ibu ion o he O3 peak season
a e age o maximum daily 8-hou means o popula ion exposu e classes o 1 µg/m3. The highes
popula ion equency is ound o classes be ween ca 75 and 95 µg/m3. Fo classes abo e 95 µg/m3, a
sha p decline o he popula ion equency can be seen.
Figu e 3.1 Popula ion equency dis ibu ion, O3 indica o peak season a e age o maximum daily
8-hou means, 2024, based on he in e im map. The WHO AQG le el (60 µg/m3) is
ma ked by he g een line
The map o he O3 peak season indica o has been p epa ed o he hi d yea only, so no e olu ion in
a longe pe iod can be shown. I is es ima ed ha he mean popula ion-weigh ed concen a ion o he
peak season indica o shows a sligh ly lowe alue o 2024 (89 µg/m3), compa ed o bo h 2023
(90 µg/m3) and 2022 (92 µg/m3).
ETC HE Repo 2025/5 19
4 Ni ogen dioxide
4.1 NO2 annual a e age
Map 4.1 p esen s he in e im map o he NO2 annual a e age in 2024, as he esul o in e pola ion
and me ging o he sepa a e map laye s as desc ibed in Annex 1 Sec ion A1.1 ( o echnical de ails o
his map, see Annex 3, Sec ion A3.4). Red and pu ple a eas indica e concen a ions abo e he annual
LV o 40 µg/m3 (EC, 2008). G een a eas show concen a ions below he e ised EU annual LV o 20
µg/m3 (LV2030, o be a ained by 2030). Da k g een a eas indica e concen a ions below 10 µg/m3, being
he WHO AQG le el (WHO, 2021).
Acco ding o Map 4.1, no a eas whe e NO2 concen a ions exceeded he annual LV o 40 µg/m³ we e
obse ed. Some ci ies, pa icula ly capi als in sou he n and sou h-eas e n Eu ope, show NO2 le els
abo e 20 µg/m³ (new LV2030). The u banized a eas o se e al majo ci ies all wi hin he ange o annual
a e age NO2 concen a ions be ween 10 and 20 µg/m³. Mos o Eu ope shows NO2 le els below he
AQG le el o 10 µg/m³, while a la ge egion wi h concen a ions be ween 10 and 20 µg/m³ is ound in
he Po Valley.
I should be no ed ha he in e pola ed map is c ea ed a 1 km esolu ion only. Al hough he u ban
a ic map laye is used in he map c ea ion, he a ic loca ions a e smoo hed in he inal map a
1 km esolu ion. Thus, he map as such e e s o he u al and u ban backg ound si ua ions, while he
alues abo e he NO2 annual LV occu mos ly a local ho spo s such as dense a ic loca ions. Such
concen a ions (al hough hey occu ed a some u ban a ic loca ions in 2024) a e no isible in he
1 km esolu ion Map 4.1.
Map 4.1 In e im concen a ion map o NO2 annual a e age, 2024
The ela i e mean unce ain y (RRMSE) o his map is 30% o u al a eas and 24% o u ban
backg ound a eas (Annex 3, Table A3.7). Howe e , hese unce ain y es ima es a e based on he non-
alida ed E2a da a and a e alid only o a eas co e ed by he E2a s a ions. The comple e alida ion o
he in e im NO2 map can only be done when he alida ed E1a da a o 2024 a e a ailable. Fo such
ETC HE Repo 2025/5 20
alida ion o he in e im NO2 map o 2023 as p esen ed in Ho álek e al. (2024b), see Annex 4, Sec ion
A4.1.
Map 4.2 shows he di e ence be ween i e-yea mean 2019-2023 and 2024 and he in e -annual
di e ence be ween 2024 and 2023 (using he egula maps o 2019-2023 and he 2024 in e im map)
o he NO2 annual a e age. O ange o ed a eas show an inc ease o NO2 concen a ion in 2024, while
blue a eas show a dec ease.
Compa ed o he i e-yea mean 2019-2023, no change o sligh inc eases/dec eases o abou 2 µg/m3
a e obse ed in mos o he Eu opean mapped a ea. On he o he hand, ela i ely con inuous a eas in
no he n I aly, no he n Ge many and he Benelux coun ies show a dec ease in annual a e age NO2
bigge han 2 µg/m3.
Based on he map o he in e -annual di e ence be ween 2024 and 2023, he e is no change o a sligh
inc ease/dec ease (±2 µg/m³) in annual a e age NO2 concen a ions in almos he en i e conside ed
(i.e. p esen ed) Eu opean a ea. Ne e heless, inc eases g ea e han 2 µg/m³ a e e iden in pa s o
G eece, Bulga ia, No h Macedonia, and Albania, while dec eases o mo e han 2 µg/m³ we e obse ed
mainly in no he n I aly.
Map 4.2 Di e ence in concen a ions be ween i e-yea mean 2019-2023 (le ) o 2023 ( igh )
and 2024 (based on he in e im map) o NO2 annual a e age
Based on he mapping esul s and he popula ion densi y da a, he popula ion exposu e es ima e has
been calcula ed. Table 4.1 gi es he popula ion equency dis ibu ion o a limi ed numbe o
exposu e classes and he popula ion-weigh ed concen a ions o la ge Eu opean egions, o EU-27
and o he o al mapping a ea. The exposu e es ima es o indi idual coun ies a e no p esen ed, due
o hei high unce ain y. As p esen ed in Ho álek e al. (2023a), he exposu e es ima es based on
ETC HE Repo 2025/5 21
in e im maps gi e good esul s o he o al a ea and he EU-27, bu somewha poo e esul s o
indi idual coun ies.
Based on he in e im map, i is es ima ed ha less han 0.1% o bo h he conside ed Eu opean and he
EU-27 popula ion has been exposed o concen a ions abo e he EU annual LV o 40 µg/m3. In
compa ison, 10% o bo h he conside ed Eu opean and he EU-27 popula ion we e exposed o annual
a e age concen a ions abo e he e ised LV2030 o 20 µg/m3. Mos o hem li ed in sou he n and
sou h-eas e n Eu ope. A ound 63% o bo h he conside ed Eu opean and he EU-27 popula ion has
been exposed o concen a ions exceeding 10 µg/m3 (being he WHO AQG le el). The popula ion-
weigh ed concen a ion o he NO2 annual a e age o 2024 o bo h he conside ed Eu opean and he
EU-27 popula ion is es ima ed o be 12.4 µg/m3.
Table 4.1 Popula ion exposu e and popula ion-weigh ed concen a ion, NO2 annual a e age,
2024, based on in e im map
A ea
Popula ion
[inhbs·1000]
NO2 – annual a e age, exposed popula ion, 2024 [%]
Popula ion-weigh ed
concen a ion
< 10
µg/m3
10-20
µg/m3
20-30
µg/m3
30-40
µg/m3
40-45
µg/m3
> 45
µg/m3
2024
5-yea
mean
Di .
