Urmia Lake (UL) in the northwest of Iran is a salt-saturated lake. In September 2018, a station equipped with LiDAR was installed next to the UL. A scanning polarization LiDAR was used to study suspended particles in the UL atmosphere. IASBS Scanning Polarization LiDAR, ISPL located on the west coast of UL. Measurement at ISPL station started (ended) in October 2018 (November 2020). At this time, 55 (133) days were recorded at horizontal scanning (zenith direction). Measurement of horizontal scanning was done in mild weather. When there is temperature reduction, strong winds, and rain, it is not possible. Quality of data and resolution were better during the nighttime than during the daytime. Horizontal scanning from the UL atmosphere shows particles with a 10% until 20% volume depolarization ratio (VDR) were in the atmosphere in October 2018. VDR of these particles is very close to dry salt particles' depolarization ratio. Particles with this feature were observed at low altitudes (near to the ground) with short lifetimes. Surface wind speed and direction are an important reason for the displacement of them. When the season of raining start, these particles did not exist in the atmosphere. Atmospheric humidity affects the particle depolarization ratio. In the zenith direction, data recording was performed in different weather conditions. Measurement on cold days (in 2018 and 2019) shows the lake atmosphere is less affected by the UL dry bed. Particles with 10-20% VDR were observed at the lowest altitude of 2 km, with a short lifetime. But Measurement in the zenith direction in the summer of 2020 shows particles with ∼15% VDR observed at upper altitude (2-4 km). The back trajectory of some of them was from local sources (UL dry bed and lands around it). During the summer, the UL dry bed can be a local source of atmospheric particles. Salt particles, scanning polarization LiDAR, Urmia Lake.
Urmia
Lake
(UL) in the northwest of Iran is a salt-saturated
lake
. In September 2018, a station equipped with
LiDAR
was installed
next
to the UL. A
scanning
polarization
LiDAR
was
used
to study suspended
particles
in the UL
atmosphere
.
IASBS
Scanning
Polarization
LiDAR
,
ISPL
located on the west coast of UL.
Measurement
at
ISPL
station
started
(ended) in October 2018 (November 2020). At this time, 55 (133) days
were recorded
at horizontal
scanning
(zenith
direction)
.
Measurement
of horizontal
scanning
was done
in mild weather. When there is temperature reduction, strong winds, and rain, it is not possible. Quality of data and resolution were better during the nighttime than during the daytime. Horizontal
scanning
from the UL
atmosphere
shows
particles
with a 10% until 20% volume depolarization ratio (
VDR
) were in the
atmosphere
in October 2018.
VDR
of these
particles
is
very
close to
dry
salt particles' depolarization ratio.
Particles
with this feature
were observed
at low altitudes (near to the ground) with short lifetimes. Surface wind speed and
direction
are an
important
reason for the displacement of them. When the season of raining
start
, these
particles
did not exist in the
atmosphere
. Atmospheric humidity affects the
particle
depolarization ratio. In the zenith
direction
, data recording
was performed
in
different
weather conditions.
Measurement
on
cold
days (in 2018 and 2019)
shows
the
lake
atmosphere
is less
affected
by the UL
dry
bed.
Particles
with 10-20%
VDR
were observed
at the lowest altitude of 2 km, with a short lifetime.
But
Measurement
in the zenith
direction
in the summer of 2020
shows
particles
with ∼15%
VDR
observed at upper altitude (2-4 km). The back trajectory of
some
of them was from local sources (UL
dry
bed and lands around it). During the summer, the UL
dry
bed can be a local source of atmospheric
particles
. Salt
particles
,
scanning
polarization
LiDAR
,
Urmia
Lake
.