High NO2 Concentrations Measured by Passive Samplers in Czech Cities: Unresolved Aftermath of Dieselgate?

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378041%3A_____%2F21%3A00552853" target="_blank" >RIV/68378041:_____/21:00552853 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68407700:21220/21:00350368

Výsledek na webu

<a href="https://www.mdpi.com/2073-4433/12/5/649" target="_blank" >https://www.mdpi.com/2073-4433/12/5/649</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/atmos12050649" target="_blank" >10.3390/atmos12050649</a>

Jazyk výsledku

angličtina

Název v původním jazyce

High NO2 Concentrations Measured by Passive Samplers in Czech Cities: Unresolved Aftermath of Dieselgate?

Popis výsledku v původním jazyce

This work examines the effects of two problematic trends in diesel passenger car emissions-increasing NO2/NOx ratio by conversion of NO into NO2 in catalysts and a disparity between the emission limit and the actual emissions in everyday driving-on ambient air quality in Prague. NO2 concentrations were measured by 104 membrane-closed Palmes passive samplers at 65 locations in Prague in March-April and September-October of 2019. NO2 concentrations measured by city stations during those periods were comparable with the average values during 2016-2019. The average measured NO2 concentrations at the selected locations, after correcting for the 18.5% positive bias of samplers co-located with a monitoring station, were 36 mu g/m(3) (range 16-69 mu g/m(3), median 35 mu g/m(3)), with the EU annual limit of 40 mu g/m(3) exceeded at 32% of locations. The NO2 concentrations have correlated well (R-2 = 0.76) with the 2019 average daily vehicle counts, corrected for additional emissions due to uphill travel and intersections. In addition to expected hot-spots at busy intersections in the city center, new ones were identified, i.e., along a six-lane road V Holesovickach. Comparison of data from six monitoring stations during 15 March-30 April 2020 travel restrictions with the same period in 2016-2019 revealed an overall reduction of NO2 and even a larger reduction of NO. The spatial analysis of data from passive samplers and time analysis of data during the travel restrictions both demonstrate a consistent positive correlation between traffic intensity and NO2 concentrations along/near the travel path. The slow pace of NO2 reductions in Prague suggests that stricter vehicle NOx emission limits, introduced in the last decade or two, have so far failed to sufficiently reduce the ambient NO2 concentrations, and there is no clear sign of remedy of Dieselgate NOx excess emissions.

Název v anglickém jazyce

High NO2 Concentrations Measured by Passive Samplers in Czech Cities: Unresolved Aftermath of Dieselgate?

Popis výsledku anglicky

This work examines the effects of two problematic trends in diesel passenger car emissions-increasing NO2/NOx ratio by conversion of NO into NO2 in catalysts and a disparity between the emission limit and the actual emissions in everyday driving-on ambient air quality in Prague. NO2 concentrations were measured by 104 membrane-closed Palmes passive samplers at 65 locations in Prague in March-April and September-October of 2019. NO2 concentrations measured by city stations during those periods were comparable with the average values during 2016-2019. The average measured NO2 concentrations at the selected locations, after correcting for the 18.5% positive bias of samplers co-located with a monitoring station, were 36 mu g/m(3) (range 16-69 mu g/m(3), median 35 mu g/m(3)), with the EU annual limit of 40 mu g/m(3) exceeded at 32% of locations. The NO2 concentrations have correlated well (R-2 = 0.76) with the 2019 average daily vehicle counts, corrected for additional emissions due to uphill travel and intersections. In addition to expected hot-spots at busy intersections in the city center, new ones were identified, i.e., along a six-lane road V Holesovickach. Comparison of data from six monitoring stations during 15 March-30 April 2020 travel restrictions with the same period in 2016-2019 revealed an overall reduction of NO2 and even a larger reduction of NO. The spatial analysis of data from passive samplers and time analysis of data during the travel restrictions both demonstrate a consistent positive correlation between traffic intensity and NO2 concentrations along/near the travel path. The slow pace of NO2 reductions in Prague suggests that stricter vehicle NOx emission limits, introduced in the last decade or two, have so far failed to sufficiently reduce the ambient NO2 concentrations, and there is no clear sign of remedy of Dieselgate NOx excess emissions.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

30304 - Public and environmental health

Projekt

<a href="/cs/project/EF16_019%2F0000798" target="_blank" >EF16_019/0000798: Healthy Aging in Industrial Environment HAIE</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Atmosphere

ISSN

2073-4433

e-ISSN

2073-4433

Svazek periodika

12

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

27

Strana od-do

649

Kód UT WoS článku

000653471400001

EID výsledku v databázi Scopus

2-s2.0-85107195253