Characterizing dust aerosols with lidar and UAV based measurements (Cyprus Fall campaign 2021)

Due to its geographical location, Cyprus is often affected by dust storms arriving from the largest
deserts of the planet, the Sahara, the Arabian Peninsula and the Syrian. In order to characterize dust
properties, the Cyprus Atmospheric Observatory (CAO) and the Unmanned Research Laboratory
(USRL) of the Cyprus Institute (CYI), in collaboration with the Cyprus Atmospheric Remote sensing
Observatory (CARO) of the ERATOSTHENES Centre of Excellence (ECoE) of the Cyprus University of
Technology (CUT), performed a research campaign in Fall 2021. Measurements were performed with
ground-based aerosol remote sensing systems (lidars, ceilometers and sunphotometers), and UAV
based in-situ instruments (OPCs, backscatter sondes, and impactors able to collect dust samples). As
part of the remote sensing observations, two depolarized lidars performed measurements from
different locations, one from CYI premises in Nicosia and the second one from ECoE-CUT premises in
Limassol. The lidar signals provide information about the vertical aerosol profile at the two locations,
which can be used to derive the optical properties of dust at different altitudes. Here, we will
present first results on the synergy between the continuous vertically extended measurements of
lidars and the in-situ measurements from UAV instrumentation during the periods of dust outbreaks.
The two events occurred from 25 October to 1 November and from 13 to 18 November 2021. During
these dust events, the lidars observed depolarized aerosol layers from ground up to 5 km above sea
level. The lidar measurements provided the temporal and spatial development of these dust layers,
and were also used in real-time for planning the UAV flight schedule. According to backward
trajectory analyses, the two dust events had different origins with the first arriving from the Sahara
and the second one from the Middle East.