Abstract. A stand-alone lidar-based method for detecting airborne hazards for
aviation in near real time (NRT) is presented. A polarization lidar
allows for the identification of irregular-shaped particles such as
volcanic dust and desert dust. The Single Calculus Chain (SCC) of the
European Aerosol Research Lidar Network (EARLINET) delivers high-resolution
preprocessed data: the calibrated total attenuated backscatter and
the calibrated volume linear depolarization ratio time series. From
these calibrated lidar signals, the particle backscatter coefficient
and the particle depolarization ratio can be derived in temporally
high resolution and thus provide the basis of the NRT early warning
system (EWS). In particular, an iterative method for the retrieval of
the particle backscatter is implemented. This improved capability was
designed as a pilot that will produce alerts for imminent threats for
aviation. The method is applied to data during two diverse aerosol
scenarios: first, a record breaking desert dust intrusion in March 2018 over Finokalia, Greece, and, second, an intrusion of volcanic
particles originating from Mount Etna, Italy, in June 2019 over Antikythera,
Greece. Additionally, a devoted observational period including several
EARLINET lidar systems demonstrates the network's preparedness to
offer insight into natural hazards that affect the aviation sector.