著者
YAMADA Hiroyuki ITO Kosuke TSUBOKI Kazuhisa SHINODA Taro OHIGASHI Tadayasu YAMAGUCHI Munehiko NAKAZAWA Tetsuo NAGAHAMA Norio SHIMIZU Kensaku
出版者
Meteorological Society of Japan
雑誌
気象集誌. 第2輯 (ISSN:00261165)
巻号頁・発行日
pp.2021-063, (Released:2021-07-01)
被引用文献数
10

Upper-tropospheric aircraft reconnaissance was carried out for Typhoon Lan (2017) using a civil jet with a newly developed dropsonde system. This was the first case of a Japanese research group observing the inner core of an intense typhoon using dropsondes. This paper describes the warm-core structure in the eye and the associated thermodynamic and kinematic features of the eyewall. During two days of reconnaissance, this typhoon preserved its peak intensity in an environment with a strengthening vertical shear. Dropsondes captured a double warm-core structure with a higher perturbation temperature in the middle and upper troposphere, which persisted between the two flight missions. The two warm cores show a difference in the equivalent potential temperature (θe) of more than 10 K, suggesting different air origins. Saturation point analysis suggest that air observed in the upper warm core was entrained from the eyewall. The eyewall updraft in the left-of-shear semicircle had a two-layer structure with a higher θe and lower absolute angular momentum on the inner side of the updraft core. Analyses of the saturation point and parcel method suggest that the warmer air with a θe exceeding 370 K on the inner side of the updrafts originated from the eye boundary layer and was eventually transported into the upper warm core. These results led us to hypothesize that the vertical transport of high-θe air from the eye boundary layer contributed to the continuous eye warming in the upper troposphere against the negative effect of a strengthening environmental wind shear on the storm intensity. This study demonstrates the significance of eyewall-penetrating upper-tropospheric reconnaissance for monitoring the warm-core structure in the present situation where accurate measurements of both humidity and temperature for calculating θe can only be made with dropsonde-type expendables.
著者
Jauhiainen Hannu Fujiwara Masatomo Philipona Rolf Dirksen Ruud Hurst Dale F. Kivi Rigel Vömel Holger Demoz Belay Kizu Nobuhiko Oakley Tim Shimizu Kensaku Maturilli Marion Leblanc Thierry Madonna Fabio Querel Richard
出版者
GRUAN Lead Centre
雑誌
GRUAN Technical document
巻号頁・発行日
vol.7, pp.1-44, 2019

Various rigging configurations for multiple-payload radiosonde soundings have been used when characterizing different radiosonde instruments, when changing the radiosonde model at operational radiosonde sites or when flying specially developed scientific sensors together with a radiosonde. This paper describes such rigging configurations currently in use at sites of the Global Climate Observing System (GCOS) Reference Upper Air Network (GRUAN) or having been used during recent international radiosonde intercomparison campaigns. The advantages and potential issues for each configuration are discussed in detail. Though it is difficult to provide one single recommendation for all conditions, the paper aims at providing all the key information relevant to the multiple-payload configurations towards the future determination of the best-practice guidance for GRUAN and other sites.