Clear-Air Backscatter from the Lower Atmosphere Using a High-Power, Millimeter Wave Radar

This paper presents our clear-air backscattering observations from the lower atmosphere using the high power, high resolution WARLOC millimeter wave (94 GHz) radar developed at the Naval Research Laboratory (NRL) [1]. With a peak power of 70 kW and a 62-dB gain antenna, the WARLOC radar offers more than 30 dB higher sensitivity than typical weather radars at this frequency. In addition, the radar provides unprecedented high range and spatial resolution with the 50-cm range resolution and a beam width of less than 0.1 degrees, respectively. The radar is currently located at the NRL's Chesapeake Bay Detachment (CBD) facility, on the western shore of the Chesapeake Bay, Maryland, providing observations eastward across the bay. The unique capabilities of the WARLOC radar have opened up new opportunities in atmospheric research. In this paper, characteristics of clear-air backscatter will be presented. Radar cross sections as a function of temperature and height will be discussed. These observations will be related to phenomena such as clear-air turbulence and convective eddies.