Development and Evaluation of satellite ValidatiOn Tools by Experimenters

The Polarized Imaging Nephelometer is an in situ instrument designed and built at the Laboratory for Aerosols, Clouds and Optics (LACO) at the University of Maryland Baltimore County for the measurement of components of the aerosol phase matrix in high angular resolution between 2 to 178 deg scattering angles. The measured phase matrix provides extensive characterization of the scattering properties of the studied aerosols allowing for a very comprehensive set of aerosol scattering parameters. These measurements are essential for the validation of the new generation of aerosol remote sensors like the APS polarimeter in the Glory satellite, and for the construction of accurate models of real aerosol particles, specially the non-spherical ones.

The Langley Aerosol Research Group Experiment (LARGE) is an in situ airborne instrument suite that measures aerosol and cloud microphysical and optical properties such as size distribution, number concentration, and scattering and absorption coefficient. LARGE consists of multiple instruments including the Ultra-High Sensitivity Aerosol Spectrometer (UHSAS), Particle-Into-Liquid Sampler (PILS), Particle Soot Absorption Photometer (PSAP), Cloud and Aerosol Spectrometer (CAS), Cloud Imaging Probe (CIP), and additional cloud and aerosol sensors. The LARGE instruments operate across the 450-700 nm wavelength range, can detect particles in the size range between 0.003-20μm, and have a measurement frequency of 1 Hz. It is typically used for airborne measurements, but it also can be deployed on ground-based platforms such as vehicles.

The Diode Laser Hygrometer (DLH) is an in situ airborne hygrometer developed by NASA’s Langley Research Center (LaRC). It uses tunable diode laser absorption to measure water vapor in the atmosphere. DLH operates in the near-infrared region at around 1.4 μm and has a measurement frequency of 100 Hz. It can provide accurate measurements of water vapor even while flying through clouds.