Dynamic Meteorology

Keywords: Meteorology, atmospheric equilibrium, meteorological forecast
Prerequisites: Bases on fluid mechanics are useful

The Earth’s atmosphere is a natural laboratory, in which a wide variety of physical processes takes place. The purpose of this course is to show how basic physical principles can help us model, interpret and predict some of these processes. The first part of this course will help to understand the approaches to weather forecasting based on basic concepts of dynamical meteorology. For this purpose, we will first recall the dynamical quantities essential in meteorology and in the major atmospheric equilibria. The various types of atmospheric weather phenomena and their main characteristics will then be described. Meteorological maps will be examined to illustrate the different concepts and to show how a forecast can be conducted.

The second part will deal with the general circulation of the troposphere based on observations and conceptual models. First, we will consider the mean zonal circulation, the Hadley and Ferrel cells by introducing different notions in this framework, such as the Eliassen-Palm fluxes. Then, the three-dimensional aspects of the circulation at the middle latitudes will be studied, such as the stationary Rossby waves generated by the orography, or the synoptic transient Rossby waves generated by thermal contrasts. The study of these various waves will be based on ray theory  as well as on energy budgets like  the Lorenz cycle.