[1] This paper presents an empirical method for converting reflectivity from Ku-band (13.8GHz) to S-band (2.8GHz) for several hydrometeor species, which facilitates the incorporation of Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) measurements into quantitative precipitation estimation (QPE) products from the U.S. Next-Generation Radar (NEXRAD). The development of empiric...

∗ Authors are with the Department of Atmospheric Science, University of Wyoming., Laramie, WY 82071. Email: [email protected] and [email protected]. Abstract: Measurements of backscattered power were made in maritime stratus with a 95 GHz pulsed radar mounted on an aircraft. The aircraft also carried probes for the in situ characterization of the cloud composition in terms of liquid water content (LW...

Observations show that on a mountainside the boundary between snow and rain, the snow line, is often located at an elevation hundreds of meters below its elevation in the free air upwind. The processes responsible for this mesoscale lowering of the snow line are examined in semi-idealized simulations with a mesoscale numerical model and in simpler theoretical models. Spatial variations in laten...

The processes that fix the fractionation of the stable isotopologues of water in the tropical tropopause layer (TTL) are studied using cloud-resolving model simulations of an idealized equatorial Walker circulation with an imposed Brewer-Dobson circulation. This simulation framework allows the explicit representation of the convective and microphysical processes at work in the TTL. In this mode...

Terrestrial Free-space optical communication (FSO) links have yet to achieve a mass market success due to the ever elusive 99.999% availability requirement. The terrestrial FSO links are heavily affected by atmospheric fog. To design systems which can achieve high availability and reliability in the presence of fog, accurate and better models of fog attenuation need to be developed. The current...

Use of dual-wavelength radar, with properly chosen wavelengths, will significantly lessen the ambiguities in the retrieval of microphysical properties of hydrometeors. In this paper, a dual-wavelength algorithm is described to estimate the characteristic parameters of the snow size distributions. An analysis of the computational results, made at X and Ka bands (T-39 airborne radar) and at S and...

Accurate estimates for the fall speed of natural hydrometeors are vital if their evolution in clouds is to be understood quantitatively. In this study, laboratory measurements of the terminal velocity yt for a variety of ice particle models settling in viscous fluids, along with wind-tunnel and field measurements of ice particles settling in air, have been analyzed and compared to common method...

[1] Idealized simulations of tornadogenesis in supercell storms are performed using a grid of 100 m spacing. The cold pool intensity and low-level storm dynamics are found to be very sensitive to the intercept parameters of rain and hail drop size distributions (DSD). DSDs favoring smaller (larger) hydrometeors result in stronger (weaker) cold pools due to enhanced (reduced) evaporative cooling...

Inversion algorithms for ground-based microwave radiometric retrieval of surface rain-rate, integrated cloud parameters, and slant-path attenuation are proposed and tested. The estimation methods are trained by numerical simulations of a radiative transfer model applied to microphysically-consistent precipitating cloud structures, representative of stratiform and convective rainy clouds. The di...

The impact of model microphysics on the relationships among hydrometeor profiles, latent heating, and derived satellite microwave brightness temperatures TB have been examined using a nonhydrostatic, adaptive-grid cloud model to simulate a mesoscale convective system over water. Two microphysical schemes (each employing three-ice bulk parameterizations) were tested for two different assumptions...