Extinction-related Angström exponent characterization of submicrometric volume fraction in atmospheric aerosol particles Quirantes, A. Guerrero Rascado, Juan Luis Pérez Ramírez, Daniel Foyo Moreno, Inmaculada Ortiz-Amezcua, Pablo Benavent Oltra, José Antonio Lyamani, H. Titos Vela, Gloria Bravo Aranda, Juan Antonio Cazorla, A. Valenzuela, A. Casquero Vera, Juan Andrés Bedoya-Velásquez, Andrés Esteban Alados Arboledas, Lucas Olmo Reyes, Francisco José Lidar Aerosol Graphical method Submicrometric fraction The AEAOD– ΔAEAOD grid proposed by Gobbi et al. (2007) is a graphical method used to visually represent the spectral characterization of aerosol optical depth (AOD), i.e. Angström exponent (AE) and its curvature, in order to infer the fine mode contribution (η) to the total AOD and the size of the fine mode aerosol particles. Perrone et al. (2014) applied this method for the wavelengths widely used in lidar measurements. However, in neither case does the method allow for a direct relationship between η and the fine mode fraction contribution to the total aerosol population. Some discussions are made regarding the effect of shape and composition to the classical AE-ΔAE plot. The potential use of particle backscatter measurements, widely used in aerosol characterization methods together with extinction measurements, is also discussed in the AE-ΔAE grid context. A modification is proposed that yields the submicron contribution to the total volume concentration by using particle extinction data, and a comparison to experimental measurements is made. Our results indicate that the use of a modified AE-ΔAE grid plot to directly obtain submicrometric and micrometric mode fraction to the total aerosol population is feasible if a volume-based bimodal particle size distribution is used instead of a number-based one. 2019-07-01T11:10:16Z 2019-07-01T11:10:16Z 2019 info:eu-repo/semantics/article http://hdl.handle.net/10481/56240 https://doi.org/10.1016/j.atmosres.2019.06.009 eng 228; European Union's Horizon 2020 research and innovation program under grant agreement n. 654169 info:eu-repo/semantics/openAccess Elsevier