Editorial Type:
Article
Article Type:
Research Article

Modeling Raindrop Size Distribution and Z(R) Relations in the Western Mediterranean Area

Carlos Cerro Department of Astronomy and Meteorology, University of Barcelona, Barcelona, Spain

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Bernat Codina Department of Astronomy and Meteorology, University of Barcelona, Barcelona, Spain

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Joan Bech Department of Astronomy and Meteorology, University of Barcelona, Barcelona, Spain

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Jeroni Lorente Department of Astronomy and Meteorology, University of Barcelona, Barcelona, Spain

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Print Publication:
01 Nov 1997
DOI:
https://doi.org/10.1175/1520-0450(1997)036<1470:MRSDAZ>2.0.CO;2
Page(s):
1470–1479
Restricted access

Abstract

This study shows the results of the modeling of drop size distributions (DSD) observed during a 2-yr study in Barcelona. Thirty-second individual sample collections of drop sizes and velocities were measured with an optical disdrometer and grouped into different classes according to their rain rate. Using the moments method, the entire experimental dataset was fitted to three standard distribution functions: exponential, gamma, and lognormal. Relationships were found between rain rate R and other moments of the DSD, such as optical attenuation Σ, liquid water content W, and reflectivity Z. Although gamma distribution generally reproduced experimental measurements more accurately, the Z(R) relationship, which is particularly relevant in radar meteorology, yielded the best results when calculated from fitted exponential distribution.

Corresponding author address: Dr. Jeroni Lorente, Department of Astronomy and Meteorology, University of Barcelona, Auguda Diagonal, 647 E-08028 Barcelona, Spain.

Abstract

This study shows the results of the modeling of drop size distributions (DSD) observed during a 2-yr study in Barcelona. Thirty-second individual sample collections of drop sizes and velocities were measured with an optical disdrometer and grouped into different classes according to their rain rate. Using the moments method, the entire experimental dataset was fitted to three standard distribution functions: exponential, gamma, and lognormal. Relationships were found between rain rate R and other moments of the DSD, such as optical attenuation Σ, liquid water content W, and reflectivity Z. Although gamma distribution generally reproduced experimental measurements more accurately, the Z(R) relationship, which is particularly relevant in radar meteorology, yielded the best results when calculated from fitted exponential distribution.

Corresponding author address: Dr. Jeroni Lorente, Department of Astronomy and Meteorology, University of Barcelona, Auguda Diagonal, 647 E-08028 Barcelona, Spain.

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Journal of Applied Meteorology and Climatology

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