In accordance with Annex 2 of Decree …/2024, which implements certain provisions of the Act on the Public Hydrometeorological Service, the Czech Hydrometeorological Institute (CHMI) provides current operational (unverified) hourly data on outdoor air pollutants (pollutant concentrations from monitoring stations with automated measurement programs, as specified by Act No. 201/2012 Coll., on Air Protection).
The data made available include key pollutants with ambient air quality limits under current legislation: nitrogen dioxide (NO₂), nitrogen oxides (NOₓ), ground-level ozone (O₃), suspended particles PM₁₀ and PM₂.₅, sulfur dioxide (SO₂), and carbon monoxide (CO).
The data are based on measurements taken at stations owned by CHMI.
In accordance with Annex 2 of Decree …/2024, which implements certain provisions of the Act on the Public Hydrometeorological Service, the Czech Hydrometeorological Institute (CHMI) has made operational (unverified) primary and aggregated data available for outdoor air pollutants (pollutant concentrations from automatic monitoring stations, provided in the scope and temporal aggregations specified by Act No. 201/2012 Coll., on Air Protection).
The data include key pollutants with ambient air limit values under current legislation: arsenic (As), benzene, benzo[a]pyrene, cadmium (Cd), carbon monoxide (CO), nickel (Ni), nitrogen dioxide (NO₂), nitrogen oxides (NOₓ), ground-level ozone (O₃), lead (Pb), suspended particles PM₁₀, suspended particles PM₂.₅, and sulfur dioxide (SO₂).
The data are based on measurements from CHMI-owned stations since 1969. Primary data are provided in measurement intervals of 30 minutes, 1 hour, or 24 hours, depending on the type of measurement. Aggregated data are calculated from the aforementioned primary data and include the following: daily averages, monthly averages, annual averages, and the number of exceedances of ambient air limit values. Preliminary data include air quality information that is older than one hour. Verified data can be found in the dataset *Air Quality Measurements – Verified Data*, in accordance with the data verification process. Verification is carried out once a year, no later than July 1st (YYYY-1).
In accordance with Annex 2 of Decree …/2024, which implements certain provisions of the Act on the Public Hydrometeorological Service, the Czech Hydrometeorological Institute (CHMI) has made verified primary and aggregated data available for outdoor air pollutants (pollutant concentrations from Concentration of pollutants from monitoring stations with automatic and manual programs, provided in the scope and temporal aggregations specified by Act No. 201/2012 Coll., on Air Protection).
The data include key pollutants with ambient air limit values under current legislation: arsenic (As), benzene, benzo[a]pyrene, cadmium (Cd), carbon monoxide (CO), nickel (Ni), nitrogen dioxide (NO₂), nitrogen oxides (NOx), ground-level ozone (O₃), lead (Pb), suspended particles PM10, suspended particles PM2.5, and sulfur dioxide (SO₂).
The data are based on measurements from CHMI-owned stations since 1969. Primary data are provided in measurement intervals of 30 minutes, 1 hour, or 24 hours, depending on the type of measurement. Aggregated data are calculated from the aforementioned primary data and include the following: daily averages, monthly averages, annual averages, and the number of exceedances of ambient air limit values.
The most recent verified data available date back approximately 18 months from the current date, in accordance with the data verification process.
Concentrations of air pollutants in the 1x1 km grid, years 2018–2022. Limit values for the protection of human health SO2 - 4th highest 24-hour SO2 concentration [µg.m-3], PM10 - annual average concentration [µg.m-3], PM10 - 36th highest 24-hour average concentration [µg.m-3], PM2.5 - annual average concentration [µg. m-3], NO2 - annual average concentration [µg.m-3], O3 - 26th highest maximum daily 8-hour moving average concentration averaged over 3 years, 2019-2021 [µg.m-3], As - annual average concentration [ng.m-3], Cd - annual average concentration [ng.m-3], benzo[a]pyrene - annual average concentration [ng.m-3], benzene - annual average concentration [µg.m-3]. Areas with exceedances of limit values without O3. Areas with exceedances of the limit values with the inclusion of O3. Limit values for the protection of ecosystems and vegetation O3 - AOT40 exposure index values, 5-year average, 2019-2023 [µg.m-3], NOx - annual average concentration [µg.m-3], SO2 - annual (annual average) and winter period (winter average) [µg.m-3].
Legislation (Act 201/2012 Coll., as amended) requires that the primary source of assessment be the results of stationary measurements. Measured concentrations may be supplemented by modelling and indicative measurements in the production of pollutant maps to ensure that the resulting estimate provides sufficient information on the spatial distribution of air pollutant concentrations. In the Czech Republic, the Eulerian chemical dispersion model CAMx is mainly used, additionally also the Gaussian model SYMOS and the European Eulerian model EMEP. In addition, in the case of individual pollutants, e.g. altitude or population density.
Act No. 201/2012 Coll., on Air Protection, as amended
Concentrations of air pollutants in the 1x1 km grid, year 2023. Limit values for the protection of human health SO2 - 4th highest 24-hour SO2 concentration [µg.m-3], PM10 - annual average concentration [µg.m-3], PM10 - 36th highest 24-hour average concentration [µg.m-3], PM2.5 - annual average concentration [µg. m-3], NO2 - annual average concentration [µg.m-3], O3 - 26th highest maximum daily 8-hour moving average concentration averaged over 3 years, 2019-2021 [µg.m-3], As - annual average concentration [ng.m-3], Cd - annual average concentration [ng.m-3], benzo[a]pyrene - annual average concentration [ng.m-3], benzene - annual average concentration [µg.m-3]. Areas with exceedances of limit values without O3. Areas with exceedances of the limit values with the inclusion of O3. Limit values for the protection of ecosystems and vegetation O3 - AOT40 exposure index values, 5-year average, 2019-2023 [µg.m-3], NOx - annual average concentration [µg.m-3], SO2 - annual (annual average) and winter period (winter average) [µg.m-3].
Legislation (Act 201/2012 Coll., as amended) requires that the primary source of assessment be the results of stationary measurements. Measured concentrations may be supplemented by modelling and indicative measurements in the production of pollutant maps to ensure that the resulting estimate provides sufficient information on the spatial distribution of air pollutant concentrations. In the Czech Republic, the Eulerian chemical dispersion model CAMx is mainly used, additionally also the Gaussian model SYMOS and the European Eulerian model EMEP. In addition, in the case of individual pollutants, e.g. altitude or population density.
Act No. 201/2012 Coll., on Air Protection, as amended
In accordance with Act 123/1998 Coll. on free access to environmental information, as amended, the CHMI has provided verified primary and aggregated data on outdoor air pollutants. These are the main pollutants with limit values according to current legislation: arsenic (As), benzene, benzo[a]pyrene, cadmium (Cd), carbon monoxide (CO), nickel (Ni), nitrogen dioxide (NO2), nitrogen oxides (NOX), ground-level ozone (O3), lead (Pb), particulate matter (PM10), particulate matter (PM2.5), sulphur dioxide (SO2). The data are based on measurements at stations owned by the CHMI for the period 1969-2022. The primary data are presented in measurement intervals of 30 min, 1 h or 24 h, depending on the type of measurement. Aggregated data are calculated from the above primary data. These data are: daily mean values, monthly mean values, annual mean values and the number of exceedances of the limit values for the protection of human health. Verified data for subsequent calendar years from 2020 will always be available by 1 July of the following year.