耗散大气中风场对内重力波传播的影响

摘要

By using ray-tracing method, features of propagation of internal gravitywaves under the influence of winds are calculated. The results indicatethat the cut-off region of gravity waves seems not affected by winds, whilereflecting and propagating regions are significantly influenced. Thereflecting region reduces when gravity waves propagate downwind and expands whenagainst wind. In propagating region, propitions winds shorten theattenuation distance of slow gravity waves and reduce their propagatingheight, while converse winds lengthen the attenuation distance ofslow gravity waves and rise the attenuation height. Further analysis showsthat the diversity of gravity wave propagation features is caused by the effectof winds on the processes of gravity wave attenuation and reflection.%使用考虑大气耗散的射线跟踪算法, 计算了风场作用下重力波的传播情况. 结果表明, 风场对快速重力波分量影响较小,但对反射和传播区域的慢速波的影响较大,表现在顺风时使反射区范围缩小,逆风时使反射区范围扩大.在传播区,顺风场使慢速波分量的传播距离变小,传播高度降低,而逆风则使慢速重力波分量的传播距离明显增大,传播高度上升.分析表明,重力波传播的丰富多样性是由风场对波的衰减和反射等滤波作用引起的.