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Measurements from the South Dakota School of Mines and Technology T-28 hail-penetrating aircraft are analyzed using recently developed data processing techniques with the goals of identifying where the large hail is found relative to vertical motion and improving the detection of hail microphysical properties from radar. Hail particle size distributions (PSD) and environmental conditions (temperature, relative humidity, liquid water content, air vertical velocity) were digitally collected by the T28 between 1995 and 2003 and synthesized by Detwiler et al. The PSD were forward modeled by Cecchini et al. to simulate the radar reflectivity of the PSD at multiple radar wavelengths. The T-28 penetrated temperatures primarily between 08 and 2108C. The largest hailstones were sampled near the updraft/downdraft interface. Liquid water contents were highest in the updraft cores, whereas total (liquid 1 frozen) water contents were highest near the updraft/downdraft interface. The fitted properties of the PSD (intercept and slope) are directly related to each other but do not show any dependence on the region of the hailstorm where sampled. The PSD measurements and the radar reflectivity calculations at multiple radar wavelengths facilitated the development of relationships between the PSD bulk properties-hail kinetic energy and kinetic energy flux-and the radar reflectivity. Rather than using the oft-assumed sphericity and solid ice physical properties, actual measurements of hail properties are used in the analysis. Results from the maximum estimated size of hail (MESH) and vertical integrated liquid water (VIL) algorithms are evaluated based on this analysis. SIGNIFICANCE STATEMENT: Hailstorms in the United States have caused over $10 billion in damage for each of the last 14 years, according to insurance industry estimates (Heymsfield and Giammanco 2020). Algorithms have been developed to identify the presence and size of hail from radar. Numerical simulations of hailstorms have improved significantly since the 1970s, and further improvements will provide better resolution and more accurate estimates of the sizes of hailstones falling to the ground. Measurements of the properties of hailstones-their mass and terminal velocities-have been improved in recent years but in general are not incorporated in the algorithms developed for radar estimates of hail sizes or for the properties of hail used in the model simulations. This study synthesizes in situ aircraft data, computed radar backscatter cross sections, together with recent estimates of the physical characteristics of hailstones to improve the representation of hail in numerical models and quantitative assessment hail properties in storms using weather radar. [ABSTRACT FROM AUTHOR]

The lowest bandgap, soluble, spray-processable polymer is produced by combining a strong donor, tris(dodecyloxy)phenyl)-dithieno[3,2-b:2',3'-d-pyrrole, with a strong acceptor, 4,8-dithien-2-yl-2[[lambda].sup.4][[delta].sup.2]-benzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole. Transmission/absorption spectroscopy on single-walled carbon nanotubes (SWCNTs) and reflectance spectroscopy on gold are used for estimating the optical bandgap.

Exploitation of millimetre-wave radiometer and radar observations of ice clouds and snow requires the ability to model the scattering properties of snowflakes. This article extends the Self-Similar Rayleigh-Gans Approximation (SSRGA) for rapid computation of the backscatter cross-section of ice aggregates, to compute the full scattering phase function, the scattering and absorption cross-sections and the asymmetry factor. We also show that the Rayleigh-Gans Approximation (RGA) may be improved to represent the enhanced scattering and absorption when the monomers from which the aggregate is composed are non-spherical. The new model is shown to perform well when compared to benchmark 94 and 183 GHz Discrete Dipole Approximation (DDA) calculations of the scattering by simulated unrimed aggregates of maximum dimension up to 1 cm that have a mass-size relationship in the range observed from aircraft. For denser particles, such as would result from riming, the validity of the underlying RGA becomes questionable and both the backscatter and scattering cross-sections can be underestimated by a factor of 2. [ABSTRACT FROM AUTHOR]