• Beard, K. V., and C. Chuang, 1987: A new model for the equilibrium shape of raindrops. J. Atmos. Sci.,44, 1509–1524.

    • Crossref
    • Export Citation
  • Chandrasekar, V., W. A. Cooper, and V. N. Bringi, 1988: Axis ratios and oscillations of raindrops. J. Atmos. Sci.,45, 1323–1333.

    • Crossref
    • Export Citation
  • ——, G. R. Gray, and I. J. Caylor, 1993: Auxiliary signal processing system for a multiparameter radar. J. Atmos. Oceanic Technol.,10, 428–431.

  • Gorgucci, E., and G. Scarchilli, 1997: Intercomparison of multiparameter radar algorithms for estimating rainfall rate. Preprints, 28th Conf. on Radar Meteorology, Austin, TX, Amer. Meteor. Soc., 55–56.

  • Green, A. W., 1975: An approximation for the shapes of large raindrops. J. Appl. Meteor.,14, 1578–1583.

    • Crossref
    • Export Citation
  • Hubbert, J., V. Chandrasekar, and V. N. Bringi, 1993: Processing and interpretation of coherent dual-polarized radar measurements. J. Atmos. Oceanic Technol.,10, 155–164.

  • Liu, L., V. N. Bringi, V. Chandrasekar, E. A. Mueller, and A. Mudukutore, 1994: Analysis of the copolar correlation coefficient between horizontal and vertical polarizations. J. Atmos. Oceanic Technol.,11, 950–963.

    • Crossref
    • Export Citation
  • Mueller, E. A., 1984: Calculation procedures for differential propagation phase shift. Preprints, 22nd Conf. on Radar Meteorology, Zurich, Switzerland, Amer. Meteor. Soc., 397–399.

  • Pruppacher, H. R., and R. L. Pitter, 1971: A semi-empirical determination of the shape of cloud and raindrops. J. Atmos. Sci.,28, 86–94.

    • Crossref
    • Export Citation
  • Sachidananda, M., and D. S. Zrnic, 1987: Rain rate estimates from differential polarization measurements. J. Atmos. Oceanic Technol.,4, 588–598.

    • Crossref
    • Export Citation
  • Scarchilli G., E. Gorgucci, V. Chandrasekar, and A. Dobaie, 1996: Self-consistency of polarization diversity measurement of rainfall. IEEE Trans. Geosci. Remote Sens.,34, 22–26.

    • Crossref
    • Export Citation
  • Seliga, T. A., and V. N. Bringi, 1976: Potential use of the radar reflectivity at orthogonal polarizations for measuring precipitation. J. Appl. Meteor.,15, 69–76.

    • Crossref
    • Export Citation
  • ——, and ——, 1978: Differential reflectivity and differential phase shift: Application in radar meteorology. Radio Sci.,13, 271–275.

    • Crossref
    • Export Citation
  • Ulbrich, C. W., 1983: Natural variations in the analytical form of raindrop size distributions. J. Climate Appl. Meteor.,22, 1764–1775.

    • Crossref
    • Export Citation
  • Zrnic, D. S., and A. V. Ryzhkov, 1996: Advantages of rain measurements using specific differential phase. J. Atmos. Oceanic Technol.,13, 454–464.

    • Crossref
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 231 84 5
PDF Downloads 100 69 12

Specific Differential Phase Estimation in the Presence of Nonuniform Rainfall Medium along the Path

View More View Less
  • 1 Istituto di Fisica dell’Atmosfera, Rome, Italy
  • | 2 Colorado State University, Fort Collins, Colorado
Restricted access

Abstract

Specific differential propagation phase (KDP) is estimated as the slope of the differential propagation phase (ΦDP). The estimate of specific differential propagation phase is typically obtained over a path to minimize measurement error. It is shown that the estimate of specific differential phase over a nonuniform rainfall path is biased, and the bias increases with increased reflectivity variation along the path. It is also shown that the bias can be both positive and negative depending on the nature of nonuniformity in the propagation path. Three models for nonuniform reflectivity variation along the precipitation path are studied. A simple algorithm is presented to correct the bias in the estimation of KDP due to nonuniform rainfall paths. Multiparameter radar data collected over central Florida are analyzed and compared to the theoretical results developed in this paper.

Corresponding author address: Dr. Eugenio Gorgucci, Istituto di Fisica dell’Atmosfera, Via del Fosso del Cavaliere, 100, Area di Ricerca Roma-Tor Vergata, 00133 Rome, Italy.

Email: gorgucci@radar.ifa.rm.cnr.it

Abstract

Specific differential propagation phase (KDP) is estimated as the slope of the differential propagation phase (ΦDP). The estimate of specific differential propagation phase is typically obtained over a path to minimize measurement error. It is shown that the estimate of specific differential phase over a nonuniform rainfall path is biased, and the bias increases with increased reflectivity variation along the path. It is also shown that the bias can be both positive and negative depending on the nature of nonuniformity in the propagation path. Three models for nonuniform reflectivity variation along the precipitation path are studied. A simple algorithm is presented to correct the bias in the estimation of KDP due to nonuniform rainfall paths. Multiparameter radar data collected over central Florida are analyzed and compared to the theoretical results developed in this paper.

Corresponding author address: Dr. Eugenio Gorgucci, Istituto di Fisica dell’Atmosfera, Via del Fosso del Cavaliere, 100, Area di Ricerca Roma-Tor Vergata, 00133 Rome, Italy.

Email: gorgucci@radar.ifa.rm.cnr.it

Save