Comparisons of the Micropulse Lidar and the Belfort Laser Ceilometer at the Atmospheric Radiation Measurement Southern Great Plains Cloud and Radiation Testbed Site

The general goal of the Atmospheric Radiation Measurement (ARM) Program is to improve general circulation and related models of the atmosphere for global and regional prediction (DOE 1990). In order to achieve this goal, the ARM Program is collecting a prodigious volume of data at its first Cloud and The time period selected to do the comparisons between the Radiation Testbed (CART) in the Southern Great Plains of the instruments was April 4, 1994, through May 8, 1994. In this United States. Some quantities, such as cloud base height, can window, there were 36,920 MPL samples, of which 13,935 be measured by a variety of different means. The ARM were indicated as clear, 20,262 were indicated as cloudy, and Program currently has two active systems that provide 2,723 were indicated as foggy. Since the BLC has a measurements of the cloud base height, the Micropulse Lidar maximum range of 7800 meters, the MPL cloudy cases were and the Belfort Laser Ceilometer. This paper provides an divided into two groups, those above and below 7800 meters. initial comparison of these two instruments. The former were removed from the analysis. Thus there were