Control of the homopause level
Control of the homopause level
复制标题
同质绝经水平的控制
DOI：
10.1016/0019-1035(82)90128-2
复制
发表时间：
1982
期刊：
影响因子：
3.2
通讯作者：
C. Leovy
中科院分区：
文献类型：
--
作者：
C. Leovy
本文评述了重力内波破碎是高层大气湍流产生和控制同层顶数密度的因素的假说。来自火星和地球的现有数据支持最初由Lindzen提出的假设，即打破热潮汐是必要的湍流。最低阶、赤道捕获、向西传播的昼夜潮汐模式是地球上的主要原因，而较低阶的向西传播的半日潮汐模式是火星上的主要原因。负责模式的频率和垂直波数决定了涡流扩散系数;能量密度只间接涉及确定哪些模式可以打破。潮汐加热和速度振幅之间的一般尺度关系可以用来评估潮汐模式的破坏潜力，并在这里作为论证火星同层顶的数量密度可能在大部分地质时期都是稳定的基础。在金星和泰坦的情况下，这种方法会出现困难，因为它们有特殊的纬向风。对于木星和土星，由非潮汐机制产生的内部重力波可能控制着同层顶。
This paper reviews the hypothesis that internal gravity wave breaking in the factor responsible for upper atmosphere turbulence generation and control of the number density at the homopause level. Available data from Mars and Earth support the hypothesis, originally introduced by Lindzen, that breaking thermal tides are responsible for the necessary turbulence. The lowest-order, equatorially trapped, westward-propagating diurnal tidal mode is the primary cause on the Earth, and lower-order westward-propagating semidiurnal modes are the primary cause on Mars. The frequencies and vertical wavenumbers of the responsible modes determine the eddy diffusion coefficients; energy density is only indirectly involved by determining which modes can break. A general scale relationship between tidal heating and velocity amplitude can be used to assess the breaking potential of tidal modes, and is used here as the basis for arguing that the number density at the Martian homopause is likely to have been stable over much of geologic time. Difficulties with this approach arise in the cases of Venus and Titan because of their peculiar zonal winds. For Jupiter and Saturn, internal gravity waves generated by nontidal mechanisms probably control the homopause.
影响因子：
25.2
作者：
J. Forbes;H. Garrett
通讯作者：
J. Forbes;H. Garrett