No he n Eu ope
34 237
84.1
15.5
0.5
6.8
7.8
-1.0
Wes e n Eu ope
86 767
44.7
49.3
4.9
1.0
11.1
13.8
-2.7
Cen al Eu ope
166 272
34.6
61.0
4.3
0.1
12.0
14.2
-2.2
Sou he n Eu ope
143 256
29.3
51.2
18.1
1.2
0.1
0.1
14.2
16.3
-2.0
Sou h-eas e n Eu ope
46 096
22.5
62.1
14.6
0.8
14.4
16.0
-1.5
To al
476 628
37.0
52.9
9.3
0.7
0.0
0.0
12.4
14.3
-1.9
EU-27
444 765
37.4
52.4
9.3
0.7
0.0
0.0
12.4
14.5
-2.1
No e: The pe cen age alue "0.0" indica es ha an exposed popula ion exis s, bu i is small and es ima ed o be less han 0.05%. Emp y cells mean no popula ion
in exposu e. 5-yea mean, i.e. 5-yea mean 2019-2023. Di ., i.e. di e ence concen a ions be ween 2024 and 5-yea mean 2019-2023.
Figu e 4.1 shows, o he whole conside ed a ea, he popula ion equency dis ibu ion o exposu e
classes wi h a wid h o 1 µg/m3. One can see he highes popula ion equency o classes be ween 6
and 17 µg/m3, con inuous decline o popula ion equency o classes be ween 18 and 25 µg/m3 and
con inuous mild decline o popula ion equency o classes be ween 25 and 40 µg/m3.
Figu e 4.1 Popula ion equency dis ibu ion, NO2 annual a e age 2024, based on he in e im map.
The WHO AQG le el (10 µg/m3) is ma ked by he g een line, he e ised EU annual LV2030
(20 µg/m3) is ma ked by he yellow line, and he EU annual LV (40 µg/m3) is ma ked by
he ed line
ETC HE Repo 2025/5 22
Fo changes in he popula ion-weigh ed concen a ion o he NO2 annual a e age in he pe iod 2005-
2024, see Figu e 4.2. Fo he p e ious yea s, mapping esul s as p esen ed in Ho álek e al. (2025 and
e e ences he ein) ha e been used. As he egula maps a e no a ailable o all yea s, in addi ion an
al e na i e mapping esul s p epa ed based on a subse o s a ions o he pu pose o end analysis
2005-2019 (Ho álek e al., 2022) a e also p esen ed. Again, he popula ion-weigh ed concen a ion o
he whole a ea including he Uni ed Kingdom is p esen ed o he whole pe iod including 2024, o
consis ency easons. The NO2 concen a ion (in e ms o annual a e age) shows a dec ease o abou
0.7 µg/m3 pe yea . One can see ha he in e im esul s o 2024 show he lowes es ima es in he
p esen ed pe iod.
Figu e 4.2 Popula ion-weigh ed concen a ion o NO2 annual a e age in 2005-2024, based on bo h
he egula ( ed) and he end analysis (blue) mapping esul s (whe e a ailable), and
wi h in e im esul s o he yea 2024
ETC HE Repo 2025/5 23
5 Conclusions
The epo p esen s he in e im 2024 maps o PM10 annual a e age, PM2.5 annual a e age, NO2 annual
a e age and he O3 indica o peak season a e age o maximum daily 8-hou means. The maps ha e
been p oduced based on he non- alida ed E2a (UTD) da a o he AQ e- epo ing da abase, he CAMS
Ensemble Fo ecas modelling da a and o he supplemen a y da a. Toge he wi h he concen a ion
maps, he di e ence maps be ween i e-yea mean 2019-2023 and 2024 and be ween he yea s 2023
and 2024 a e p esen ed (using he 2019-2023 egula and he 2024 in e im maps), as well as basic
exposu e es ima es based on he in e im maps.
Rega ding PM10 annual a e age, he map indica es ha concen a ions abo e he annual LV occu
mainly in u ban a eas o Balkan ci ies. Addi ionally, ele a ed PM10 le els (30-40 µg/m3) a e es ima ed
in pa s o he Po Valley in I aly and o he sca e ed a eas in sou h-eas e n Eu ope, while mos o
wes e n and no he n Eu ope shows concen a ions below 20 µg/m3 ( he e ised LV2030).
PM2.5 le els abo e he annual LV occu in sca e ed u ban a eas o Bosnia and He zego ina.
Exceedances o he ILV a e obse ed in he Po Valley (I aly), he K akow–Ka owice–Os a a indus ial
egion, and pa s o he Balkan coun ies. In cen al and sou h-eas e n Eu ope, concen a ions ange
mainly be ween 5-15 µg/m³, while in sou he n Eu ope hey a e mos ly 5-10 µg/m³, wi h some a eas
below he WHO AQG le el (5 µg/m³). Cen al and wes e n Eu ope show p edominan ly alues below
10 µg/m³ ( he e ised LV2030), and no he n Eu ope mos ly below 5 µg/m³.
In he case o O3, he map shows ha in 2024 a eas wi h a peak season a e age o maximum daily 8-
hou means exceeding 60 µg/m³ (wi h he peak season de ined as he six consecu i e mon hs o he
yea wi h he highes six-mon h unning-a e age O3 concen a ion) co e he en i e conside ed egion.
Lowes alues (< 80 µg/m³) a e obse ed in pa s o no he n Eu ope as well as in I eland, and in a la ge
a ea o F ance. Highe alues (> 100 µg/m³) a e eco ded in no he n I aly, cen al Spain, and a ious
pa s o he Balkan coun ies and Cyp us. Values o 80–100 µg/m³ a e obse ed in he emaining
mapped a ea o Eu ope.
In he case o NO2, no a eas exceeded he annual LV o 40 µg/m³ o NO2, based on he 1 km esolu ion
inal map (al hough concen a ions abo e he annual LV occu ed a some u ban a ic loca ions,
which a e smoo hed in his inal map esolu ion). Some ci ies, especially capi als in sou he n and sou h-
eas e n Eu ope, show NO2 le els abo e 20 µg/m³ ( he e ised LV2030). The u banized a eas o se e al
majo ci ies all wi hin he ange o annual a e age NO2 concen a ions be ween 10 and 20 µg/m³.
Mos o Eu ope shows NO2 le els below he AQG le el o 10 µg/m³, while a la ge egion wi h
concen a ions be ween 10 and 20 µg/m³ is ound in he Po Valley.
Unce ain y es ima es based on he c oss- alida ion o he E2a da a ha e been pe o med o all
in e im maps, showing qui e sa is ac o y esul s in gene al. Howe e , hese unce ain y es ima es a e
based on he non- alida ed E2a da a and a e alid o a eas co e ed by he E2a measu emen s only.
