Titan's atmosphere: temperature and dynamics
Titan's atmosphere: temperature and dynamics
复制标题
泰坦的大气层：温度和动力学
作者：
F. Flasar;R. Samuelson;B. Conrath
在土卫六低层大气中，红外亮度温度呈现出3 K左右的对比度.由于辐射时间常数大，因此没有季节变化。在平流层上部，纬向对比度为100 K，与100 m s−1的旋向纬向风相一致，辐射时间常数很短，这意味着温度和风场的季节变化很大。纵向热结构的缺乏意味着纬向对称流动影响热的纬向输送。一个简单的模型在对流层下部产生的纬向速度为<$0.04 cm s−1，垂直涡动粘度为<$103 cm 2 s−1，在平流层上部产生的纬向速度为<$5 cm s−1。
In the lower atmosphere of Titan IR brightness temperatures exhibit meridional contrast \[lsims]3 K. Seasonal variations are absent because of the large radiative time constant. In the upper stratosphere meridional contrasts are ∼20 K, consistent with 100 m s−1 cyclostrophic zonal winds, and the radiative time constant is short, implying a large seasonal variation in the temperature and wind field. The absence of longitudinal thermal structure implies that zonally symmetric flows effect the meridional transport of heat. A simple model yields meridional velocities ∼0.04 cm s−1 and vertical eddy viscosities ∼103 cm2 s−1 in the lower troposphere, and meridional velocities ∼5 cm s−1 in the upper stratosphere.