Open AccessA Study of Cirrus Ice Particle Size Distribution Using TC4 Observations
Author(s) -
Lin Tian,
Gerald M. Heymsfield,
Lihua Li,
Andrew J. Heymsfield,
Aaron Bansemer,
Cynthia H. Twohy,
R. C. Srivastava
Publication year - 2010
Publication title -
journal of the atmospheric sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.853
H-Index - 173
eISSN - 1520-0469
pISSN - 0022-4928
DOI - 10.1175/2009jas3114.1
Subject(s) - log normal distribution , cirrus , exponential function , spectral line , gamma distribution , physics , probability density function , cumulative distribution function , particle size distribution , standard deviation , exponential distribution , particle (ecology) , distribution function , statistical physics , computational physics , atmospheric sciences , particle size , statistics , mathematics , geology , thermodynamics , mathematical analysis , quantum mechanics , paleontology , oceanography
An analysis of two days of in situ observations of ice particle size spectra, in convectively generated cirrus, obtained during NASA’s Tropical Composition, Cloud, and Climate Coupling (TC4) mission is presented. The observed spectra are examined for their fit to the exponential, gamma, and lognormal function distributions. Characteristic particle size and concentration density scales are determined using two (for the exponential) or three (for the gamma and lognormal functions) moments of the spectra. It is shown that transformed exponential, gamma, and lognormal distributions should collapse onto standard curves. An examination of the transformed spectra, and of deviations of the transformed spectra from the standard curves, shows that the lognormal function provides a better fit to the observed spectra.