The comple e alida ion o he in e im maps should ca ied ou when he alida ed E1a da a o 2023
become me a ailable.
In he epo , popula ion exposu e o only la ge Eu opean egions, EU-27 and he o al conside ed
a ea has been p esen ed. The mo e de ailed exposu e es ima es o pa icula Eu opean coun ies will
be p esen ed in 2026, in he ETC HE egula mapping epo on he 2024 ai quali y maps c ea ed based
on he alida ed da a E1a.
ETC HE Repo 2025/5 24
Lis o abb e ia ions
Abb e ia ion
Name
Re e ence
AQ
Ai Quali y
AQG
Ai Quali y Guideline
CLC
CORINE Land Co e
h ps://land.cope nicus.eu
/pan-eu opean/co ine-
land-co e
CORINE
Co-ORdina ed IN o ma ion on he En i onmen
h ps://land.cope nicus.eu
/pan-eu opean/co ine-
land-co e
CTM
Chemical T anspo model
ECMWF
Eu opean Cen e o Medium-Range Wea he
Fo ecas s
h ps://www.ecmw .in /
EBAS
EMEP da aBASe
h ps://ebas.nilu.no/
EEA
Eu opean En i onmen Agency
www.eea.eu opa.eu
EMEP
Eu opean Moni o ing and E alua ion P og amme
h ps://www.emep.in /
ETC HE
Eu opean Topic Cen e on Human heal h and he
En i onmen
h ps://www.eione .eu op
a.eu/e cs
EU
Eu opean Union
h ps://eu opean-
union.eu opa.eu
GMTED
Global mul i- esolu ion e ain ele a ion da a
GRIP
Global Roads In en o y Da ase
ILV
Indica i e Limi Value
JRC
Join Resea ch Cen e
h ps://ec.eu opa.eu/in o/
depa men s/join -
esea ch-cen e_en
LV
Limi Value
h p://eu -
lex.eu opa.eu/LexU iSe /L
exU iSe .do?u i=OJ:L:200
8:152:0001:0044:EN:PDF
LV2030
e ised limi alues o be a ained by 1 Janua y 2030
h ps://eu -
lex.eu opa.eu/legal-
con en /EN/TXT/PDF/?u i=
OJ:L_202402881
NILU
Clima e and en i onmen al esea ch ins i u e
h ps://www.nilu.no/
NO2
Ni ogen dioxide
O3
Ozone
ORNL
Oak Ridge Na ional Labo a o y
h ps://www.o nl.go /
PM10
Pa icula e Ma e wi h a diame e o 10
mic ome es o less
PM2.5
Pa icula e Ma e wi h a diame e o 2.5
mic ome es o less
R2
Coe icien o de e mina ion
RIMM
Reg ession – In e pola ion – Me ging Mapping
RMSE
Roo Mean Squa e E o
RRMSE
Rela i e Roo Mean Squa e E o
UTC
Coo dina ed Uni e sal Time
WHO
Wo ld Heal h O ganiza ion
h ps://www.who.in /
ETC HE Repo 2025/5 25
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C essie, N., 1993, S a is ics o spa ial da a, Wiley se ies, New Yo k.
Danielson, J. J. and Gesch, D. B., 2011, Global mul i- esolu ion e ain ele a ion da a 2010
(GMTED2010), U.S. Geological Su ey Open-File Repo , pp. 2011-1073
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ambien ai quali y and cleane ai o Eu ope, OJ L 152, 11.06.2008, 1-44
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EEA, 2025, Ai Quali y e-Repo ing. Ai quali y da abase (h ps://www.eea.eu opa.eu/da a-and-
maps/da a/aqe epo ing-8). Da a ex ac ed in Feb ua y 2025.
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(h ps://land.cope nicus.eu/pan-eu opean/co ine-land-co e /clc2018) accessed 19 No embe 2020.
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2024 on ambien ai quali y and cleane ai o Eu ope ( ecas ), OJ L, 20.11.2024, p. 1-70
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2025.
Eu os a , 2020, JRC-GEOSTAT 2018 g id da ase , Popula ion dis ibu ion da ase
(h ps://ec.eu opa.eu/eu os a /web/gisco/geoda a/ e e ence-da a/popula ion-dis ibu ion-
demog aphy/geos a ) accessed 12 Ap il 2024.
Gilbe , R. O., 1987, S a is ical Me hods o En i onmen al Pollu ion Moni o ing, Van Nos and
Reinhold, New Yo k.
Ho álek, J., e al., 2021a, Po en ial use o CAMS modelling esul s in ai quali y mapping unde
ETC/ATNI, Eione Repo ETC/ATNI 2019/17 (h ps://doi.o g/10.5281/zenodo.4627762) accessed 15
June 2021.
ETC HE Repo 2025/5 32
Table A2.1 Numbe o s a ions used in in e im mapping 2024 pe s a ion ype, o PM10 (le ) and
PM2.5 ( igh )
S a ion ype
PM10
PM2.5
E1a 2023
E2a 2024
E1a 2023
E2a 2024
To al
Fo
eg ession
Fo
pseudo
2024
Mapping
2024
To al
Fo
eg ession
Fo
pseudo
2024
Mapping
2024
Ru al backg ound
410
304
106
319
285
200
85
220
U ban/subu b. backg .
1512
1178
334
1232
1032
760
272
817
U ban/subu b. a ic
803
663
140
696
495
399
96
432
Fo he PM2.5 mapping, in addi ion o he PM2.5 s a ions, 95 u al backg ound, 70 u ban/subu ban
backg ound and 271 u ban/subu ban a ic PM10 E2a 2024 s a ions (a loca ions wi hou PM2.5
measu emen o 2024) ha e been also used o he pu pose o calcula ing he pseudo PM2.5 s a ion
da a (see Eq. A1.5).
Table A2.2 shows he numbe o s a ions used in he in e im mapping o O3 and NO2. In he O3 in e im
mapping, only E2a 2024 s a ions a e used. No pseudo s a ions o O3 a e used due o qui e comple e
spa ial co e age o he E2a O3 da a.
Table A2.2 Numbe o s a ions used in in e im mapping 2024 pe s a ion ype, o O3 and NO2
S a ion ype
O3
NO2
E2a 2024
E1a 2023
E2a 2024
Mapping
2024
To al
Fo
eg ession
Fo
pseudo
2024
Mapping
2024
Ru al backg ound
498
460
398
62
407
U ban/subu b. backg .
