Publication Date:
2020-12-22
Description:
During the ADRIMED (Aerosol Direct Radiative
Impact on the regional climate in the Mediterranean region)
special observation period (SOP-1a), conducted in June 2013
in the framework of the ChArMEx (Chemistry-Aerosol
Mediterranean Experiment) project, a moderate Saharan dust
event swept the Western and Central Mediterranean Basin
(WCMB) from west to east during a 9-day period between
16 and 24 June. This event was monitored from the ground
by six EARLINET/ACTRIS (European Aerosol Research
Lidar Network/Aerosols, Clouds, and Trace gases Research
Infrastructure Network) lidar stations (Granada, Barcelona,
Naples, Potenza, Lecce and Serra la Nave) and twoADRIMED/ChArMEx lidar stations specially deployed for
the field campaign in Cap d’en Font and Ersa, in Minorca and
Corsica Islands, respectively. The first part of the study shows the
spatio-temporal monitoring of the dust event during its transport
over the WCMB with ground-based lidar and co-located
AERONET (Aerosol Robotic Network) Sun-photometer measurements.
Dust layer optical depths, Ångström exponents,
coarse mode fractions, linear particle depolarization ratios
(LPDRs), dust layer heights and the dust radiative forcing estimated
in the shortwave (SW) and longwave (LW) spectral ranges
at the bottom of the atmosphere (BOA) and at the top of the
atmosphere (TOA) with the Global Atmospheric Model
(GAME), have been used to characterize the dust event. Peak
values of the AERONETaerosol optical depth (AOD) at 440 nm
ranged between 0.16 in Potenza and 0.37 in Cap d’en Font. The
associated Ångström exponent and coarse mode fraction mean
values ranged from 0.43 to 1.26 and from 0.25 to 0.51, respectively.
The mineral dust produced a negative SWdirect radiative
forcing at the BOA ranging from −56.9 to −3.5Wm−2. TheLW
radiative forcing at the BOAwas positive, ranging between +0.3
and +17.7 W m-2. The BOA radiative forcing estimates agree
with the ones reported in the literature. At the TOA, the SW
forcing varied between −34.5 and +7.5 W m−2. In seven cases,
the forcing at the TOA resulted positive because of the aerosol
strong absorbing properties (0.83 〈 single-scattering albedo
(SSA) 〈 0.96). The multi-intrusion aspect of the event is examined
by means of air- and space-borne lidar measurements, satellite
images and back trajectories. The analysis reported in this
paper underline the arrival of a second different intrusion of
mineral dust observed over southern Italy at the end of the considered
period which probably results in the observed heterogeneity
in the dust properties.
Description:
Published
Description:
261–285
Description:
7A. Geofisica per il monitoraggio ambientale e geologia medica
Description:
JCR Journal
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
Permalink
