Open AccessMelting Layer Cloud Observed during R/V Mirai Cruise MR01-K05
Author(s) -
Kazuaki Yasunaga,
Kunio Yoneyama,
Hisayuki Kubota,
Hajime Okamoto,
Atsushi Shimizu,
Hiroshi Kumagai,
Masaki Katsumata,
Naoki Sugimoto,
Ichiro Matsui
Publication year - 2006
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/jas3779.1
Subject(s) - radiosonde , cloud base , atmospheric sciences , relative humidity , environmental science , convection , geology , meteorology , climatology , cloud computing , geography , computer science , operating system
In this study, cloud profiling radar and lidar were used to determine the frequency distribution of the base heights of cloudy layers with little (or no) falling condensate particles. The data were obtained from stationary observations conducted from Research Vessel Mirai over the tropical western Pacific (around 1.85°N, 138°E) from 9 November to 9 December 2001. The observed cloudy layers had base heights predominantly in the range of 4.5–6.5 km. Almost all cloudy layers with a base in the range of 4.5–6.5 km had thickness thinner than 500 m, and the frequency peak of the base heights of measured cloudy layers is considered to represent the common occurrence of midlevel thin clouds. Midlevel thin clouds were frequently observed even during the active phase of the Madden–Julian oscillation (MJO). Composite analysis of radiosonde-derived relative humidity and temperature lapse rate indicates that the midlevel thin cloud in the MJO active period is generated via melting within the stratiform cloud, rather than by detrainment of surface-based convection.