1113
1376
1231
145
1277
U ban/subu b. a ic
–
1231
881
350
913
A2.2 Chemical anspo modelling (CTM) da a
The CAMS Ensemble Fo ecas da a as p o ided by he Cope nicus A mosphe e Moni o ing Se ice
(CAMS) a a egional scale o e Eu ope ha e been used. The Eu opean egional p oduc ion consis s o
an ensemble o ele en ai quali y models un ope a ionally. All models use he same CAMS-REG
an h opogenic emissions and cu en me eo ology om he ope a ional ECMWF IFS o ecas . The
models p o ide (along wi h o he p oduc s) a 96-hou o ecas made a ailable a 08:00 UTC he day o
he o ecas . The o ecas da a p oduc is a ailable on an hou ly ime esolu ion and a a spa ial
esolu ion o 0.1° x 0.1°, which co esponds oughly o 5-10 km (W–E) x 10 km (S–N). Each model
o ecas is combined in o an ensemble o ecas by aking he median o all used models. Fo u he
de ails see ECMWF (2025).
In his epo , he CAMS Ensemble Fo ecas da a ( o he lead hou 0-23) o 2023 and 2024 ha e been
used (CAMS, 2025). All he models used in he ensemble we e un using he CAMS-REG- 5.1 REF2
2.0.1 emissions (co esponding o yea 2018) o mos o he yea 2023; in No embe 2023 emissions
we e upda ed o CAMS-REG- 6.1 co esponding o yea 2022 and in No embe /Decembe 2024 o
CAMS_REG. 7 co esponding o yea 2023 (ECMWF, 2025). Fo mo e in o ma ion on emissions, see
Kuenen e al., 2024. All modelling da a ha e been agg ega ed in o he annual s a is ics and con e ed
ETC HE Repo 2025/5 33
in o he e e ence EEA 1 km ( o PM and NO2) and 10 km ( o O3) g ids. The pollu an s and pa ame e s
used a e he same as hose used o he moni o ing da a, as desc ibed in Sec ion A2.1.
A2.3 Sa elli e da a
Da a om he TROPOsphe ic Moni o ing Ins umen (TROPOMI) onboa d o he Sen inel-5 P ecu so
sa elli e (Vee kind e al., 2012) we e used. Thei spa ial esolu ion is app oxima ely 5.5 km by 3.5 km.
The p oduc used is he S5P_OFFL_L2__NO2 p oduc ( an Ge en e al., 2019, 2020) and i p o ides
he oposphe ic e ical column densi y o ni ogen dioxide (NO2), i.e. a e ically in eg a ed alue
o e he en i e oposphe e. All o e passes o a speci ic day we e hen mosaicked and g idded in o
he e e ence EEA 1 km g id in he ETRS89 / ETRS-LAEA (EPSG 3035) p ojec ion. The daily g idded iles
ha e been subsequen ly a e aged o an annual mean. The annual mean has been agg ega ed om
cloud- ee high-quali y (qa_ alue > 0.75) daily da a only. The pa ame e used is
NO2 – annual a e age oposphe ic e ical column densi y (VCD) [numbe o NO2 molecules pe
cm2 o ea h su ace], yea s 2023 and 2024.
A2.4 O he supplemen a y da a
Me eo ological da a
The me eo ological da a used a e he ECWMF da a ex ac ed om he CDS (Clima e Da a S o e,
h ps://cds.clima e.cope nicus.eu/cdsapp#!/home). Speci ically, he hou ly da a o he eanalysed
da a se ERA5-Land in 0.1°x0.1° esolu ion ha e been used. In he coas al a eas (whe e he da a om
ERA5-Land a e no a ailable), he same pa ame e s om he eanalysed da a se ERA5 in 0.25°x0.25°
esolu ion ha e been applied. The hou ly da a ha e been de i ed in o he pa ame e s needed,
agg ega ed in o he annual s a is ics and con e ed in o he e e ence EEA 1 km ( o PM and NO2) and
10 km ( o O3) g ids. Fo de ails, see Ho álek e al. (2025). Me eo ological pa ame e s used a e wind
speed (annual mean o 2024, in m.s-1), su ace ne sola adia ion (annual mean o daily sum o 2024,
in MWs.m-2) and ela i e humidi y (annual mean o 2024, in pe cen age).
Al i ude
The al i ude da a ield (in m) o Global Mul i- esolu ion Te ain Ele a ion Da a 2010 (GMTED2010) has
been used, wi h an o iginal g id esolu ion o 15 a cseconds coming om U.S. Geological Su ey Ea h
Resou ces Obse a ion and Science, see Danielson and Gesch (2011). The da a we e con e ed in o
he EEA e e ence g ids in 1 km and 10 km esolu ions. Nex o his, ano he agg ega ion based on he
1 km g id cells has been execu ed, i.e. he a e age o he ci cle wi h a adius o 5 km, calcula ed as a
loa ing a e age o all 1 km g id cells.
Land co e
CORINE Land Co e (CLC) 2018 – g id 100 m, Ve sion 2020_20 (EU, 2020) is used. The 44 CLC classes
ha e been e-g ouped in o he 8 mo e gene al classes. In his pape , i e o hese gene al classes a e
used, namely high densi y esiden ial a eas (HDR), low densi y esiden ial a eas (LDR), ag icul u al
a eas (AGR), na u al a eas (NAT), and a ic a eas (TRAF). Fo de ails, see Ho álek e al. (2024a). Two
agg ega ions a e used, i.e., in o 1 km g id and in o he ci cle wi h adius o 5 km. The agg ega ed g id
alue ep esen s o each gene al class he o al a ea o his class as pe cen age o he o al a ea o he
1 km x 1 km squa e o he ci cle wi h adius o 5 km.
Popula ion densi y and Road da a
Popula ion densi y (in inhabi an s/km2) is based on JRC-Geos a 2018 g id da ase , Eu os a (2020). Fo
egions no included in he JRC-Geos a 2018 da ase , GHS popula ion g id o 2020 (JRC, 2023) scaled
o he e e ence yea 2018 is used. Fo de ails, see Ho álek e al. (2024a). GRIP ec o oad ype da a
is used (Meije e al., 2018). Based on hese da a (i.e., bu e s a ound he oads), a ic map laye s
(Sec ion 2.1) a e me ged in o he inal maps (Ho álek e al., 2024a).
ETC HE Repo 2025/5 34
Annex 3 Technical de ails and unce ain ies o in e im
maps
This Annex 3 p esen s di e en echnical de ails on he in e im maps p esen ed in his epo . Sec ions
A3.1, A3.2, A3.3 and A3.4 gi e echnical de ails and unce ain y es ima es o he 2024 in e im maps
o PM10, PM2.5, O3 and NO2, espec i ely.
A3.1 Pa icula e ma e PM10
This sec ion p esen s he echnical de ails and unce ain y es ima es o he PM10 2024 annual a e age
in e im map as p esen ed in Map 2.1.
