The universal scaling characteristics of tropical oceanic rain clusters
Cheung, K. K. W.
Chew, Lock Yue
Date of Issue2017
School of Physical and Mathematical Sciences
Using multiyear satellite rainfall estimates, the distributions of the area, and the total rain rate of rain clusters over the equatorial Indian, Pacific, and Atlantic Oceans was found to exhibit a power law math formula, in which S represents either the cluster area or the cluster total rain rate and fS(s) denotes the probability density function of finding an event of size s. The scaling exponents ζS were estimated to be 1.66 ± 0.06 and 1.48 ± 0.13 for the cluster area and cluster total rain rate, respectively. The two exponents were further found to be related via the expected total rain rate given a cluster area. These results suggest that convection over the tropical oceans is organized into rain clusters with universal scaling properties. They are also related through a simple scaling relation consistent with classical self-organized critical phenomena. The results from this study suggest that mesoscale rain clusters tend to grow by increasing in size and intensity, while larger clusters tend to grow by self-organizing without intensification.
Tropical rain clusters
Journal of Geophysical Research: Atmospheres
© 2017 American Geophysical Union (AGU). This paper was published in Journal of Geophysical Research: Atmospheres and is made available as an electronic reprint (preprint) with permission of American Geophysical Union (AGU). The published version is available at: [http://dx.doi.org/10.1002/2016JD025921]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.