Open AccessThe Droplike Nature of Rain and Its Invariant Statistical Properties
Author(s) -
Massimiliano Ignaccolo,
Carlo De Michele,
Simone Bianco
Publication year - 2009
Publication title -
journal of hydrometeorology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.733
H-Index - 123
eISSN - 1525-755X
pISSN - 1525-7541
DOI - 10.1175/2008jhm975.1
Subject(s) - drop (telecommunication) , scaling , invariant (physics) , mathematics , probability density function , statistical physics , power law , scale invariance , standard deviation , thermodynamics , physics , mechanics , statistics , mathematical physics , geometry , computer science , telecommunications
This study looks for statistically invariant properties of the sequences of inter-drop time intervals and drop diameters. The authors provide evidence that these invariant properties have the following characteristics: 1) large inter-drop time intervals (≳10 s) separate drops of small diameter (≲0.6 mm); 2) the rainfall phenomenon has two phases: a quiescent phase, whose contribution to the total cumulated flux is virtually null, and an active, nonquiescent, phase that is responsible for the bulk of the precipitated volume; 3) the probability density function of inter-drop time intervals has a power-law-scaling regime in the range of ∼1 min and ∼3 h); and 4) once the moving average and moving standard deviation are removed from the sequence of drop diameters, an invariant shape emerges for the probability density function of drop diameters during active phases.