Like in Ho álek e al. (2021b), i s , he pseudo s a ions da a ha e been es ima ed. The es ima es ha e
been calcula ed based on he E1a measu emen da a o 2023, he CAMS Ensemble Fo ecas modelling
da a o 2023 and 2024, and he eg ession ela ion wi h he E2a measu emen da a o 2024. Table
A3.1 p esen s he eg ession coe icien s de e mined o pseudo s a ions da a es ima ion, based on
he 1482 u al and u ban/subu ban backg ound and 663 u ban/subu ban a ic s a ions ha ha e
bo h E1a 2023 and E2a 2024 measu emen s a ailable (see Sec ions A1.2 and A2.1). Nex o his, i
p esen s he s a is ics showing he en a i e quali y o he es ima e.
Table A3.1: Pa ame e s and s a is ics o he linea eg ession model o he gene a ion o pseudo
PM10 da a in u al and u ban backg ound and u ban a ic a eas, o PM10 annual
a e age 2024
c (cons an ) 0.7 0.5
a1 (PM10 annual mean 2022, E1a da a) 0.578 0.734
a2 (PM10 annual mean 2022 * CAMS a io 2023/2022) 0.394 0.242
Adjus ed R20.88 0.87
S anda d E o [µg/m3]2.0 2.2
Linea
eg ession
model (LRM,
Eq. 2.4)
PM10 – Annual a e age
Ru al and u ban
backg ound a eas
U ban a ic
a eas
Based on he E2a da a and pseudo da a, CAMS Ensemble Fo ecas modelling da a and o he
supplemen a y da a as used in he egula mapping, he in e im PM10 annual a e age map o 2024
has been c ea ed (see Map 2.1). Table A3.2 p esen s he es ima ed pa ame e s o he linea eg ession
models (c, a1, a2,…) and o he esidual k iging (nugge , sill, ange) and includes he s a is ical indica o s
o bo h he eg ession and he k iging o i s esiduals.
Table A3.2 shows ha he unce ain y o he in e im map o PM10 annual a e age exp essed by RMSE
is 2.5 µg/m3 o he u al a eas, 3.1 µg/m3 o he u ban backg ound a eas and 3.5 µg/m3 o he u ban
a ic a eas. The ela i e mean unce ain y (Rela i e RMSE) o his map is 19.2% o u al, 17.4% o
u ban backg ound and 17.9% o u ban a ic a eas. Howe e , hese unce ain y es ima es a e based
on he non- alida ed E2a da a and a e alid only o a eas co e ed by he E2a s a ions. The comple e
alida ion o he in e im PM10 map can only be done when he alida ed E1a da a o 2024 a e
a ailable.
ETC HE Repo 2025/5 35
Table A3.2 Pa ame e s and s a is ics o he linea eg ession model and o dina y k iging in u al,
u ban backg ound and u ban a ic a eas o he in e im map o PM10 annual a e age
2024
Ru al a eas U ban b. a eas U ban . a eas
c (cons an ) 2.34 1.01 1.78
a1 (log. CAMS-ENS FC model) 0.776 0.71 0.511
a2 (al i ude GMTED) -0.00016
a3 ( ela i e humidi y) -0.043
a4 (wind speed) -0.019 -0.057
a5 (land co e NAT1) -0.0009
Adjus ed R20.68 0.41 0.40
S anda d E o [µg/m3]0.22 0.25 0.25
nugge 0.010 0.014 0.021
sill 0.043 0.041 0.023
ange [km] 100 160 320
RMSE [µg/m3]2.5 3.1 3.5
Rela i e RMSE [%] 19.2 17.4 17.9
Bias (MPE) [µg/m3]0.2 0.1 -0.1
R2 o c oss.- al. eg . equa ion 0.73 0.70 0.70
Slope o c oss- al. eg . equa ion 0.81 0.76 0.69
In e cep o c oss- al. eg . equa ion 2.6 4.4 5.9
Linea eg esion
model (LRM,
Eq. 2.1)
O dina y k iging
(OK) o LRM
esiduals
LRM + OK o i s
esiduals
PM10
Annual a e age
A3.2 Pa icula e ma e PM2.5
This sec ion p esen s he echnical de ails and unce ain y es ima es o he PM2.5 2024 annual a e age
in e im map as p esen ed in Map 2.3.
Like in Ho álek e al. (2023b), he pseudo s a ions da a o wo ypes ha e been es ima ed a i s , i.e.
based on he PM2.5 E1a measu emen da a o 2023, he CAMS Ensemble Fo ecas modelling da a o
2023 and 2024, and he eg ession ela ion wi h he PM2.5 E2a measu emen da a o 2024 (see Eq.
A1.4) and based on he PM10 E2a measu emen da a o 2024, di e en supplemen a y da a, and he
eg ession ela ion wi h he PM2.5 E2a measu emen da a o 2024 (see Eq. A1.5). Table A3.3 p esen s
he eg ession coe icien s de e mined o hese pseudo s a ions da a es ima ions.
Table A3.3 Pa ame e s and s a is ics o he linea eg ession model o he gene a ion o pseudo
PM2.5 da a in u al and u ban backg ound and u ban a ic a eas o PM2.5 annual
a e age 2024, using PM2.5 E1a da a o 2023 ( op) and PM10 E2a da a o 2024 (bo om)
c (cons an ) 0.6 0.5
a1 (PM2.5 annual mean 2023, E1a measu emen da a) 0.487 0.514
a2 (PM2.5 annual mean 2023 * CAMS a io 2024/2023) 0.462 0.457
Adjus ed R20.89 0.90
S anda d E o [µg/m3]1.3 1.2
c (cons an ) 20.8 37.8
b (PM10 annual mean 2024, E2a measu emen da a) 0.616 0.470
a1 (su ace sola adia ion 2024) -0.0030 -0.0039
a2 (la i ude) -0.237 -0.493
a3 (longi ude) 0.096 0.116
Adjus ed R20.84 0.75
S anda d E o [µg.m-3]1.5 1.9
Linea
eg ession
model (LRM,
Eq. 2.4)
PM2.5 - Annual a e age
Ru al and u ban
backg ound a eas
U ban a ic
a eas
Linea
eg esion
model (LRM,
Eq. 2.5)
ETC HE Repo 2025/5 36
The es ima es based on he PM2.5 E1a da a o 2023 ha e been calcula ed using 960 u al and
u ban/subu ban backg ound and 399 u ban/subu ban a ic s a ions ha ha e bo h E1a 2023 and E2a
2024 da a a ailable, while he es ima es based on he PM10 E2a da a o 2024 using 964 u al and
u ban/subu ban backg ound and 394 u ban/subu ban a ic s a ions ha ha e bo h PM10 and PM2.5
E2a 2024 da a a ailable.
Simila ly as in Ho álek e al. (2023b), he es ima es based on he PM2.5 da a o 2023 show s onge
co ela ion wi h he PM2.5 da a o 2024, compa ed o he es ima es based on he PM10 da a o 2024.
