Volker Matthias GKSS Research Center Geesthacht Germany The

Volker Matthias, GKSS Research Center, Geesthacht, Germany The influence of MM 5 nudging schemes on CMAQ simulations of benzo(a)pyrene concentrations and depositions in Europe 1 Page 1

Outline § Introduction § MM 5 nudging schemes § Comparison to measurements § CMAQ model results for B(a)P and PM 10 § Conclusions Volker Matthias, GKSS Research Center, Geesthacht, Germany 2

Why PAHs ? PAHs imperil humans and ecosystems – highly bioaccumulative (food chain) – persistent in various environmental compartments – significant adverse effects already at low doses • carcinogenic B(a)P • impair immune system • impair reproduction Object of international reduction conventions (Target values for air concentrations EU: 1 ng/m 3 (annual average), UK: 0. 25 ng/m 3) Emissions are likely to increase Volker Matthias, GKSS Research Center, Geesthacht, Germany 3 wood burning, ship traffic

Model domains 54 x 54 km 2 grid 30 vertical layers up to 100 h. Pa 18 x 18 km 2 grid Volker Matthias, GKSS Research Center, Geesthacht, Germany 4

MM 5 parameterizations The use of MM 5 at GKSS: § Kain Fritsch 2 convective cloud scheme § MRF (Hong and Pan) PBL scheme § Reisner 2 microphysics scheme § Noah LSM § ERA 40 6 -hourly boundary conditions § (FDDA grid nudging with ERA 40 fields) Volker Matthias, GKSS Research Center, Geesthacht, Germany 5

Checking meteorological fields Comparison to ascents from 88 radiosonde station from the igra data base (Durre et al. , 2006). RS data is interpolated to model levels. Mean deviation and correlation are calculated for each profile. Volker Matthias, GKSS Research Center, Geesthacht, Germany 6

Test of nudging schemes Cases: • No nudging (no nudging) • No nudging, periodic restart (periodic) • Nudge only winds (nudge wind) • Nudge winds and temperature (nudge uvt) • Nudge winds, temperature and humidity (nudge all) • Nudge all, but use no LSM (nudge no LSM) • Nudge all with variable SST (nudge vsst) • Use subsets of layers (nudge all, 9 L (12 L)) Volker Matthias, GKSS Research Center, Geesthacht, Germany 7

Test of nudging schemes: temperature 5 3 0 -3 root mean square error / K nudge all periodic nudge wind no nudging nudge uvt nudge no LSM nudge vsst nudge all, 9 L (12 L) Volker Matthias, GKSS Research Center, Geesthacht, Germany 8 mean difference / K

Test of nudging schemes: rel. humidity 0. 4 0. 2 0 -0. 2 root mean square error nudge all periodic nudge wind no nudging nudge uvt nudge no LSM nudge vsst nudge all, 9 L (12 L) Volker Matthias, GKSS Research Center, Geesthacht, Germany 9 mean difference

Monthly mean of correlation and bias sorted by station: Rel. Humidity Year 2000, mean correlation (Rel. Hum. ) Volker Matthias, GKSS Research Center, Geesthacht, Germany 10

Annual mean of vertical wind profiles U-wind V-wind high temporal correlations at all heights (0. 85 - 0. 99) Volker Matthias, GKSS Research Center, Geesthacht, Germany 11

Comparison to wind-profiler data (CWINDE) mean vertical profiles (year 2000) Pendine/UK Data from Myles Turp, UK Met Office Volker Matthias, GKSS Research Center, Geesthacht, Germany 12 Lindenberg/D

U-wind spectra from wind profilers vs. model results Model/oberservations Model: influence of resolution and nudging Maximum-Entropy-spectra of the U-wind component Volker Matthias, GKSS Research Center, Geesthacht, Germany 13

Effects on B(a)P concentrations full nudging Volker Matthias, GKSS Research Center, Geesthacht, Germany 14 periodioc simulations

Effects on B(a)P depositions full nudging Volker Matthias, GKSS Research Center, Geesthacht, Germany 15 periodioc simulations

Annual PM 10 Time series of daily means at Neuglobsow/Germany, year 2000 mean bias -7. 4 mg/m 3 corr coeff 0. 52 Volker Matthias, GKSS Research Center, Geesthacht, Germany 16

Chemical composition at Melpitz/Germany Sec. Organic Aer. underestimated, particularly in summer Volker Matthias, GKSS Research Center, Geesthacht, Germany 17

PM 10 frequency distribution function Neuglobsow / Germany Payerne/Switzerland Frequency distribution of PM 10 measurements is log-normal. Model results reveal the same distribution function. Volker Matthias, GKSS Research Center, Geesthacht, Germany 18

Conclusions § MM 5 results were tested with different nudging schemes § Full nudging of T, RH, U and V permits close agreement with observations § Depending on horizontal grid scale, intraday variability of wind comp. is not resolved by the model § Deposition patterns can be highly sensitive to nudging/no nudging in MM 5 § PM 10 results imply significant underestimation of organic aerosol in summer § Good results for sec. inorganic aerosols in Central Europe Volker Matthias, GKSS Research Center, Geesthacht, Germany 19