Modelling the Impact of Sub-grid Scale Emission Variability on Upper-air Concentration

The long standing issue of sub-grid emission heterogeneity and its influence to upper air concentration is addressed here and a subgrid model proposed. The founding concept of the approach is the assumption that average emission act as source terms of average concentration, emission fluctuations are source for the concentration variance. The model is based on the derivation of the sub-grid contribution of emission and the use of the concentration variance equation to transport it in the atmospheric boundary layer. The model has been implemented in an existing mesoscale model and the results compared with Large-Eddy Simulation data for ad-hoc simulation devised to test specifically the parametrization. The results show an excellent agreement of the models. For the first time a time evolving bar reproducing the sub-grid scale heterogeneity of the emissions and the way in which it affects the concentration been shown. The concentration variance is presented as extra attribute to better define the mean concentrations Reynolds-average model. The model has applicationsmeso to global scale and that go beyond air quality.

GALMARINI Stefano;  VINUESA Jean;  MARTILLI Alberto; 

2008-04-30

EUROPEAN GEOSCIENCES UNION

JRC43039

1680-7324,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC43039,