Leading om his, he pseudo da a es ima es based on he PM10 da a o 2024 ha e been applied only
in places wi h no pseudo da a es ima es based on he PM2.5 da a o 2023. Fo he numbe o PM2.5
da a and pseudo PM2.5 da a o bo h ypes applied in he in e im map c ea ion, see Sec ion 3.1.
Based on he E2a da a and pseudo da a, CAMS Ensemble Fo ecas modelling da a and o he
supplemen a y da a as used in he egula mapping, he in e im PM2.5 annual a e age map o 2024
has been c ea ed. Table A3.4 p esen s he es ima ed pa ame e s o he linea eg ession models (c, a1,
a2,…) and o he esidual k iging (nugge , sill, ange) and includes he s a is ical indica o s o bo h he
eg ession and he k iging o i s esiduals.
Table A3.4 Pa ame e s and s a is ics o he linea eg ession model and o dina y k iging in u al,
u ban backg ound and u ban a ic a eas o he in e im map o PM2.5 annual a e age
2024
Ru al a eas U ban b. a eas U ban . a eas
c (cons an ) 0.76 0.68 0.81
a1 (log. CAMS-ENS-FC model) 0.728 0.72 0.673
a2 (al i ude GMTED) -0.00022
a3 (wind speed) -0.055
a4 (land co e NAT1) -0.0011
Adjus ed R20.60 0.50 0.60
S anda d E o [µg/m3]0.27 0.26 0.23
nugge 0.030 0.015 0.013
sill 0.075 0.044 0.055
ange [km] 1000 90 1000
RMSE [µg/m3]1.5 2.1 2.1
Rela i e RMSE [%] 20.5 20.1 20.4
Bias (MPE) [µg/m3]0.2 0.0 0.0
R2 o c oss.- al. eg . equa ion 0.76 0.72 0.71
Slope o c oss- al. eg . equa ion 0.79 0.74 0.71
In e cep o c oss- al. eg . equa ion 1.7 2.7 3.0
Linea
eg esion
model (LRM,
Eq. 2.1)
O dina y
k iging (OK)
o LRM
LRM + OK o
i s esiduals
PM2.5 – Annual a e age
Table A3.4 shows ha he unce ain y o he in e im map o PM2.5 annual a e age exp essed by RMSE
is 1.5 µg/m3 o he u al a eas and 2.1 µg/m3 o bo h he u ban backg ound and he u ban a ic
a eas. The ela i e mean unce ain y (Rela i e RMSE) o his map is 20.5% o u al a eas, 20.1% o
he u ban backg ound a eas and 20.4% o he u ban a ic a eas. Howe e , hese unce ain y
es ima es a e based on he non- alida ed E2a da a and a e alid only o a eas co e ed by he E2a
s a ions. The comple e alida ion o he in e im PM2.5 map can only be done when he alida ed E1a
da a o 2024 a e a ailable.
A3.3 Ozone
Simila ly as in Ho álek e al. (2024b), no pseudo s a ions o O3 ha e been used, due o a qui e comple e
spa ial co e age o he E2a da a. Based on he E2a da a, CAMS Ensemble Fo ecas modelling da a and
ETC HE Repo 2025/5 37
o he supplemen a y da a as used in he egula mapping, he in e im map o he O3 indica o peak
season a e age o maximum daily 8-hou means o 2024 has been c ea ed (see Map 3.1). Table A3.5
p esen s he es ima ed pa ame e s o he linea eg ession models (c, a1, a2,…) and o he esidual
k iging (nugge , sill, ange) and includes he s a is ical indica o s o he eg ession and he k iging o
i s esiduals.
Table A3.5 Pa ame e s and s a is ics o he linea eg ession model and o dina y k iging in u al
and u ban backg ound a eas o he in e im map o O3 indica o peak season a e age o
maximum daily 8-hou means o 2024
c (cons an ) -9.1 18.3
a1 (CAMS-ENS-FC model) 1.10 0.80
a2 (al i ude GMTED) 0.01
a3 (wind speed) -1.4
a4 (s. sola adia ion) n. sign. 0.0009
Adjus ed R20.57 0.44
S anda d E o [µg/m3·d]6.5 8.1
nugge 24 20
sill 41 41
ange [km] 790 80
RMSE [[µg/m3·d] 6.3 6.8
Rela i e RMSE [%] 6.9 7.6
Bias (MPE) [µg/m3·d]0.0 0.1
R2 o c oss.- al. eg . equa ion 0.60 0.60
Slope o c oss- al. eg . equa ion 0.62 0.62
In e cep o c oss- al. eg . equa ion 34.3 33.4
Linea eg esion
model (LRM,
Eq. 2.1)
O d. k ig. (OK) o
LRM esiduals
LRM + OK o i s
esiduals
O3 – Peak season a e age o maximum daily 8-hou means
Ru al backg ound
a eas
U ban backg ound
a eas
Table A3.5 shows ha he unce ain y o he in e im map o O3 indica o peak season a e age o
maximum daily 8-hou means exp essed by RMSE is 6.3 µg/m3 o he u al a eas and 6.8 µg/m3 o
he u ban backg ound a eas. These unce ain y es ima es a e based on he non- alida ed E2a da a and
a e alid only o a eas co e ed by he E2a s a ions. The comple e alida ion o he in e im O3 map can
only be done when he alida ed E1a da a o 2024 a e a ailable.
A3.4 Ni ogen dioxide
As a i s s ep o he in e im NO2 annual a e age 2024 map c ea ion, he pseudo s a ions da a ha e
been es ima ed, based on he E1a measu emen da a o 2023, he Sen inel-5P sa elli e da a o 2023
and 2024, and he eg ession ela ion wi h he E2a measu emen 2024 da a. Table A3.6 p esen s he
eg ession coe icien s de e mined o pseudo s a ions da a es ima ion.
Table A3.6 Pa ame e s and s a is ics o he linea eg ession model o gene a ion o pseudo NO2
da a in u al and u ban backg ound and u ban a ic a eas, o NO2 annual a e age
2024
c (cons an ) 0.4 0.4
a1 (NO2 annual mean 2023, E1a da a) 0.691 0.932
a2 (NO2 annual mean 2023 * Sen inel-5P a io 2024/2023) 0.249 n.sign.
Adjus ed R20.93 0.92
S anda d E o [µg/m3]1.5 2.2
Linea
eg ession
model (LRM,
Eq. 2.4)
NO2 – Annual a e age
Ru al and u ban
backg ound a eas
U ban a ic
a eas
ETC HE Repo 2025/5 38
The pseudo s a ions da a es ima ion is based on he 1629 u al and u ban/subu ban backg ound and
881 u ban/subu ban a ic s a ions ha ha e bo h E1a 2023 and E2a 2024 measu emen s a ailable
(see Sec ions A1.2 and A2.1). Apa om his, i gi es he s a is ics showing he en a i e quali y o he
es ima e.
