The natural emissions model (NEMO): Description, application and model evaluation

Abstract

The aim of this study is the application and evaluation of a new computer model used for the quantification of emissions coming from natural sources. The Natural Emissions Model (NEMO) is driven by the meteorological data of the mesoscale numerical Weather Research and Forecasting (WRF) model and it estimates particulate matter (PM) emissions from windblown dust, sea salt aerosols (SSA) and primary biological aerosol particles (PBAPs). It also includes emissions from Biogenic Volatile Organic Compounds (BVOCs) from vegetation; however, this study focuses only on particle emissions. An application and evaluation of NEMO at European scale are presented. NEMO and the modelling system consisted of WRF model and the Comprehensive Air Quality Model with extensions (CAMx) were applied in a 30 km European domain for the year 2009. The computed domain-wide annual PM10 emissions from windblown dust, sea salt and PBAPs were 0.57 Tg, 20 Tg and 0.12 Tg, respectively. PM2.5 represented 6% and 33% of emitted windblown dust and sea salt, respectively. Natural emissions are characterized by high geographical and seasonal variations; windblown dust emissions were the highest during summer in the southern Europe and SSA production was the highest in Atlantic Ocean during the cold season while in Mediterranean Sea the highest SSA emissions were found over the Aegean Sea during summer. Modelled concentrations were compared with surface station measurements and showed that the model captured fairly well the contribution of the natural sources to PM levels over Europe. Dust concentrations correlated better when dust transport events from Sahara desert were absent while the simulation of sea salt episodes led to an improvement of model performance during the cold season.

Publication
Atmospheric Environment 122:493-504
Date
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