Rain relations inferred from microphysical data in TOGA COARE and their use to test a rain-profiling method from radar measurements at Ku-band

Abstract The first part of this paper is dedicated to establishing relations among rain-integrated parameters representative of west Pacific precipitation. This is achieved by using airborne microphysical data gathered within a rain event on 6 February 1993 during the Tropical Ocean and Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE). The relations between the rain rate R, the reflectivity factor Z, and the attenuation coefficient K are calculated for moderate to heavy precipitation at 13.8 GHz. They give twice as much attenuation for a given Z than the relations obtained for an exponential distribution with N0 = 8 × 106 m−4. This effect is related to the large number of small size particles observed in TOGA COARE convective systems. In the second part of the paper, these relations are used to check the reliability of a rain-profiling method applied to ARMAR (airborne radar-mapping radar) observations at 13.8 GHz in the same rain event. This method provides a bulk correction fa...

[1]  Robert Meneghini,et al.  Determination of Rain Rate from a Spaceborne Radar Using Measurements of Total Attenuation , 1983, IEEE Transactions on Geoscience and Remote Sensing.

[2]  J. Hallett,et al.  Observations of the Distribution of Ice in Hurricanes , 1986 .

[3]  Richard K. Moore,et al.  Preliminary study of rain effects on radar scattering from water surfaces , 1979 .

[4]  J. Marshall,et al.  THE DISTRIBUTION OF RAINDROPS WITH SIZE , 1948 .

[5]  P. Amayenc,et al.  A Class of Single- and Dual-Frequency Algorithms for Rain-Rate Profiling from a Spaceborne Radar. Part II: Tests from Airborne Radar Measurements , 1996 .

[6]  Walter Hitschfeld,et al.  ERRORS INHERENT IN THE RADAR MEASUREMENT OF RAINFALL AT ATTENUATING WAVELENGTHS , 1954 .

[7]  D. Short,et al.  Evidence from Tropical Raindrop Spectra of the Origin of Rain from Stratiform versus Convective Clouds , 1996 .

[8]  R. Gunn,et al.  THE TERMINAL VELOCITY OF FALL FOR WATER DROPLETS IN STAGNANT AIR , 1949 .

[9]  C. Ulbrich.  Natural Variations in the Analytical Form of the Raindrop Size Distribution , 1983 .

[10]  Robert Meneghini,et al.  Experimental Tests of Methods for the Measurement of Rainfall Rate Using an Airborne Dual-Wavelength Radar , 1989 .

[11]  Carlton W. Ulbrich,et al.  The rain parameter diagram: Methods and applications , 1978 .

[12]  David Atlas,et al.  Footprints of storms on the sea: A view from spaceborne synthetic aperture radar , 1994 .

[13]  Fuk K. Li,et al.  ARMAR: An airborne rain-mapping radar , 1994 .

[14]  Robert Meneghini,et al.  Intercomparison of Single-Frequency Methods for Retrieving a Vertical Rain Profile from Airborne or Spaceborne Radar Data , 1994 .

[15]  Mongi Marzoug,et al.  A Class of Single- and Dual-Frequency Algorithms for Rain-Rate Profiling from a Spaceborne Radar. Pad I: Principle and Tests from Numerical Simulations , 1994 .

[16]  Robert Meneghini,et al.  Range profiling of the rain rate by an airborne weather radar , 1990 .

[17]  A. Spilhaus.  RAINDROP SIZE, SHAPE AND FALLING SPEED , 1948 .

[18]  P. Webster,et al.  TOGA COARE: The Coupled Ocean-Atmosphere Response Experiment. , 1992 .

[19]  K. Beard.  Terminal Velocity and Shape of Cloud and Precipitation Drops Aloft , 1976 .

[20]  Robert F. Adler,et al.  A Proposed Tropical Rainfall Measuring Mission (TRMM) Satellite , 1988 .

[21]  Hiroshi Kumagai,et al.  A Study of Rain Estimation Methods from Space Using Dual-Wavelength Radar Measurements at Near-Nadir Incidence over Ocean , 1992 .

[22]  P. Ray,et al.  Broadband complex refractive indices of ice and water. , 1972, Applied optics.

[23]  Kenji Nakamura,et al.  Dual-parameter radar rainfall measurement from space: a test result from an aircraft experiment , 1991, IEEE Trans. Geosci. Remote. Sens..

[24]  P. Waterman.  Matrix formulation of electromagnetic scattering , 1965 .

[25]  Louis J. Battan,et al.  Radar Observation of the Atmosphere , 1973 .

[26]  Toshiaki Kozu,et al.  Rainfall Parameter Estimation from Dual-Radar Measurements Combining Reflectivity Profile and Path-integrated Attenuation , 1991 .