Joint MSC-E/CHMI Technical note 1/2012
"Assessment of Heavy Metal Pollution Levels in the Czech Republic (EMEP case study)" 


Stations measuring Cd concentrations in air and in precipitation at the Czech national monitoring network. Green circles denote all stations, white circles - priority stations selected for the analysis, red squares - EMEP stations

The Czech Republic provided information on cadmium concentrations in air from 72 national monitoring stations, and concentrations in precipitation from 30 stations. Eight background regional stations with co-located measurements (i.e., measurements of concentrations both in air and in precipitation) were selected for the detailed analysis of pollution levels in the country. Two of them (Kosetice and Svratouch) report annually information on heavy metal concentrations and deposition to EMEP.

Modelling of cadmium concentrations and deposition was carried out for 2007 with spatial resolutions of 50x50 km and 5x5 km. Calculations with resolution 50x50 km were performed on the base of EMEP officially reported emission data. For simulations with resolution 5x5 km emission data for the Czech Republic were provided by national experts, while for other countries the EMEP emissions were re-gridded from 50-km to 5-km resolution.

Calculated fields of cadmium concentrations in air and total deposition generally reflected spatial distribution of the emissions. Patterns of pollution levels simulated with 5x5 km and 50x50 km resolution were similar. However, maps with finer resolution demonstrated much more detailed picture of country-scale pollution levels.

 

Spatial distribution of emission data with resolution 50x50 km (left) and 5x5 km (right). Location of priority stations is depicted by circles


Calculated concentrations of Cd in air with resolution 50x50 km (left) and 5x5 km (right) in the Czech Republic in 2007
Calculated total deposition of Cd with resolution 50x50 km (left) and 5x5 km (right) in the Czech Republic in 2007

 

Refinement of spatial resolution of emission and meteorological data resulted to reduction of discrepancies between modelled and measured annual mean concentrations of Cd at the priority stations.


Annual mean observed and modelled concentrations of Cd in 2007 at priority Czech monitoring stations

 

Time series of calculated concentrations modelled with different spatial resolution are compared with time series of concentrations observed at the Czech stations. Analysis of selected short-term pollution episodes allows to examine factors responsible for Cd levels in the atmosphere. Analysis of some of episodes is available in technical and status reposts. Further analysis will be continued.

Time series of modelled and observed concentrations of Cd in 2007 at priority Czech monitoring stations.