WAVE BREAKING SIGNATURES IN NOCTILUCENT CLOUDS

被引：97

作者：

FRITTS, DC ^{[1
]}

ISLER, JR ^{[1
]}

THOMAS, GE ^{[1
]}

ANDREASSEN, O ^{[1
]}

机构：

[1] NORWEGIAN DEF RES ESTAB,N-2007 KJELLER,NORWAY

来源：

GEOPHYSICAL RESEARCH LETTERS | 1993年 / 20卷 / 19期

关键词：

D O I：

10.1029/93GL01982

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

Results of a recent modeling study of gravity wave breaking in three dimensions by Andreassen et al. and Fritts et al. showed wave saturation to occur via a three-dimensional instability oriented normal to the direction of wave propagation. The instability was found to occur at horizontal scales comparable to the depth of unstable regions within the wave field and to lead to substantial vertical displacements and tilting of isentropic surfaces. Because of strong similarities between the wave and instability structures in the simulation and the structure observed in noctilucent cloud layers near the summer mesopause, we have used these model results to compute the advective effects on cloud visibility and structure for a range of viewing angles and cloud layer widths. Our results show the gravity wave breaking signature to provide a plausible explanation of the observed structures and suggest that noctilucent cloud structures may be used in turn to infer qualitative properties of gravity wave scales, energy and momentum transports, and turbulence scales near the summer mesopause.

引用

页码：2039 / 2042

页数：4

共 14 条

[1]

ANDREASSEN O, 1993, UNPUB J GEOPHYS RES

[2]

[Anonymous], 1989, NOCTILUCENT CLOUDS

[3] CONVECTIVE AND DYNAMICAL INSTABILITIES DUE TO GRAVITY-WAVE MOTIONS IN THE LOWER AND MIDDLE ATMOSPHERE - THEORY AND OBSERVATIONS [J].