Open AccessA semiannual variation of ozone in the middle mesosphere observed with the millimeter‐wave radiometer at Tsukuba, Japan
Author(s) -
Nagahama Tomoo,
Nakane Hideaki,
Fujinuma Yasumi,
Ogawa Hideo,
Mizuno Akira,
Fukui Yasuo
Publication year - 2003
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2003jd003724
Subject(s) - radiometer , altitude (triangle) , atmospheric sciences , ozone , environmental science , mixing ratio , variation (astronomy) , mesosphere , amplitude , stratosphere , climatology , geology , meteorology , remote sensing , physics , astronomy , optics , geometry , mathematics
Continuous observations of the vertical ozone profiles between 38 and 76 km in altitude have been made with the millimeter‐wave radiometer at Tsukuba, Japan (36.1°N, 140.1°E) since October 1996. We analyzed temporal variations of ozone at various altitudes and first identified clearly the features of a semiannual variation between 56 and 68 km. The ozone mixing ratio in this region peaks in January and July, and the amplitude of the semiannual variation at 60 km was estimated to be 13% of the annual average, which is about half the value of 28% observed at 76 km. The phase of the semiannual variation from 56 to 76 km inverts suddenly at around 68 km, suggesting that these semiannual variations of ozone are not induced by the propagation of any kind of wave but are caused by different mechanisms in the regions above and below 68 km.