Assessment of Aerosol-Radiation (ARI) and Aerosol-Cloud (ACI) Interactions from Dust: Modelled Dust Optical Properties and Remote Sensing Observations

Abstract

Dust is a natural aerosol with an important influence over the Mediterranean basin from a climatic perspective. WRF-Chem simulations have been evaluated over Europe for an October 2010 dust episode. Three modeling scenarios differ in the inclusion or not of aerosol-radiation-cloud interactions.The evaluation of the aerosol optical depth (AOD) indicates a slight improvement of simulations when evaluated against MODIS when including the aerosol radiative feedbacks (RF). For the and Angström exponent (AE), the model tends to underestimate the variability of this variable, and a much more limited improvement when including RF.

Questions and Answers

Questioner: Pavel Kisheha

Question: MODIS AOD includes contributions not only from mineral dust but also from other aerosol species such as sea salt, industrial pollution, ship emissions, etc. Could it be that the model underestimation of MODIS AOD could be explained by the contribution of non-dust aerosol instead of radiation effects of dust?

Answer: Non-dust aerosol species are included in the model. Anthropogenic emissions, as industrial pollution, are obtained from a recent update of the TNO MACC emissions inventory (http://www.gmes-atmosphere.eu/; Pouliot et al. 2012, 2015; Kuenen et al. 2014). Biomass burning emission, such as black carbon have been calculated from global fire emission data that have been supplied from the integrated monitoring and modelling system for wild-land fires (IS4FIRES) project (Sofiev et al. 2009) with 0.1$\,\times \,0.1^{\circ }$ spatial resolution. Biogenic emissions are based on the Model of Emissions of Gases and Aerosols from Nature (MEGAN) model (Guenther 2006) which is on-line coupled with WRF-Chem and makes use of simulated temperature and solar radiation. Moreover, dust and sea salt emissions are estimated online by WRF-Chem from the meteorological parameters.