Aerosol optical depth derived from lidar measurements during VELETA-2002 campaign

This study shows a set of analysis of measurements from ground-based and satellite instruments to characterize the twilight zone (TLZ) between clouds and aerosols in São Paulo, Brazil. In the vicinity of clouds turbulence measurements showed an intense upward movement of aerosol layers, while sunphotometer results showed an increase in aerosol optical depth, and lidar measurements showed an increase in the backscatter vertical profile signal.

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The potential of elastic and polarization lidars to retrieve extinction profiles

Atmospheric Measurement Techniques ◽

10.5194/amt-13-893-2020 ◽

2020 ◽

Vol 13 (2) ◽

pp. 893-905 ◽

Cited By ~ 5

Author(s):

Elina Giannakaki ◽

Panos Kokkalis ◽

Eleni Marinou ◽

Nikolaos S. Bartsotas ◽

Vassilis Amiridis ◽

...

Keyword(s):

Aerosol Optical Depth ◽

Optical Depth ◽

Dust Particles ◽

Depolarization Ratio ◽

Lidar System ◽

Lidar Measurements ◽

Lidar Ratio ◽

Linear Depolarization Ratio ◽

Aerosol Types ◽

532 Nm

Abstract. A new method, called ElEx (elastic extinction), is proposed for the estimation of extinction coefficient lidar profiles using only the information provided by the elastic and polarization channels of a lidar system. The method is applicable to lidar measurements both during daytime and nighttime under well-defined aerosol mixtures. ElEx uses the particle backscatter profiles at 532 nm and the vertically resolved particle linear depolarization ratio measurements at the same wavelength. The particle linear depolarization ratio and the lidar ratio values of pure aerosol types are also taken from literature. The total extinction profile is then estimated and compared well with Raman retrievals. In this study, ElEx was applied in an aerosol mixture of marine and dust particles at Finokalia station during the CHARADMExp campaign. Any difference between ElEx and Raman extinction profiles indicates that the nondust component could be probably attributed to polluted marine or polluted continental aerosols. Comparison with sun photometer aerosol optical depth observations is performed as well during daytime. Differences in the total aerosol optical depth are varying between 1.2 % and 72 %, and these differences are attributed to the limited ability of the lidar to correctly represent the aerosol optical properties in the near range due to the overlap problem.

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Lidar Measurements for Comparison of Atmospheric Aerosol Extinction and Scattering Properties over Lanzhou, China

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.137.256 ◽

2011 ◽

Vol 137 ◽

pp. 256-261 ◽

Cited By ~ 1

Author(s):

Xian Jie Cao ◽

Lei Zhang ◽

Xiao Jing Quan ◽

Bi Zhou ◽

Jing Bao ◽

...

Keyword(s):

Aerosol Optical Depth ◽

Optical Depth ◽

Extinction Coefficient ◽

Atmospheric Aerosol ◽

Aerosol Extinction ◽

Vertical Profiles ◽

Lidar Measurements ◽

The Difference ◽

Aerosol Extinction Coefficient ◽

Semi Arid

The aerosol comparison experiment was conducted in the Semi-Arid Climate and Environment Observatory of Lanzhou University since March to April 2007 with the measurements of two micro-pulse lidars MPL-4B and CE370-2. In the paper, the differences of aerosol extinction coefficient and optical depth retrieved from the observations of MPL-4B and CE370-2 are analyzed, and the results show: the aerosol extinction coefficient retrieved from the observation of MPL-4B is in general smaller than that from CE370-2, and the difference mainly exists in the low layer, while their trends of vertical profiles agree well; the aerosol optical depths from the observations of MPL-4B and CE370-2 correlate linearly rather well with the coefficient of 0.71, and the aerosol optical depth retrieved from the measurement of MPL-4B is less than that from CE370-2 in whole.

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Retrieval of the Pinatubo-Aerosol Optical Depth and Microphysical Parameters from Lidar Measurements.

The Review of Laser Engineering ◽

10.2184/lsj.23.154 ◽

1995 ◽

Vol 23 (2) ◽

pp. 154-160 ◽

Cited By ~ 3

Author(s):

Albert ANSMANN ◽

Horst JAGER

Keyword(s):

Aerosol Optical Depth ◽

Optical Depth ◽

Microphysical Parameters ◽

Lidar Measurements

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A Study of Air Quality in the Southeastern Hampton–Norfolk–Virginia Beach Region with Airborne Lidar Measurements and MODIS Aerosol Optical Depth Retrievals

Journal of Applied Meteorology and Climatology ◽

10.1175/2009jamc2119.1 ◽

2010 ◽

Vol 49 (1) ◽

pp. 3-19 ◽

Cited By ~ 5

Author(s):

Jasper Lewis ◽

Russell De Young ◽

D. Allen Chu

Keyword(s):

Air Quality ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Airborne Lidar ◽

Eastern United States ◽

Modis Aod ◽

Virginia Beach ◽

Lidar Measurements ◽

Langley Research Center ◽

Linear Regressions

Abstract A study of air quality was performed using a compact, aircraft aerosol lidar designed in the Science Directorate at NASA Langley Research Center and Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD) retrievals. Five flights of lidar measurements conducted in the Hampton–Norfolk–Virginia Beach, Virginia, region showed complex regional aerosol distributions. Comparisons with MODIS AOD at 10 km × 10 km and 5 km × 5 km resolutions show good agreement, with correlation R2 values of 0.82 and 0.88, respectively. Linear regressions of particulate matter with a diameter of less than 2.5 μm (PM2.5) and AOD within the ranges of 5–40 μg m−3 and 0.05–0.7, respectively, result in R2 values of ∼0.64 and ∼0.82 for MODIS and the Compact Aerosol Lidar, respectively. The linear regressions reflect approximately 51 μg m−3 to 1 AOD. These relationships are in agreement with previous findings for air pollution aerosols in the eastern United States and in northern Italy. However, large vertical variation is seen case by case, with planetary boundary layer heights ranging between 0.7 and 2 km and uncertainties ranging between 0.1 and 0.4 km. The results of the case studies suggest that AOD can be used as an indicator of surface measurements of PM2.5 but with larger uncertainties associated with small aerosol loading (AOD < 0.3).

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