PNNL

Abstract

Atmospheric radiative forcing, surface radiation budget, and top of the atmosphere radiance interpretation involve knowledge of the vertical height structure of overlying cloud and aerosol layers. During the last decade, the U.S. Department of Energy through the Atmospheric Radiation Measurement (ARM) program, has constructed four long-term atmospheric observing sites in strategic climate regimes (north central Oklahoma, Barrow, Alaska, and Nauru and Manus Islands in the tropical western Pacific). Micro Pulse Lidar (MPL) systems provide continuous, autonomous observation of nearly all significant atmospheric cloud and aerosol at each of the central ARM facilities. Systems are compact and transmitted pulses are eye-safe. Eye-safety is achieved by expanding relatively low-powered outgoing pulse energy through a shared, coaxial transmit/receive telescope. ARM MPL system specifications, and specific unit optical designs are discussed. Data normalization and calibration techniques are presented. These techniques in tandem represent an operational value added processing package used to produce normalized data products for ARM cloud and aerosol research.