Based on he E2a da a and pseudo da a, CAMS Ensemble Fo ecas modelling da a, Sen inel-5P sa elli e
da a and o he supplemen a y da a as used in he egula mapping, he in e im NO2 annual a e age
map o 2024 has been c ea ed (see Map 4.1). Table A3.7 p esen s he es ima ed pa ame e s o he
linea eg ession models (c, a1, a2,…) and o he esidual k iging (nugge , sill, ange) and includes he
s a is ical indica o s o bo h he eg ession and he k iging o i s esiduals.
Table A3.7 Pa ame e s and s a is ics o he linea eg ession model and o dina y k iging in u al,
u ban backg ound and u ban a ic a eas o he in e im map o NO2 annual a e age
2024
Ru al a eas U b. b. a eas U b. . a eas
c (cons an ) 4.4 11.5 17.25
a1 (CAMS-ENS-FC model) 0.329 0.176 n.sign.
a6 (sa elli e Sen inel-5P) 1.16 1.554 2.041
a2 (al i ude) -0.0054
a3 (al i ude_5km_ adius) 0.0050
a4 (wind speed) -0.72 -1.635 -1.923
a7 (popula ion*1000) 0.00082 0.00016
a8 (NAT_1km) -0.0401
a9 (AGR_1km) -0.0214
a10 (TRAF_1km) 0.0557
a11 (LDR_5km_ adius) n.sign. n.sign. 0.0991
a12 (HDR_5km_ adius) n.sign. 0.1920
a13 (NAT_5km_ adius) -0.0271
Adjus ed R20.70 0.50 0.39
S anda d E o [µg/m3]2.0 3.8 6.1
nugge 3 8 14
sill 4 11 28
ange [km] 990 90 9
RMSE [µg/m3]1.7 3.2 5.4
Rela i e RMSE [%] 30.4 24.0 24.4
Bias (MPE) [µg/m3]0.0 0.0 -0.2
R2 o c oss.- al. eg . equa ion 0.76 0.63 0.52
Slope o c oss- al. eg . equa ion 0.74 0.63 0.53
In e cep o c oss- al. eg . equa ion 1.4 4.9 10.3
O dina y k iging
(OK) o LRM
esiduals
LRM + OK o i s
esiduals
Annual a e age
NO2
Linea
eg esion model
(LRM, Eq. 2.1)
Table A3.7 shows ha he unce ain y o he in e im map o NO2 annual a e age exp essed by RMSE
is 1.7 µg/m3 o he u al a eas, 3.2µg/m3 o he u ban backg ound a eas, and 5.4 µg/m3 o he u ban
a ic a eas, espec i ely. The ela i e mean unce ain y (Rela i e RMSE) o his map is 30.4% o u al
a eas, 24% o u ban backg ound a eas and 24.4% o u ban a ic a eas. Howe e , like o o he
pollu an s, hese unce ain y es ima es a e based on he non- alida ed E2a da a and a e alid only o
a eas co e ed by he E2a s a ions. The comple e alida ion o he in e im NO2 map can only be done
when he alida ed E1a da a o 2024 a e a ailable.
ETC HE Repo 2025/5 39
Annex 4 Valida ion o 2023 in e im maps and exposu e
es ima es
This Annex 4 p esen s he alida ion o he 2023 in e im maps p oduced using he up- o-da e E2a da a
(EEA, 2024) as p esen ed in Ho álek e al. (2024b), agains he alida ed E1a da a (EEA, 2025). Nex o
his, i p esen s he exposu e ables calcula ed using he in e im 2023 maps and alida es hem agains
he exposu e es ima es calcula ed using he egula 2023 maps as p esen ed in Ho álek e al. (2025).
A4.1 Concen a ion maps
This sec ion e alua es he concen a ion in e im maps agains he E1a da a, using c oss- alida ion.
PM10
Table A4.1 p esen s he e alua ion o he in e im PM10 annual a e age 2023 map, agains he E1a
s a ion da a o 2023. Addi ionally, i also p esen s he c oss- alida ion e alua ion o he egula PM10
annual a e age 2023 map (Ho álek e al., 2025) o he same subse s o he E1a s a ion da a, o
compa able easons.
Table A4.1 Valida ion o in e im (le ) and egula ( igh ) map o PM10 annual a e age 2023
showing RMSE, RRMSE, bias, R2 and linea eg ession om alida ion sca e plo s in
u al backg ound ( op), u ban backg ound (middle) and u ban a ic a eas (bo om),
agains wo alida ion se s o s a ions. Uni s: µg/m3 excep o RRMSE and R2
RMSE RRMSE Bias
R2Reg . eq.
RMSE
RRMSE Bias
R2Reg . eq.
E1a s a ions wi h E2a da a 2.3 18.2% 0.3 0.742 y = 0.831x + 2.4 2.3 18.5% 0.2 0.739 y = 0.831x + 2.4
E1a s a ions wi h no E2a da a 3.1 22.1% 0.1 0.649 y = 0.726x + 3.9 3.0 21.8% 0.0 0.664 y = 0.765x + 3.2
E1a s a ions wi h E2a da a 3.2 18.3% 0.1 0.696 y = 0.754x + 4.3 3.3 18.9% 0.3 0.684 y = 0.789x + 3.9
E1a s a ions wi h no E2a da a 4.0 20.3% -0.5 0.554 y = 0.551x + 8.4 2.9 14.8% -0.2 0.530 y = 0.582x + 8.2
E1a s a ions wi h E2a da a 3.3 17.6% -0.2 0.691 y = 0.681x + 5.8 3.3 17.6% 0.1 0.693 y = 0.711x + 5.5
E1a s a ions wi h no E2a da a 4.0 19.2% -0.6 0.539 y = 0.613x + 7.4 4.0 19.6% -0.1 0.526 y = 0.652x + 7.1
PM10 – Annual A e age
U ban a ic
In e im map
A ea
Regula map
Valida ion se
Ru al
U ban
backg ound
One can see ha , in gene al, he unce ain y o he in e im map is he same o only sligh ly wo se
compa ed o he unce ain y o he egula map.
Addi ionally, he alida ion o he E2a da a and he pseudo s a ion da a used in he in e im PM10
mapping has been pe o med. Table A4.2 shows he alida ion o he E2a and he pseudo da a agains
he E1a s a ion da a in he loca ions o hese s a ions.
Table A4.2: Valida ion o E2a and pseudo s a ion da a showing RMSE, RRMSE, bias, R2 and linea
eg ession om alida ion sca e plo s o u al backg ound ( op), u ban/subu ban
backg ound (middle) and u ban/subu ban a ic s a ions (bo om), PM10 annual
a e age 2023. Valida ion by E1a s a ion da a. Uni s: µg/m3 excep o RRMSE and R2
S a ion ype E alua ed se Valida ion se N RMSE RRMSE Bias R2Reg . eq.
