Open AccessGravitational separation of the stratospheric air over Syowa, Antarctica and its connection with meteorological fields
Author(s) -
Ishidoya Shigeyuki,
Sugawara Satoshi,
Inai Yoichi,
Morimoto Shinji,
Honda Hideyuki,
Ikeda Chusaku,
Hashida Gen,
Machida Toshinobu,
Tomikawa Yoshihiro,
Toyoda Sakae,
Goto Daisuke,
Aoki Shuji,
Nakazawa Takakiyo
Publication year - 2018
Publication title -
atmospheric science letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.951
H-Index - 45
ISSN - 1530-261X
DOI - 10.1002/asl.857
Subject(s) - stratosphere , atmospheric sciences , altitude (triangle) , environmental science , climatology , air mass (solar energy) , mixing ratio , physics , geology , boundary layer , geometry , mathematics , thermodynamics
To examine gravitational separation of the stratospheric air over Antarctica in austral summer, we collected air samples from altitudes of 10 to 30 km over Syowa Station (69.0°S, 39.6°E) using balloon‐borne cryogenic samplers for the period 1998–2013, and then analyzed them for δ 15 N of N 2 , δ 18 O of O 2 , δ(Ar/N 2 ) and δ 40 Ar. The normalized mass ratio “δ,” calculated using their measured values, decreases with increasing altitude, implying an upward enhancement of the gravitational separation effect. The observed stratospheric δ profiles are generally well reproduced by a two‐dimensional atmospheric model, but the model tends to underestimate the observed δ values in the middle stratosphere above 26 km. We also observe interannual variation in the δ vertical profile in the middle stratosphere. A backward trajectory analysis suggests that this variation is attributable to different horizontal mixing of the stratospheric air over Antarctica from year to year.