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the microwave radiative properties of falling snow derived from nonspherical ice particle models. part ii: initial testing using radar, radiometer and in situ observationsIn this study, two different particle models describing the structure and electromagnetic properties of snow are developed and evaluated for potential use in satellite combined radar-radiometer precipitation estimation algorithms. In the first model, snow particles are assumed to be homogeneous ice-air spheres with single-scattering properties derived from Mie theory. In the second model, snow particles are created by simulating the self-collection of pristine ice crystals into aggregate particles of different sizes, using different numbers and habits of the collected component crystals. Single-scattering properties of the resulting nonspherical snow particles are determined using the discrete dipole approximation. The size-distribution-integrated scattering properties of the spherical and nonspherical snow particles are incorporated into a dual-wavelength radar profiling algorithm that is applied to 14- and 34-GHz observations of stratiform precipitation from the ER-2 aircraft-borne High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) radar. The retrieved ice precipitation profiles are then input to a forward radiative transfer calculation in an attempt to simulate coincident radiance observations from the Conical Scanning Millimeter-Wave Imaging Radiometer (CoSMIR). Much greater consistency between the simulated and observed CoSMIR radiances is obtained using estimated profiles that are based upon the nonspherical crystal/aggregate snow particle model. Despite this greater consistency, there remain some discrepancies between the higher moments of the HIWRAP-retrieved precipitation size distributions and in situ distributions derived from microphysics probe observations obtained from Citation aircraft underflights of the ER-2. These discrepancies can only be eliminated if a subset of lower-density crystal/aggregate snow particles is assumed in the radar algorithm and in the interpretation of the in situ data.
Document ID
20170003891
Document Type
Reprint (Version printed in journal)
Authors
Olson, William S.
(Maryland Univ. Baltimore County Baltimore, MD, United States)
Tian, Lin
(Morgan State Univ. Baltimore, MD, United States)
Grecu, Mircea
(Morgan State Univ. Baltimore, MD, United States)
Kuo, Kwo-Sen
(Maryland Univ. College Park, MD, United States)
Johnson, Benjamin
(National Oceanic and Atmospheric Administration Boulder, CO, United States)
Heymsfield, Andrew J.
(National Center for Atmospheric Research Boulder, CO, United States)
Bansemer, Aaron
(National Center for Atmospheric Research Boulder, CO, United States)
Heymsfield, Gerald M.
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Wang, James R.
(Science Systems and Applications, Inc. Greenbelt, MD, United States)
Meneghini, Robert
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Date Acquired
April 25, 2017
Publication Date
March 9, 2016
Publication Information
Publication: Journal of Applied Meteorology and Climatology
Volume: 55
Issue: 3
ISSN: 1558-8424
Subject Category
Meteorology and Climatology
Report/Patent Number
GSFC-E-DAA-TN41935
Funding Number(s)
CONTRACT_GRANT: NNG11HP16A
CONTRACT_GRANT: NNX13AH73G
CONTRACT_GRANT: NNX10AI49G
CONTRACT_GRANT: NNG12HP08C
CONTRACT_GRANT: NNX17AE79A
CONTRACT_GRANT: NNX15AT34A
CONTRACT_GRANT: NNX11AR53G
CONTRACT_GRANT: NNX11AR55G
CONTRACT_GRANT: NNX13AG87G
CONTRACT_GRANT: NNX10AH67G
Distribution Limits
Public
Copyright
Other
Keywords
Ice particles; Radiances; Radiative transfer; Aircraft observations; Microwave o