E2a s a ions E1a s a ions wi h E2a da a 286 0.7 5.9% 0.1 0.974 y = 1.015x - 0.1
Pseudo s a ions E1a s a ions loca ed a pseudo s a ions 95 1.5 11.1% 0.2 0.876 y = 1.037x - 0.3
E2a s a ions E1a s a ions wi h E2a da a 1152 1.1 6.1% 0.0 0.964 y = 0.982x + 0.3
Pseudo s a ions E1a s a ions loca ed a pseudo s a ions 270 2.1 10.4% -0.5 0.897 y = 0.834x + 2.8
E2a s a ions E1a s a ions wi h E2a da a 649 1.1 5.7% -0.1 0.968 y = 0.955x + 0.7
Pseudo s a ions E1a s a ions loca ed a pseudo s a ions 81 2.1 10.2% -0.6 0.858 y = 0.917x + 1.1
PM10 – Annual A e age
Ru al backg ound
U ban/subu ban
backg ound
U ban/subu ban
a ic
ETC HE Repo 2025/5 40
In gene al, he esul s show simila o be e ag eemen o he pseudo da a wi h he E1a da a,
compa ed o he alida ion o he pseudo s a ions p esen ed in Ho álek e al. (2021b), which
ecommended he use o he pseudo s a ions.
Map A4.1 shows he di e ence be ween he in e im and he egula maps o he PM10 annual a e age
2023, o u al and u ban backg ound map laye s. One can see he g ea es di e ences in Balkan and
Cyp us, i.e. in he a eas wi h he lack o he E1a s a ions.
Map A4.1 Di e ence be ween in e im and egula map o PM10 annual a e age 2023 in u al (le )
and u ban backg ound ( igh ) a eas. U ban map laye is applicable in u ban a eas only
PM2.5
Table A4.3 shows he e alua ion o he in e im PM2.5 annual a e age 2023 map, agains he E1a s a ion
da a o 2023. Addi ionally, i also p esen s he c oss- alida ion e alua ion o he egula PM2.5 annual
a e age 2023 map (Ho álek e al., 2025) o he same subse s o he E1a s a ion da a, o compa able
easons.
ETC HE Repo 2025/5 41
Table A4.3 Valida ion o in e im (le ) and egula ( igh ) map o PM2.5 annual a e age 2023
showing RMSE, RRMSE, bias, R2 and linea eg ession om alida ion sca e plo s in
u al backg ound ( op), u ban backg ound (middle) and u ban a ic a eas (bo om),
agains wo alida ion se s o s a ions. Uni s: µg/m3 excep o RRMSE and R2
RMSE RRMSE Bias
R2Reg . eq. RMSE RRMSE Bias R2Reg . eq.
E1a s a ions wi h E2a da a 1.4 18.5% 0.2 0.814 y = 0.723x + 2.3 1.4 18.3% 0.2 0.808 y = 0.775x + 1.9
E1a s a ions wi h no E2a da a 2.9 31.7% -0.6 0.615 y = 0.591x + 3.2 2.6 28.3% -0.5 0.691 y = 0.666x + 2.6
E1a s a ions wi h E2a da a 2.8 26.9% 0.2 0.704 y = 0.781x + 2.4 2.1 20.9% 0.1 0.694 y = 0.778x + 2.4
E1a s a ions wi h no E2a da a 2.7 22.8% 0.1 0.645 y = 0.759x + 3.0 2.5 21.0% 0.2 0.698 y = 0.801x + 2.6
E1a s a ions wi h E2a da a 2.0 20.4% -0.1 0.774 y = 0.718x + 2.7 2.0 20.5% 0.0 0.754 y = 0.706x + 2.9
E1a s a ions wi h no E2a da a 2.3 20.7% -0.3 0.671 y = 0.769x + 2.4 2.3 20.3% -0.2 0.682 y = 0.788x + 2.2
PM2.5 – Annual A e age
U ban a ic
In e im map
Regula map
Valida ion se
Ru al
U ban
backg ound
One can see ha he unce ain y o he in e im map is a he simila o only sligh ly wo se le el as he
unce ain y o he egula map.
Addi ionally, he alida ion o he E2a da a and he pseudo s a ion da a used in he in e im PM2.5
mapping has been pe o med. Table A4.4 shows he alida ion o he E2a and he pseudo da a, agains
he E1a s a ion da a in he loca ions o hese s a ions.
Table A4.4 Valida ion o E2a and pseudo s a ion da a showing RMSE, RRMSE, bias, R2 and linea
eg ession om alida ion sca e plo s o u al backg ound ( op), u ban/subu ban
backg ound (middle) and u ban/subu ban a ic s a ions (bo om), PM2.5 annual
a e age 2023. Valida ion by E1a s a ion da a. Uni s: µg/m3 excep o RRMSE and R2
S a ion ype E alua ed se Valida ion se N RMSE RRMSE Bias R2Reg . eq.
E2a s a ions E1a s a ions wi h E2a da a 185 0.6 7.9% 0.0 0.963 y = 0.955x + 0.3
Pseudo s a ions E1a s a ions loca ed a pseudo s a ions 89 1.4 14.7% -0.1 0.915 y = 0.888x + 1.0
E2a s a ions E1a s a ions wi h E2a da a 759 0.8 8.0% 0.0 0.955 y = 0.981x + 0.2
Pseudo s a ions E1a s a ions loca ed a pseudo s a ions 232 1.6 12.9% -0.2 0.879 y = 0.907x + 1.0
E2a s a ions E1a s a ions wi h E2a da a 396 0.5 5.2% -0.1 0.984 y = 0.961x + 0.3
Pseudo s a ions E1a s a ions loca ed a pseudo s a ions 78 1.4 11.7% -0.2 0.902 y = 1.001x - 0.2
PM2.5 – Annual A e age
Ru al backg ound
U ban/subu ban
backg ound
U ban/subu ban
a ic
In gene al, he esul s show simila o be e ag eemen o he pseudo da a wi h he E1a da a,
compa ed o he alida ion o he pseudo s a ions p esen ed in Ho álek e al. (2023b), which
ecommended he use o he pseudo s a ions.
Map A4.2 shows he di e ence be ween he in e im and he egula maps o he PM2.5 annual a e age
2023, o u al and u ban backg ound map laye s. One can see he g ea es di e ences in Balkan and
Cyp us, i.e. in he a eas wi h he lack o he E1a s a ions.
Eu opean Topic Cen e on
Human Heal h and he En i onmen
h ps://www.eione .eu opa.eu/e cs/e c-he
The Eu opean Topic Cen e on Human Heal h and
he En i onmen (ETC HE) is a conso ium o
Eu opean ins i u es unde con ac o he Eu opean
En i onmen Agency.
