Measurements of Aerosol Size and Microphysical Properties: A Comparison Between Raman Lidar and Airborne Sensors

Abstract

This manuscript compares measurements of aerosol size distributions and microphysical properties retrieved from the Raman lidar BASIL with those obtained from a series of aircraft sensors during HyMeX‐SOP1. The attention is focused on a measurement session on 02 October 2012, with BASIL measurements revealing the presence of a lower aerosol layer extending up to 3.3 km and an elevated layer extending from 3.6 to 4.6 km. Aerosol size distribution and microphysical properties are determined from multi‐wavelength particle backscattering and extinction profile measurements through a retrieval approach based on Tikhonov regularization. A good agreement is found between BASIL and the microphysical sensors' measurements for all considered aerosol size and microphysical properties. Specifically, BASIL and in‐situ volume concentration values are in the range 2–5 μm3 cm−3 in the lower layer and in the range 1–3.5 μm3 cm−3 in the upper layer. Values of the effective radius values from BASIL and the in‐situ sensors are in the range 0.2–0.6 μm in both the lower and upper layer. Aerosol size distributions are determined at 2.2, 2.8, 4 and 4.3 km, with a good agreement between the Raman lidar and the microphysical sensors at all considered heights. We combined these size and microphysical results with Lagrangian back‐trajectory analyses and chemical composition measurements. From this combination of datasets we conclude that aerosol particles below 3 km were probably originated by wildfires in North America and/or by anthropogenic activities in North‐Eastern Europe, while aerosols above 3 km were also probably originated by wildfires in North America.

Understanding Aerosol-Cloud Interactions Through Lidar Techniques: A Review

“…inversions of spectral measurements of sky radiance and atmospheric transmittance from sunphotometers) or colocated in-situ data. [91][92][93][94][95][96]…”

Assessing Lidar Ratio Impact on CALIPSO Retrievals Utilized for the Estimation of Aerosol SW Radiative Effects across North Africa, the Middle East, and Europe

“…Ground-based measurements, acquired using instrumentations deploying passive or active remote sensing techniques, have provided critical insight on aerosol-speciated intensive and extensive radiative properties [18][19][20][21][22][23]. Spaceborne observations, providing near-global coverage, have effectively overcome the spatial constraints of ground-based stations [24][25][26][27][28][29][30]. Passive sensors, such as the MODerate resolution Imaging Spectroradiometer (MODIS), onboard Terra, and Aqua satellites, have supplied the scientific community with multi-year records of the columnar aerosol optical depth (AOD) since 2000 [31][32][33][34][35].…”

Atmospheric Boundary Layer Height: Inter-Comparison of Different Estimation Approaches Using the Raman Lidar as Benchmark

“…One approach is based on the computation of the derivative of the elastic lidar backscatter signal [6][7][8][9][10]; alternative approaches consider the elastic backscatter lidar signal variance or a threshold signal level [11][12][13][14][15][16][17]. Another effective approach to estimate the ABLH relies on the application of a Haar wavelet covariance transform to elastic backscatter lidar signals [18][19][20]. However, the application of the above-mentioned methodologies to the elastic backscatter lidar signals may produce false ABLH estimates in the presence of advection and local accumulation processes.…”