Microphysical Constraints on Millimeter-Wavelength Scattering Properties of Snow Particles

• DOI: 10.1175/jamc-d-14-0137.1
• Publication Date: 2015-01-27T21:16:30Z
• Authors: Norman B. Wood; Tristan S. L’Ecuyer; Andrew J. Heymsfield; Graeme L. Stephens
• Keywords: Particle (ecology); Exponent

Abstract A Bayesian optimal estimation retrieval is used to determine probability density functions of snow microphysical parameters from ground-based observations taken during four snowfall events in southern Ontario, Canada. The retrieved variables include the power laws describing particle mass and horizontally projected area. results reveal nontrivial correlations between area that were not apparent prior studies. provide information mainly about coefficient , somewhat less exponent minimal . expected values for power-law = 0.003 28 2.25 are consistent with those several studies looked at aggregate-like particles precipitating ice aloft as maximum dimension. Differences other appear related differences dimensions define size. allows analysis relatively large volumes continuous observations, greatly enhancing sampling relative single-particle analyses. properties constrain 94-GHz (W band) radar scattering a variety shapes. Synthetic reflectivities calculated using these observed size distributions show branched, spatial produces good agreement coincident W-band reflectivities. Uncertainties synthetic reflectivities, estimated by applying simple error-propagation model, substantial dominated uncertainties