Published April 2019 | Version v1
Journal article

Seasonal Variations of Observed Raindrop Size Distribution in East China

  • 1. Nanjing University, Key Laboratory of Mesoscale Severe Weather of Ministry of Education and School of Atmospheric Sciences (China)

Description

Seasonal variations of rainfall microphysics in East China are investigated using data from the observations of a two-dimensional video disdrometer and a vertically pointing micro rain radar. The precipitation and rain drop size distribution (DSD) characteristics are revealed for different rain types and seasons. Summer rainfall is dominated by convective rain, while during the other seasons the contribution of stratiform rain to rainfall amount is equal to or even larger than that of convective rain. The mean mass-weighted diameter versus the generalized intercept parameter pairs of convective rain are plotted roughly around the "maritime" cluster, indicating a maritime nature of convective precipitation throughout the year in East China. The localized rainfall estimators, i.e., rainfall kinetic energy–rain rate, shape–slope, and radar reflectivity–rain rate relations are further derived. DSD variability is believed to be a major source of diversity of the aforementioned derived estimators. These newly derived relations would certainly improve the accuracy of rainfall kinetic energy estimation, DSD retrieval, and quantitative precipitation estimation in this specific region.

Abstract (Chinese)

摘 要

本研究利用二维视频雨滴谱仪和垂直指向的微降雨雷达观测资料, 分析了中国东部地区降水雨滴谱分布的季节变化特征, 揭示了不同类型降水的雨滴谱特征在不同季节均存在不同程度的差异. 夏季对流性降水对总降水的贡献约为77.5%, 而其他季节中层云降水的贡献则等于或超过对流性降水. 四个季节对流性降水的质量加权平均粒径–归一化截断参数值均位于"海洋性"对流区附近, 表明中国东部地区全年的对流性降水均具有海洋性特征. 本研究还拟合了本地化的降水估计关系, 包括降雨动能–降水率关系, 斜率–形状参数关系, 雷达反射率–降水率关系等, 有助于提高中国东部地区降雨动能估计, 雨滴谱反演和定量降水估计的精度. 分析也表明, 雨滴谱分布的变化特征是这些拟合关系出现差异的主要原因.

Additional details

Identifiers

Publishing Information

Journal Title
Advances in Atmospheric Sciences (Internet)
Journal Volume
36
Journal Issue
4
Journal Page Range
p. 346-362
ISSN
1861-9533

Optional Information

Copyright
Copyright (c) 2019 Chinese National Committee for International Association of Meteorology and Atmospheric Sciences, Institute of Atmospheric Physics, Science Press and Springer-Verlag GmbH Germany, part of Springer Nature