Microwave Photonic Ultra-Wideband Radiometer For Planetary Boundary Layer Sensing

The Planetary Boundary Layer (PBL) is the portion of the troposphere that is directly influenced by the Earth's surface and responds to combined action of mechanical and thermal forcing. Most of the energy exchange with respect to solar heating and evaporation that drive the atmosphere and the ocean occur within the PBL, yet it is one of the most poorly observed and modeled regions of the atmosphere. Passive microwave instruments will be a critical component to a PBL observing system. Microwave passive instruments provide thermodynamic information in both cloudy and clear air, cloud and precipitation properties and surface flux information including temperature and wind speed. However, conventional passive microwave systems fall well short of being optimized for near surface sensing due to limited number of spectral channels and coarse spectral resolution covering only a small portion of the spectrum of interest for PBL sensing.