EEMEP ASSESSMENT REPORT   EEMEP ASSESSMENT REPORT NATIONAL CONTRIBUTION CCZECH REPUBLIC MMilan Váňa1), Karel Dejmal1), Pavel Machálek2), Ivan Holoubek3) 1)    Czech Hydrometeorological Institute - Košetice Observatory 2)    Czech Hydrometeorological Institute-Department of Emission and Sources 3)    RECETOX-TOCOEN and Associates

Location of the Czech EMEP stations

Total emissions of principal pollutants in the Czech Republic (1980 - 2001)

Total emissions of HMs and POPs (1990 – 2001) a) preliminary data

Trend of SO2S in the atmosphere Košetice 1989-2001

Trend of SO4S in the atmosphere Košetice 1989-1998

Sector distribution of SO4S concentrations (Košetice 1989-1996)

Trend of NO2N in the atmosphere Svratouch 1980-2001

Trend of surface ozone in the atmosphere Košetice 1992-2001

Sector distribution of surface ozone concentrations (Košetice 1993-1996)

Number of days, when the 8-hour running mean of surface ozone concentration exceeded 160 µg/m3 (Košetice, Svratouch 1993-2001)

Number of days, when the 8-hour running mean of surface ozone concentration exceeded 120 µg/m3 (Košetice, Svratouch 1993-2001)

Trend of cyklohexan concentrations in the atmosphere (Košetice 1995-2001)

Sector distribution of ethane concentrations (Košetice 1993-1996)

Trend of PAHs concentrations in the atmosphere (gas Trend of PAHs concentrations in the atmosphere (gas. phase+aerosol) (Košetice 1996-2000)

Trend of SO4S deposition (Svratouch 1978-2000)

Sector distribution of SO4S deposition (Svratouch 1988-1995)

Comparison model versus observation - SO2S concentration in the air (Košetice 1989-1996) y = 0.45x+3.27 Max. dif. = 129.1 Min. dif. = -94.1 RMSE = 9.6 BIAS = -1.1

Trend of SO2S in the atmosphere -model versus observation (Košetice 1989-1996 )

Comparison model versus observation - SO4S concentration in the air (Košetice 1989-1996) y = 0.72x+1.32 Max. dif. = 59.4 Min. dif. = -26.5 RMSE = 3.3 BIAS = 0.7

Trend of SO4S in the atmosphere -model versus observation (Košetice 1989-1996 )

Comparison model versus observation - NO2N concentration in the air (Svratouch 1985-1996) y = 0.47x+1.14 Max. dif. = 16.3 Min. dif. = -19.3 RMSE = 2.4 BIAS = -0.1

Trend of NO2N in the atmosphere -model versus observation (Svratouch 1985-1996 )

Conclusions    ·       Concentrations of sulphur compounds have been declining steadily during the period reflecting a decrease in emissions regionally ·       Nitrogen dioxide concentrations dropped in 1980´s steadily, but no distinct change was observed during the nineties ·       The surface ozone concentrations at the regional scale of the Czech republic reach values that affect both human health and vegetation ·       The annual mean surface ozone concentration stabilised in the nineties at a relatively high level of around 70 μg.m-3. Since 1996 we have registered a slight decrease in annual means concentrations, but more importantly a reduction in the number of episodes in which ambient air pollution limit is exceeded ·       No significant trend was observed in mean annual concentrations of most VOCs in the period 1993-2001. Significant downward trend was found only by cyklohexane. Most of VOCs exhibit an annual cycle that reflect their emission level, i.e. with maxima in winter and minima in summer. Isoprene is an exception. Although ranking among the most reactive VOCs, it is of natural origin and displays an inverse pattern. ·       The reduction of sulphur emission in the Czech Republic has resulted in decreasing background sulphur deposition. The greatest difference is observed in throughfall, which means the decrease of dry sulphur deposition. ·       There is not considerable trend observed in the deposition of nitrogen ·       The deposition of hydrogen ions gradually goes down, pH of the precipitation samples increases. ·       In general, the highest deposition by all evaluated compounds was observed when the trajectories originate from northwestern direction

EExperience – problems       ·      We found a lot of discrepancies and problems in dataset during the process of data evaluation (2nd round of data checking) ·      Sampling method in precipitation quality monitoring was changed (before 1996 daily bulk – after 1996 weekly wet-only) – problems in evaluation ·      We found an error in the sector template tool in the process of data evaluation (corrected immediately)