Current Science

Ajay Kumar Patel ¹, Bhavani Kumar Yellapragada ¹, R. Vishnu ², M. V. R. Murti ¹, James Jebaseelan Samuel ³

Affiliations
1 Centre of Studies in Resources Engineering, Indian Institute of Technology-Bombay, Powai, Mumbai 400 076, IN
2 National Atmospheric Research Laboratory, Department of Space, Government of India, Gadanki 517 112, IN
3 Photonics, Nuclear and Medical Physics Division, VIT University, Vellore 632 014, IN

Abstract

We describe an indigenously developed dual polarization lidar (DPL) system for remote sensing of the range resolved properties of non-spherical nature of air borne and cloud particles. The DPL system probes the atmosphere using a linearly polarized second harmoni cNd : YAG laser. The design of receiver optics is such that it separates the collected back scattered light into parallel and perpendicular polarization components.The ratio of intensity of perpendicular to parallel signals is known as the depolarization ratio (DR), which is a gauge for non-spherical particle content in the atmosphere. The DPL employs an external irradiance standard to calibrate the depolarization measurements.Comparison of simultaneous measurements between DPL and a similar instrument validates the utility of the system for cloud and aerosol studies. The altitude profiles of DR derived from lidar signals potentially indicate the type of major particle layers in the atmosphere.

Keywords

Aerosols, Clouds, Laser, Polarization Lidar, Remote Sensing.

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