Instability of Frontal Waves and Upper Level Frontogenesis

Drs。Mechoso和Arakawa将继续他们在前线的两个主要研究重点。首先，他们正在研究导致锋面形成和锋面上不稳定次波产生的过程，特别是在对流层中高层。其次，他们正在开发适合研究锋面现象的新的数值方法。研究人员先前的工作现在导致了几个主题的具体考虑：(1)使用相对压力（.）作为垂直坐标的模型和使用势温（>）的模型的比较优缺点；(2)锋面小尺度扰动的起源与演变；(3)绝热过程在锋生过程中的作用；(4)发展了垂直坐标逐渐由。在地面到b>在上层。在先前的资助下，主要研究人员在开发能够解决锋面形成过程的大型模型方面取得了相当大的进展。他们还成功地解决了有关这些进程的一些基本问题。他们的研究最终将有助于改进业务天气预报模式。

Drs. Mechoso and Arakawa will continue their two primary research thrusts on fronts. First, they are investigating processes which lead to frontal formation and the generation of unstable secondary waves on fronts, particularly in the middle and upper troposphere. Second, they are developing new numerical methods suitable for the study of frontal phenomena. Previous work by the investigators now leads to the specific consideration of several topics: (1) the comparative advantages and disadvantages of models which use relative pressure (.) as the vertical coordinate and those which use potential temperature (>); (2) the origin and evolution of small-scale disturbances on fronts; (3) the role of diabatic processes in frontogenesis; and (4) the development of primitive-equation models with a vertical coordinate that gradually changes from . at the surface to > at upper levels. Under their previous grant, the principal investigators made considerable progress in their work on the development of large scale models capable of resolving frontogenetic processes. They have also succeeded in addressing some of the fundamental questions about these processes. Their research ultimately will contribute to the improvement of operational weather forecast models.