General circulation of the atmosphere

The general circulation of the atmosphere consists of the large-scale atmospheric flow, including its time-averaged structure and its statistical properties. The atmospheric circulation transports heat, moisture and momentum, determining regional climate properties and affecting the global distribution of energy. This chapter describes the main elements of the atmospheric circulation, and reviews the physical principles controlling the observed circulation properties. The chapter focuses on the climatological zonal-mean flow in the troposphere, which consists of the overturning meridional circulation cells and the jet streams, and on the role of deviations from the averaged flow, called eddies. The dynamics of eddies and their influence on the climatological zonal-mean flow are discussed.