Intense Saharan Dust Outbreak over the Iberian Peninsula in springtime 2021: Monitoring and Characterization of Transported Dust Particles

Abstract

In spring 2021 an intense Saharan dust outbreak reached the Iberian Peninsula (IP), lasting from 26 March until 5 April. It was monitored at six lidar stations, belonging to either MPLNET or ACTRIS/EARLINET networks, covering thus almost all the IP extension. Polarized Micro-Pulse Lidar measurements were carried out at El Arenosillo/Huelva (ARN, Spain; 37.1ºN, 6.7ºW, 40 m a.s.l.), Torrejón de Ardoz (TRJ, Spain; 40.5º N, 3.5º W, 568 m a.s.l, which is not within MPLNET yet), and Barcelona (BCN, Spain; 41.4ºN, 2.1ºE, 125 m a.s.l.); and multi-wavelength Raman lidars measurements were performed at Granada (GRA, Spain; 37.1ºN, 3.6ºW, 680 m a.s.l.), Évora (EVO, Portugal; 38.6ºN, 7.9º W, 293 m a.s.l.), and Madrid (MAD, Spain; 40.5ºN, 3.7ºW, 680 m a.s.l.). Both particle backscatter coefficient (βp) and particle linear depolarization ratio (δp) profiles are retrieved for all the stations under cloud-free conditions. The optical properties (backscatter and extinction coefficients at 532 nm) for both the fine (Df) and coarse (Dc) dust components are separately derived by applying the POLIPHON (POlarisation LIdar PHOtometer Networking; Mamouri and Ansmann, 2014) approach. Additionally, the mass concentration profiles, the mass extinction efficiency and the height of the centre-of-mass for both fine and coarse-modes are also calculated for the overall period. Results are compared along with the evolution of the dust intrusion as it crosses the IP.